Food Processing PDF

Introduction to Food Processing Food processing Dr. Mohammed Alsebaeai Assistance Professor (Ph. D) in Food science Lebanese International University Food Science It is a distinct field involving the application of basic sciences such as chemistry and physics, ar...

Introduction to Food Processing Food processing Dr. Mohammed Alsebaeai Assistance Professor (Ph. D) in Food science Lebanese International University Food Science It is a distinct field involving the application of basic sciences such as chemistry and physics, arts, agronomics and microbiology Food preservation Food preservation is the process of treating and handling food in such a way as to stop or greatly slow down its spoilage and to prevent food borne illness while maintaining the food item’s nutritional value, texture and flavor. Type of food processing PRIMARY PROCESSING Primary processing is the conversion of raw materials to food commodities. Milling is an example of primary processing. SECONDARY PROCESSING Secondary processing is the conversion of ingredients into edible products - this involves combining foods in a particular way to change properties. Baking cakes is an example of secondary processing. Processing and Preservation Technologies Used in the Food industry: Heating Drying Irradiation Concentration Freezing Chemical preservation Chilling Fermentation A combination of those technologies Product development Product development is the process of making new or modified food products. The process of product development involves a complex series of stages, requiring the combined talents of many specialists to make it successful. The aim of product development is for a company to increase sales and remain competitive. Reason for food processing 1. Prevent, reduce, eliminate infestation of food with microbes, insects or other vermin 2. Prevent microbial growth or toxin production by microbes, or reduce these risks to acceptable levels 3. Stop or slow deteriorative chemical or biochemical reactions 4. Maintain and/or improve nutritional properties of food 5. Increase storage stability or shelf life of food 6. Make food more palatable and attractive 7. Make foods for special groups of people Stages of product development 1. Develop ideas for a new product 2. Test ideas on a small scale 3. Sensory evaluation 4. Modify product 5. Pilot plant 6. Sensory evaluation 7. Perform consumer testing 8. Finalize product specification 9. Produce product on a large scale Yeast leaven bread Food processing Dr. Mohammed Alsebaeai  Food processing Techniques used to slow deterioration and allow people to enjoy foods in a variety of forms around the year and around the globe. Food processing turns raw agricultural product into attractive and consumable food.  Importance of food processing to human health 1. Increases variety 2. Increases convenience 3. Improves quality of food  The most common five food processing methods Fermentation - Production of CO2 through anaerobic respiration, also produces lactic acid alcohol in the process. Canning - Sterilize food by getting it to a temperature of 212-250 F, then putting it into airtight containers. Dehydration - Lowers moisture content to inhibit growth of microorganisms. Irradiation - Uses gamma rays to kill insects, bacteria, fungi, etc. in food products. Blanching - Briefly scald food to inactivate enzymes that cause undesirable changes.  Yeast leavened bread The essential ingredients in yeast-leavened bread are: 1) wheat flour 2) water 3) yeast 4) salt Most bread produced in different countries incorporates small amounts of additional ingredients.  Yeast leavened bread White-pan bread It is most commonly produced bread in many countries These nonessential ingredients allow the baker to: compensate for flour deficiencies They may also add color or desirable flavor attributes that improve consumer acceptability. 1. Sugar, shortening (fat), 2. Milk or milk products 3. Yeast foods 4. Surfactants 5. Enzymes, 6. Mold inhibitors WHITE-PAN BREAD WHITE-PAN BREAD VERSUS VARIETY BREADS White-pan breads are identified as Any bread, other than a variety bread. Variety bread formulations often include meals or grits with or without wheat flour. Whole wheat, rye, oats, barley, and millet are typical grain choices  The flavor and the crust and crumb characteristics of variety breads differ to varying degrees from white-pan breads. Production procedures also vary, with the extent to which variety bread production is similar to that of white- pan bread depending on the specific product being made. VARIETY BREAD WHITE-PAN BREAD QUALITY CRITERIA 1. Loaf volume, expressed as cubic centimeters/unit of weight, is the major criterion used to assess bread quality. 2. Loaf shape, height, and length and the relative proportions of loaf height and length are part of this quality assessment. 3. In white-pan breads, the loaf should have a rounded top without sharp corners or protruding sides and ends. 4. Crumb color should be a creamy white without streaks or spots. 5. Flavor, which includes both taste and aroma, should be pleasing and characteristic of the grain in the formulation; it is assessed subjectively.  Raw materials preparation Wheat flour comprises 55–60% of white-pan bread. Wheat flour characteristics are determined by : 1. The wheat(s) selected 2. The milling process 3. The treatments applied post milling. A. WHEAT SELECTION Selection among available wheats is based on the intended end use. Three commercially significant wheat species are important: 1. Triticum compactum (club wheat), which is used in cake and pastry flours 2. T. durum, which is used in pasta production 3. T. aestivum, is the preferred wheat species wherever yeast leavened breads and related dough-based products are produced.  Hard versus soft refers to 1. kernel characteristics 2. how tightly the starch granules are packed in the protein matrix  Relative hardness of the wheat kernels influences milling characteristics. Hard wheats exhibit greater resistance to grinding than soft wheats during the milling process. Hard wheats are higher than soft wheats in protein.  Red and white refers to kernel color, which is determined by whether or not there is a red pigment in the outer layers of the wheat kernel. Spring and winter refers to growth habit. The tests conducted on wheat prior to milling 1. Moisture 2. Bulk density 3. Protein 4. Sprout damage The results of these tests help the miller determine the blend characteristics. C. MILLING The wheat selected is milled with a dry process. When wheat arrives at the mill, it contains foreign material that will affect the 1. Appearance, 2. Functionality, 3. Mill operation. Cleaning occurs either before or after the blending process. Cleaning is usually a dry process involving several steps. 1. Magnets are used to remove ferrous materials; 2. a stoner removes foreign materials such as small stones and mud balls that differ in specific gravity from wheat. 3. A milling separator screens impurities that are larger and smaller than the wheat kernels, such as corn, mustard seeds, or soybeans. 4. Wheat kernels also undergo a dry scour. In this step, the wheat kernels are impelled against a screen to abrade the surface. This removes impurities in the crease, which are otherwise very difficult to eliminate.  The controlled addition of moisture for up to 36 hours, called tempering or conditioning. At a moisture content of about 15–16%, maximum milling efficiency and optimum performance of the resulting flour in the final product is achieved.  These corrugated break rollers rotate at different speeds in opposite directions, breaking the wheat kernel into coarse particles and thereby exposing the endosperm. The sheared and crushed kernels pass through a series of sieves that separates the material into three general size categories, 1. The coarsest fragments are sent through the next break, 2. The medium-sized particles are primarily endosperm and are known as middlings, 3. The finest particles are break flour.  After the fifth or sixth break, the remaining coarse particles are primarily bran. Most of the germ is removed by the third break. Finally, the medium-sized particles (middlings) from all the breaks are passed through a series of smooth reduction rolls. After each passage, in which the middlings are reduced in size and the adhering bran is loosened, the particles are sieved.  When all of the millstreams are combined, the resultant product is known as straight flour. One hundred pounds of cleaned wheat will yield about 72 pounds of straight flour and 28 pounds of byproducts; thus, there is a 72% extraction rate.  The by-products, also known as shorts, are 1. Bran 2. Germ 3. Some endosperm. The flour produced by milling is composed 1. Endosperm 2. Starch 3. Protein.  Separation of protein and starch Because the sizes of the protein and starch particles are very similar, sieving does not separate these fractions. Centrifugal force applied to the suspended particles yields two flour fractions that differ in starch and protein content. POSTMILLING TREATMENTS Postmilling treatment includes the incorporation of maturing and bleaching agents and enrichment. Oxidants such as benzoyl peroxide are added to bleach (whiten) the yellow pigments in the flour. Xanthophylls dominate the yellow pigments present.  Maturing agents 1. Potassium bromate (at levels less than 50 ppm), 2. Ascorbic acid (at levels less than 200 ppm), which accelerate the natural aging process of the flour and improve baking quality. Acetone peroxide, function as both bleaching and maturing agents.  Although both maturing and bleaching can be accomplished naturally by storing flours for several weeks to months. Flours may also be supplemented with enzymes, such as amylases and lipooxygenases, that improve their bread making performance.  Lipooxgenases, added as soy flour, function as bleaching agents and dough improvers. Addition of α-amylase, in the form of diastatic malt or a fungal supplement, corrects a flour deficiency. Enrichment, when added at the flour mill, is usually in the form of a premix containing the required nutrients. The five required nutrients include thiamine, riboflavin, niacin, iron, and folic acid. FLOUR SELECTION AND FUNCTIONALITY In general, the proximate composition of the flour depends primarily on the type of wheat. Hard wheat flours, such as hard red winter (HRW) and hard red spring (HRS) wheat, are about 82% starch, 12.5% protein, 3.5% fiber, 1.5% lipids, and 0.5% ash. These flours are preferred for bread making. PROTEINS Differences in protein content and quality among wheats affect loaf volume and the fineness, uniformity, and extensibility of the crumb grain. For bread production, good quality protein at about the 12% level is desirable.  Factors influence the protein quality 1. Wheat Type 2. Variety 3. Environmental Factors Including Nitrogen And Sulfur Availability, Heat Stress, Water Stress, And Insect Damage. 4. Storage Conditions Can Alter Protein Quality Postharvest.  Extract of protein fractions Wheat flour proteins have traditionally been sequentially extracted with salt solutions, 70% alcohol, 1% acetic acid, and reducing agents or alkali. Four fractions: albumin, globulin, gliadin, and glutenin are found.  The albumin and globulin fractions each account for about 10% of the total flour protein. Gliadin and glutenin are known as the gluten proteins; these storage proteins account for about 80% of the protein present in flour. Levels increase as total flour protein increases. The gluten proteins are responsible for dough properties.  Factors that influence bread making quality are: 1. Total amount of gluten proteins 2. Relative proportion of gliadin to glutenin present 3. The molecular weight distribution within each gluten protein fraction.  The important of flour enzymes. Lipooxygenases and amylases are often incorporated, and proteases may be added. Enzymes impact flour and dough properties, in particular dough elasticity and stickiness, gassing, and the final crumb structure in breads. It will added during either milling or bread production to enhance flour functionality. CARBOHYDRATES Starch forms the bulk of the bread dough and has several important roles in its structure. The surface of the starch granule interacts to form a strong union with gluten. Gelatinization is the process in which starch granules absorb water, swell, and break down, releasing amylose from the granule. Gelatinization of the starch, which occurs at 60–70°C (140–158°F), allows the gas-cell film to stretch.  Amylases can hydrolyze α-1,4-glycosidic linkages in carbohydrates, including starch. In flour, this activity is influenced by the degree of starch damage during the milling process. When damaged starch is hydrolyzed by amylase, absorbed water is released, making the dough softer.  Amylases, which produce maltose subsequently used in fermentation, may be present naturally or added during flour milling and/or bread production. Any residual sugar remaining post-fermentation can participate in the Maillard reaction during baking. Although wheat flour contains significant amounts of β-amylase, it is usually deficient in α-  In addition, microbial amylases, which are added by the baker or miller, have become available in recent years. Both water-soluble and water-insoluble hemicelluloses are present in wheat flour. This flour component is often referred to as pentosans because polymers of the pentose sugars D-xylose and L- arabinose dominate.  Water-insoluble pentosans 1. improve crumb uniformity 2. elasticity, 3. deleterious effects on crumb grain and texture Water-soluble pentosans 1. help regulate hydration, 2. dough development characteristics, 3. dough consistency. LIPIDS Each lipid fraction is composed of polar and nonpolar lipids, although the ratio differs among lipid fractions. 1. The polar lipids include glycolipids and phospholipids. 2. The nonpolar lipids are mainly triglycerides. Glycolipids 1. play an important role in dough development. 2. The glycolipids are bound to gliadin through hydrogen bonding and to glutenin through hydrophobic interactions in the dough OTHER ESSENTIAL BREAD INGREDIENTS 1- WATER Water is the most common liquid used in commercial baking. It comprises approximately 33–40% of the dough by weight. Water 1. responsible for hydration of the dry ingredients in the bread formula 2. forming the gluten complex during mixing. 3. serves as a dispersing medium for other ingredients, including yeast, 4. serves as a solvent for solutes (salt, sugar).  Mineral salts naturally occurring in water may affect bread dough properties. Hard waters containing high levels of calcium and magnesium ions may toughen the gluten, resulting in a tightening effect on dough. Soft waters, which lack these minerals and may be slightly acidic, may produce soft, sticky dough with impaired gas retention.  The pH of natural water is between 6 and 8; most municipal water supplies are adjusted to a pH between 7.1 & 8.5. Chilled water is often used in commercial operations to avoid excessive heat from mixing and dough development process. Temperatures above 27°C during dough development may over stimulate the yeast and adversely affect the gluten and starch. 2- YEAST The primary baker’s yeast is Saccharomyces cerevisiae. Several different strains are available. Different available forms 1. Compressed, 2. Active dry, 3. Instant. The three major functions: 1) leavening, 2) dough maturation 3) flavor development. Leavening involves the enzymatic conversion of fermentable sugars into ethanol and carbon dioxide.  Mechanism of bread production 1. sucrose is converted to glucose and fructose by invertase 2. maltose is hydrolyzed to glucose by maltase. Both invertase and maltase are yeast cell enzymes. 3- SALT Salt (sodium chloride) The three major functions in yeast-leavened breads: 1) Flavor 2) Inhibition or control of yeast activity 3) Strengthening of gluten.  In the absence of salt, the crumb of the baked loaves has an open grain and poor texture. The strengthening effect may be through direct interaction with the flour proteins. Salt’s effects on dough simulate those of oxidizing agents. OPTIONAL INGREDIENTS A. SUGAR Sucrose or corn syrup is usually incorporated in yeast- leavened breads to 1. Increase the rate of initial fermentation; 2. Amylolytic activity is required to produce a substrate for the yeast. Flavor and color effects are also found when sugar is incorporated at higher levels. In commercial yeast-bread production, liquid sugars are often used. B. FATS Desirable qualities are achieved when 2–5% fat on a flour-weight basis is incorporated. Bread volume increases by 15–25% because fat allows the dough to expand longer prior to setting. Palatability is also improved with fat incorporation into bread products. The grain is more uniform, fineness is increased, moisture perception is increased, and texture is softened. Flavor may also be enhanced. C. YEAST FOODS Yeast foods, a mixture of inorganic salts, are added for two major purposes: (1) to adjust the mineral composition of water (2) to provide nitrogen and minerals for yeast. Typical active ingredients 1. Yeast nutrients (ammonium salts) 2. Oxidants (usually potassium bromate or iodate), 3. pH regulators. D. SURFACTANTS Surfactants (or surface-active agents) act primarily as dough conditioners and staling inhibitors. Use of surfactants in yeast-leavened breads 1. Increase in bread volume, 2. A crust and crumb that are more tender, 3. A finer and more uniform crumb cell structure, 4. Staling inhibition. D. SURFACTANTS The most commonly used surfactants 1. mono- and diglycerides, which primarily contribute softness. 2. Sodium stearoyl lactylate (SSL), another widely used surfactant, complexes with gluten proteins during gluten development, strengthening the dough.  Dough strengtheners 1. Lecithins 2. Ethoxylated monoglycerides 3. Sorbitan monosterate 4. Diacetyl tartaric esters of mono- and diglycerides. Surfactants are amphiphilic, that is, they have both hydrophilic and hydrophobic groups. Therefore, surfactants serve as a bridge between immiscible phases. E. MOLD INHIBITORS Commercial bakery products, including breads, usually contain mold inhibitors. 1. Calcium propionate, a naturally present metabolite in Swiss cheese, is most commonly used in yeast-leavened products. Typical levels are between 0.25 and 0.38% flour- weight basis in breads and rolls. 2. Sorbates may also be used as mold inhibitors. F. MILK PRODUCTS Incorporation of milk products in yeast-leavened bread can improve both its nutritional and its eating quality. Type of milk products 1. Nonfat dried milk 2. dairy blends, 3. dairy substitutes  Dairy substitutes may include 1. Soy 2. Corn flours, 3. Soy protein. Typical levels of up to 6% on a flour weight basis are used. Nonfat dried milk incorporation at the 6% level reportedly 1. increased loaf volume 2. improved texture, crust color Bread production procedures Food processing Dr. Mohammed Alsebaeai Prof. Abdaljalil Darhm BREAD PRODUCTION PROCEDURES The sponge and dough method is the most popular bread production method. It yields soft bread with a fine cell structure and a well- developed flavor. SPONGE FORMATION AND FERMENTATION A portion of the flour (50–70% of the total), part of the water, the yeast, the yeast food, and any enzyme supplement used (step A in the Fig.) are mixed to form a smooth, homogenous mass. Gluten development is limited to that necessary to retain the gas produced by the fermenting yeast. This undeveloped dough is the sponge (step B in the Fig.). SPONGE FORMATION AND FERMENTATION Consistency ranges from stiff to soft, depending on the proportion of ingredients incorporated. The major fermentative activity of the yeast occurs in the sponge.  The sponge is typically allowed to ferment for three to five hours at 23–26°C and 75–80% relative humidity (step C in the Fig.). Fermentation time increases as the percentage of the flour incorporated decreases. During fermentation, the volume of the sponge increases four to five times and the sponge ultimately collapses.  pH is reduced with fermentation, and gas retention properties of the flour, vigorous yeast action, and flavor are developed. The desirable temperature for the fermented sponge is about 30°C. ADDING AND MIXING THE NONSPONGE INGREDIENTS The fermented sponge is returned to the mixer and combined with the remaining ingredients, except salt (step D in the Fig.). Salt is typically incorporated during the last two to three minutes of mixing. DOUGH DEVELOPMENT Mixing continues until optimum development or optimum hydration has occurred. The objective of mixing is to uniformly blend all the dough ingredients. This produces wet and sticky dough. As mixing continues and the gluten structure begins to form, the dough becomes drier and more elastic, and the dough mass becomes cohesive.  Over mixing results in dough that is increasingly less elastic and more soft and extensible. Over mixed dough will pull into long, cohesive strands. Continued mixing results in dough disintegration. Neither over mixed nor under mixed doughs hold up well in subsequent bread production operations. Factors that influence the time required for development 1) flour strength, 2) oxidizing and reducing agents, 3) time of salt addition, 4) enzyme supplementation, 5) temperature, 6) absorption level, 7) sponge consistency, 8) pH. Dough makeup dough division and rounding The first step in dough makeup is dividing the bulk dough into individual units of predetermined size (step E in the Fig.). Because dough is divided on a volumetric basis rather than by weight, the entire process must occur within 20 minutes to ensure individual units of equal size. INTERMEDIATE PROOF The rounded dough pieces are allowed to undergo a brief rest period. This recovery period usually lasts from 4 to 12 minutes, often under ambient temperatures and humidity conditions. SHEETING, MOLDING, AND PANNING First, the dough is sheeted or passed between closely spaced rollers to yield a thin and uniform dough layer. This step expels gas and redistributes gas cells, influencing final crumb grain. Next, the sheeted dough is curled into a relatively tight cylinder. FINAL PROOFING Final proofing conditions include temperatures in the range of 32–54°C) and a relative humidity of 60–90%. Proof times typically range from 55 to 65 minutes (step I in the Fig.). Generally, dough units are proofed to height or volume rather than for a fixed time. The dough has limited flow properties; thus, the volume increase is due to expansion. FINAL PROOFING Flour strength, oxidant and dough conditioner selected, melting point of shortening selected, and conditions during dough development and makeup (including the degree of fermentation) all influence the final proofing conditions chosen. FINISHED PRODUCT BAKING Baking time and temperature are influenced by dough formulation. Lean doughs are baked at higher temperatures for shorter periods of time. Rich doughs, high in sugar and dairy ingredients, will brown excessively if baked under conditions used for lean doughs. The first change in the panned dough unit is the formation of an expandable surface skin. STALING Deterioration in quality…. It includes loss of flavor, toughening of the crust, firming of the crumb, an increase in crumb opacity, and a decrease in soluble starch. During staling, the crust toughens due to the migration of water from the crumb to the crust. STALING Deterioration in quality…. The result is a soft and leathery crust and a firm crumb. Resistance of the bread crumb to deformation (firmness) is the attribute most commonly used to assess staling. Firmness is assessed by sensory evaluation as well as with instruments.  Bakery: Muffins A muffin is an individual-sized, baked quick bread product. The name “muffin” either comes from the German word “muffe” or from the French word “moufflet”, meaning soft bread.  HISTORY OF MUFFINS Originating in London. Made from yeast dough, (originating in London) Described as a quick bread since “quick- acting” chemical leavening agents are used instead of yeast. What is Chemical Leavening? Chemical leavening is a mechanism used in the baking industry to provide volume through the release of gases to enhance the eating quality of baked goods. Chemical leavening agents added to dough to produce 1. carbon dioxide 2. water vapor 3. ammonia. What is Chemical Leavening? These gases are responsible for 1. Expansion, 2. Flavor, 3. Color 4. Crumb grain size 5. Tenderness  Mechanism of chemical leavening Chemical leavening can be achieved by producing two types of gases: CO2 and NH3. These may be released by the following methods, combined or alone: 1. Decomposition reaction of ammonium bicarbonate or ammonium carbonate in the presence of heat. It will produces Ammonia carbon dioxide water.  Mechanism of chemical leavening 2. Reaction of an acid with a base compound. Combining a leavening acid with baking soda in the presence of moisture undergoes an exothermic reaction to produce Neutral salt Water Carbon dioxide  Classification of Chemical leaveners 1- Fast-acting: systems such as sodium bicarbonate- monocalcium phosphate monohydrate 2- Slow-acting: typically use a combination of sodium bicarbonate and sodium pyrophosphate 3- Double-acting consist of a mixture of sodium aluminium sulfate and monocalcium phosphate. https://upload.wikimedia.org/wikipedia/commons/thumb/b/bb/BlueberryMuffin.jpg/200px-BlueberryMuffin.jpg HEALTH CONCERNS Obesity Diabetes Cardiovascular diseases, Cancer Stroke. Malnutrition. FOOD LABELING AND HEALTH CLAIMS Information required on the nutrition facts portion of the food label are 1. the serving size 2. the amount per serving of calories 3. protein 4. fat 5. saturated fat 6. Cholesterol 7. Carbohydrates 8. fiber, sodium, calcium, vitamins A and C, and iron. 1. Organic fruits and vegetables are produced without using pesticides, or sewage sludge–based fertilizers. 2. Animal products identified as organic come from animals given organic feed but are not given antibiotics or growth hormones. 3. list all ingredients known to cause adverse responses in those with food allergens or sensitivities. 4. Food processing plants are required to follow GMP to avoid possible cross-contamination  Raw Materials Preparation: Selection and Scaling of Ingredients Cake-type muffins made by large commercial bakeries Bread muffin is made in the home or small institutions The differences between cake and bread muffins are that cake muffins are higher in fat and sugar and use soft wheat flours.  Ingredient formulas used by commercial bakeries are based on the weight of flour at 100%. The amounts of other ingredients are a percentage of flour weight (baker’s percent). For example... % of the ingredient= (total wt. of muffin ingredient ÷ total wt. of flour) × 100 FLOUR Flour represents 30 –40% of the total batter weight in most cake muffins. Most muffin formulas contain a blend of cake or pastry flour and a high-protein flour such as bread flour. The protein in flour is needed to provide structure in quick breads made with limited amounts of sugar. SUGAR Amounts of sugar in muffins range from 50 to 70%, based on flour at 100%. Type of sweeteners 1. Corn syrup 2. Molasses 3. Maple sugar 4. Fruit juice concentrates, 5. Honey are used as sweeteners for flavor variety.  The benefit of Sugar 1. Sugar contributes tenderness, crust color, and moisture retention in addition to a sweet taste. 2. Promotes tenderness by inhibiting hydration of flour proteins and starch gelatinization. 3. Maintains freshness because of Sugar is hygroscopic. 4. It contribute characteristic flavors and browning.  Sugar substitutes Sugar substitutes such as 1. acesulfame-K 2. sucralose c Sugar substitutes, however, do not contribute to tenderness, browning, or moisture retention The shelf life of muffins prepared without sugar would be very limited. FAT Muffins contain 18–40% fat based on flour at 100%. Type of fat used 1. shortening 2. vegetable oils  Benefit of fat 1. Fat contributes to the eating qualities of tenderness, flavor, texture, and a characteristic mouthfeel. 2. Fat keeps the crumb and crust soft and helps retain moisture, and shelf life.  Fat substitutes 1. Carbohydrate and lipid-based fat replacers can be used to prepare muffins acceptable to the consumer. 2. Lipid-based fat replacers that have the same chemical and physical characteristics as triglycerides are described as fat substitutes. 3. Monoglycerides, diglycerides, and modified triglycerides are examples of fat substitutes Fat substitutes can be divided into four categories based on the food component from which they are derived. Category Type and example Function Cellulose (Vivapur) Dextrins, modified starches (Stellar) Fruit-based fibre (WonderSlim) Binder, body, bulk, flavor, Carbohydrate- Grain-based fibre (Betatrim) moisture retention, mouth based Hydrocolloid gums feel Maltodextrin (Maltrin) Pectin (Grinsted) Microparticulate protein (Simplesse) Mouth feel, water-binding, Protein-based Modified whey protein reduce syneresis concentrate (Dairy-Lo) Altered triglycerides (Caprenin) Fat-based Sucrose polyesters (Olean) Emulsion, mouth feel Carbohydrate and protein (Mimix) Flavour, texture, mouth feel, Combination Carbohydrate and fat water retention (Optamax)  Leavening agents The amount of baking powder used in muffins varies between 2 and 6% based on flour at 100%. Gases released by a leavening agent influence 1. Volume 2. Cell structure. Double-acting baking powder (most commonly used in muffins) contains both slow- and fast-acting acids.  An example of a formulation to neutralize sodium bicarbonate is a mixture of slow and fast-acting 1. Acids—monocalcium phosphate monohydrate (a fast- acting acid) 2. Sodium aluminum sulfate (a slow-acting acid). Baking soda is used in addition to double-acting baking powder when muffins contain acidic ingredients such as sour cream, yogurt, buttermilk, light sour cream, molasses, and some fruits and fruit juices.  Excess sodium carbonate can cause 1. A soapy 2. Bitter flavor 3. A yellow color because of the effect of an alkaline medium on the anthoxanthin pigments of flour. 4. A coarse texture 5. Low volume because of an overexpansion of gas Inadequate amounts of baking powder 1. That will low volume of muffin. WHOLE EGGS Liquid eggs contribute 10–30% of muffin batter based on flour at 100%, Dried eggs contribute 5–10%. Benefit of egg 1. Flavor 2. Color 3. A source of liquid 4. The protein in egg white coagulates to provide structure WHOLE EGGS Adding egg whites to muffin batter provides structure to the finished product and a muffin that is easily broken without excessive crumbling. Substituting egg whites for whole eggs, however, will result in a dry, tough muffin. Fat in the yolk acts as an emulsifier and contributes to mouthfeel and keeping qualities. NONFAT DRY MILK POWDER Milk powder represents 5–12% of the muffin batter based on flour at 100%. Milk powder is added to dry ingredients, and water or fruit juice is used for liquid in muffin formulas. Benefit of milk 1. Binds flour protein to provide strength, body. 2. Adds flavor and retains moisture. 3. Contributing color as maillard browning occurs. SODIUM CHLORIDE The amount of NaCl in muffins is 1.5–2%. Function of NaCl 1. Enhance the flavor of other ingredients. 2. Enhance texture LIQUIDS Functions of liquid 1. Dissolving dry ingredients, 2. Gelatinization of starch, 3. Providing moistness in the final baked product. Insufficient liquid results 1. incomplete gelatinization of the starch and a muffin 2. insufficient structure to support expansion of air volume. 3. The muffins will have nonuniform cell structure 4. Overly crumbly texture, 5. Low volume ADDITIONAL INGREDIENTS Additional Ingredients such as 1. Bananas 2. Shredded carrots 3. Zucchini. Added flavorings include 1. Cinnamon 2. Nutmeg 3. Allspice, 4. Cloves, 5. Orange 6. Lemon zest (peel or rind). ADDITIONAL INGREDIENTS Other ingredients are often added to muffins for 1. Flavor 2. Texture 3. Color 4. Increase Specific Nutrients Or Health Components Such As Fiber, Vitamins And Minerals, Or Antioxidants From Fruit And Vegetable Extracts.  PROCESSING STAGE 1: MIXING There are two primary methods for mixing muffins: 1) The cake method: This involves creaming sugar and shortening together, then adding liquid ingredients, and finally adding dry ingredients. 2) The muffin method: This involves two to three steps. First, dry ingredients are mixed together Second, shortening or oil and other liquids are mixed together; Third, the liquids are added to the dry ingredients and mixed until the dry ingredients are moistened.  Use a mixer on slow speed for three to five minutes. Inadequate mixing results in a muffin with a low volume since some of the baking powder will be too dry to react completely. STAGE 2: DEPOSITING The traditional size of muffins is two ounces, though muffins are marketed in a wide range of sizes, i.e. from 1/2 ounce to muffins 5 ounces or larger in size. Small batter depositors are available that will deposit four muffins at a time. STAGE 3: BAKING Many physical and chemical changes occur in the presence of heat to transform a liquid batter into a final baked muffin. Solubilization and activation of the leavening agent generates carbon dioxide that expands to increase the volume of the muffin. Gelatinization of starch and coagulation of proteins provide permanent cell structure and crumb development. Caramelization of sugars and Maillard browning of proteins and reducing sugars promote browning of the crust. Reduced water activity facilitates Maillard browning as well as crust hardening. STAGE 4: COOLING Products should be cooled prior to wrapping. This allows the structure to “set” and reduces the formation of moisture condensation within the package. Condensed moisture creates an undesirable medium that promotes yeast, mold, and bacterial growth and spoilage. STAGE 5: PACKAGING May be wrapped individually, or transferred into plastic form trays for merchandizing. The shelf life of muffins is three to five days for individually wrapped muffins and four to seven days for six or more muffins packaged in trays and wrapped in foil or plastic wrap.  The storage life of muffins is significantly influenced by exposure to oxygen and moisture. Cake muffins have a longer shelf life than bread muffins because of their high sugar content and lower water activity. Added ingredients, such as cheese, and dried fruits that are high in sodium or sugar content, reduce water activity and increase shelf life.  MUFFIN EVALUATION 1. Volume 2. Contour of the surface 3. Color of the Crust 4. Interior color 5. Cell uniformity and size 6. Thickness of cell walls 7. Texture 8. Flavor 9. taste, 10. Aroma 11. Mouthfeel Carbonated Beverages Food processing Dr. Mohammed Alsebaeai Prof. Abdaljalil Darhm  Beverages Nonalcoholic, Carbonated Beverages 1) History of soft drinks At ancient time, carbonated natural mineral waters were discovered although they weren’t usually used for drinking. In 1767, the British chemist Joseph Priestley was credited with noticing that the carbon dioxide (CO2) introduced into water gave a “pleasant and acidulated taste to the water in which it was dissolved”.  Beverages Nonalcoholic, Carbonated Beverages 1) History of soft drinks The history of carbonated soft drinks (CSDs) is somewhat sparse (existing only in small amounts) during its early evolution, but most agree that the development of CSDs is due, in large part, to pharmacists.  Soft drinks and hard drinks “Soft drinks,” a more colloquial yet very common name for carbonated beverages, Distinguish themselves from “hard drinks,” since they do not contain alcohol in their ingredient listing. These nonalcoholic, carbonated beverages are also called “pop” in some areas of the world, due to the characteristic noise made when the gaseous pressure within the bottle is released upon opening of the  Pop drinks These nonalcoholic, carbonated beverages are also called “pop” in some areas of the world, due to the characteristic noise made when the gaseous pressure within the bottle is released upon opening of the package. 2) Soft Drinks Facts and Figures Distribution of cans, PET (Polyethylene Terephthalate), and glass CSD packages 3) Carbonation Science RAW MATERIALS PREPARATION a) Concentrate Primary flavor components fall into three broad categories: they are simple mixtures, extracts and emulsions. 1) Simple mixtures: The simplest of the flavor categories to understand. They represent the minority of those in existence. A combination of miscible liquids or easily soluble solids are blended together to form a homogenous aqueous mixture. Because so many essential flavor oils are not readily water soluble, the beverage technologist must abandon the idea of the simple mixture for one of the other, more flexible categories of flavors. 2) Extracts: This category of flavors involves extracting the desired flavor constituents from essential oils. Simply put, the extraction solvent usually ethanol or propylene glycol to partition those flavor constituents that are soluble in the solvent, but not freely soluble in the water directly. In this way, these flavor compounds become fully dissolved in the ethanol first. Then, this ethanolic extract (which is, in effect, an ethanolic solution of the flavor compounds) is added to water. 3) Emulsions: In the carbonated beverage industry, oil-in-water (or o/w) emulsions are the standard. This model involves an oil (lipophilic) internal phase and an aqueous (hydrophilic) external phase being made compatible by the use of a surfactant (or emulsifier). Surfactants Surfactants are compounds that are amphiphilic; that is, there are both hydrophilic and lipophilic portions of the same molecule. This facilitates a decrease in the surface tension when oil and water are mixed together, and allows the lipophilic portion to align with the oil while allowing the hydrophilic portion to align with the water. b) Water It represents anywhere from 85 to near 100% of the finished product. Though it might be safe to drink and aesthetically pleasing to the consumer (potable and palatable), it is not usually of the high quality needed for producing a finished carbonated beverage product and assuring the beverage a long shelf life.  Types of treatment of water 1. Conventional lime treatment systems (CLTS), used for water softening via adding KoH to remove Calcium and Magnesium, 2. Membrane technology 3. Ion exchange. Table 1. Advantages and disadvantages of CLTS c. Sweeteners Sucrose, Hi Fructose Corn Syrup Aspartame, acesulfame potassium … d. Carbon dioxide CO2 It is save, and can be obtained form appropriate sources. Specifications of the gas shall be considered to comply with regulations. SYRUP PREPARATION Most carbonated beverage formulas begin with a simple syrup, which is usually a simple combination of the nutritive sweetener (sucrose, HFCS, MIS) and treated water. In some cases, it may also contain some of the salts outlined in the specific beverage document, depending on the order of addition that is required. SYRUP PREPARATION Once the sweetener is completely dissolved, and the simple syrup is a homogenous batch, then the flavor and remaining components are added to form the finished syrup. All simple syrup should be filtered before being pumped to the finished syrup blending/storage tanks. Moist sugar creates two immediate and serious problems: (1) Moist sugar can have high microbial counts, much of which will be yeast. Yeast is a serious problem to carbonated beverages, since it can lead to fermentation and eventual spoilage of the finished product. (2) Moist sugar makes accurate measuring difficult, since the moisture content is being weighed with the sucrose solids. This makes final control of the batch difficult and inconsistent. Using liquid sugars. There are three main types of liquid sugars that are used for syrup production: 1. liquid sucrose 2. medium invert sugar (MIS) 3. high fructose syrups. Making simple syrup from liquid sucrose is similar to the procedure employed when using granulated sugar. The first step is to check the Brix of the liquid sucrose to find out how much water must be added to the batch to bring the Brix of the simple syrup to the level required by the formula. Medium invert sugar (MIS) is resistant to microbial spoilage when being transported from supplier to plant, and while in storage. However, good sanitation procedures, as well as special precautions to prohibit secondary infection, are still required. When liquid invert shipments are received at the plant, they should be accompanied by an analysis sheet comparing the tank load against company standards. When testing for Brix, a correction factor must be used on refractometer readings to compensate for the non- sucrose solids that are a result of the inversion process. Using high fructose syrup (HFS). For liquid sugars in general, the analysis should confirm that the material is within standards. High fructose syrup is subject to crystallization, so storage temperatures should be controlled (generally maintained between 24°C and 29°C) by the use of indirect heating. As with MIS, when testing for Brix in HFS samples, a correction factor must be used on refractometer readings to correct to true Brix and compensate for the non- sucrose solids. CARBONATION The primary function of the carbonating unit (carbonator) is to add CO2 to the product. It must be carbonated to a level that, after filling and closing, results in a product within the standards for beverage carbonation. The product can be slightly precarbonated with CO2 injection and then exposed to a CO2 atmosphere directly where cooling is in progress. Other systems separate the carbonating and cooling steps.  FILLING, SEALING AND PACKAGING QUALITY CONTROL AND ASSURANCE FINISHED PRODUCT  Cheese Food processing Dr. Mohammed Alsebaeai Assistance Professor (Ph. D) in Food science Lebanese International University  What is Cheese According to the FDA, cheese is defined as a fresh or old product, solid or semi-solid, obtained from the coagulation of milk (through the action of rennet or other coagulant, with or without previous hydrolysis of lactose) and after separation of serum. Milk commonly used in making cheese is of cows (whole or skim) which gives a softer flavor of cheese and that of goat or sheep (in Mediterranean areas).  Origin of Cheese Origin of cheese is not very accurate but can be estimated between years 8000 BC and 3000 BC. Archaeological proof confirms that its use in ancient Egypt dates back to 2300 BC. It is said by ancient historians that Europe started production of cheese thereby making it a popular consumer product. CATEGORIES OF CHEESE Different ways to categorize cheese might include (1) Coagulation type, (2) Ripening method (3) Texture. 1- Coagulation Type Acid only. 1. Example Cottage cheese, cream cheese, and Neufchatel. higher moisture (50–80%) 2. contain significant quantities of residual lactose. Heat and acid. 1. Ricotta and queso blanco 2. a bit lower in moisture (50–70%).  Acid and enzymes. 1. lactic acid bacteria (LAB), 2. A coagulating enzyme (rennet or chymosin) 3. Cheddar, Swiss style, brick, and many other cheeses 2- Ripening Method Fresh un-ripened cheeses. 1. consumed shortly after manufacture. 2. Mozzarella, cottage, ricotta, and cream Soft, surface mold ripened cheeses. 1. Camembert and Brie 2. LAB to produce acid in the milk 3. an enzyme (rennet or chymosin) These cheeses have little residual lactose. - Internally mold ripened. 1. Gorgonzola, Roquefort, and blue 2. ripened throughout by the growth of the blue green mold Penicillium roquefortii. 3. The curd is formed by acid produced from bacteria, and coagulation occurs with the addition of rennet. - Surface bacteria ripened. 1. Limburger, brick, Port du Salut and 2. rely upon a surface smear of bacteria and yeasts to form the flavor and texture of these cheeses. 3. The curd is formed by LAB and rennet. 3- Texture Very hard. 1. Parmesan and Romano 2. the curd is cooked to a relatively high temperature (50°C), causing it to dry out. 3. The aging process of these cheeses is typically over one year after the curd has been formed. 4. Moisture content is usually less than 32%. Hard. 1. Cheddar, Colby, Swiss style, Gouda, and many other cheeses 2. Moisture ranges from 37 to 45%. 3- Texture Semisoft. 1. This is a very diverse group of cheeses and includes Gorgonzola, Limburger, brick, and Muenster. 2. The texture is relatively soft and nearly spreadable. Moisture content is in the 43–50% range. Soft. 1. These cheeses are characterized as being relatively easy to spread. 2. Brie, cream, Neufchatel, and ricotta are examples of these cheeses, 3. a moisture content up to 55%.  Composition of Cheese Name Moisture Fat Protein Ash and Salt Brick 42.5 30.7 21.1 3 Camembert 47.9 26.3 22.2 4.1 Cheddar 36.8 33.8 23.7 5.6 Cottage 69.8 1 23.3 1.9 Cream 42.7 39.9 14.5 1.9 Edam 38.1 22.7 30.9 6.2 Limburger 54.8 19.6 21.3 5.2 Parmesn 17 22.7 49.4 7.6 Roquefort 38.7 32.2 21.4 6.1 Swiss 33 30.5 30.4 4.2 Gouda 38.1 24.5 29.6 6.1  Essential process steps cheese making 1. Pretreatment of milk 2. Clouting of milk 3. Removal of whey 4. Acid production 5. Salting 6. Fusion of curd grains/ pressing 7. curing  Manufacturing of Cheese by Traditional Method Milk Filtration/Clarification Standardization (3-4 % fat) Pasteurization (630 C/30 min) Cooling (310C) Starter Addition (Streptococcus thermophillius and Lactobacillus bulgaricus (1:1) @ 1-2%) Rennet addition (1.5 g/100 L milk)  Cutting Cooking (42-440 C) Draining Cheddaring (0.70% acidity) Milling Plasticizing/stretching under hot water (80-850C) Moulding  Cont. Brining (20-22% chilled brine) Packaging Manufacturing of Cheese by Direct Acid Method Milk Filtration/Clarification Standardization (3-4 % fat) Pasteurization (630 C/30 min) Chilling (4-80C) Acidifying (To pH 5.2-5.4 with 25-50 % HCL @ 2.0-3.5 ml conc. Acid/L milk) Heating (28-300 C )  Rennet addition (0.5-0.75 g/100 L milk) Cutting Cooking (42-440 C) Draining Plasticizing/stretching under hot water (80-850C) Moulding Brining (20-22% chilled brine) Packaging  Functional properties of Cheese 1. Color varies from orange to white. 2. Meltability- depend on casein Network 3. Free oil formation- gives a greasy appearance 4. Browing- Occurs at high Temperature.  Factor affecting of cheese making 1. Enzyme added 2. Acid developed 3. Time-temp. combination for cooling of curd 4. Amount of salt added 5. Moisture content of cheese 6. Pressing of curd 7. Ripening condition 8. Surface treatment  Health aspect of cheese 1. Cheese is great for your teeth. 2. Cheese is even better for your bones. 3. Cheese helps pregnancy go more smoothly. 4. Cheese may be good for your skin 5. Cheese might prevent cancer. 6. Cheese is good for people who suffer from migraine headaches. 7. Cheese can boost your immune system 8. Cheese is a leading product for people who need to gain weight  Health risk of eating cheese According to a study published in the "Journal of the National Cancer Institute," cheese and other dairy products may actually raise the risk of breast cancer. A study published in "Nutrition and Cancer" also came to the same conclusion. Other studies link cheese to lymphoid cancers and lung cancer.  Health risk of eating cheese The Physicians Committee on Responsible Medicine warned in "The New York Times" that cheese can contribute to the development of colic, allergies and digestive problems. The Center for Science in the Public Interest warns that the consumption of cheese is giving heart attacks to many Americans because of its high-fat content.  BUTTER Food processing Dr. Mohammed Alsebaeai Assistance Professor (Ph. D) in Food science Lebanese International University  Introduction Butter is essentially the fat of the milk. Usually made from sweet cream and is salted. Also be made from acidulated or bacteriologically soured cream. Salt less or sweet butters are also available.  Introduction In general use, the term "butter" refers to the spread dairy product when unqualified by other descriptors. The word commonly is used to describe pureed vegetable or seed and nut products such as peanut butter and almond butter. It is often applied to spread fruit products such as apple butter.  Introduction Butter contains fat in three separate forms: 1) free butterfat 2) butterfat crystals 3) undamaged fat globules  Buttermilk The buttermilk is drained off; sometimes more buttermilk is removed by rinsing the grains with water. Then the grains are "worked": pressed and kneaded together.  Fermentation process The fermentation process produces additional aroma compounds, including diacetyl, which makes for a fuller-flavored and more "buttery" tasting product. Today, cultured butter is usually made from pasteurized cream whose fermentation is produced by the introduction of Lactococcus and Leuconostoc bacteria.  CLASSIFICATION The main kind of butter are follows- 1. Pasteurized cream butter 2. Ripened cream butter 3. Salted butter 4. Unsalted butter 5. Sweet cream butter 6. Sour cream butter 7. Fresh butter 8. Cold storage butter 9. Dairy butter 10. Creamery butter.  https://upload.wikimedia.org/wikipedia/commons/thumb/f/fd/Western-pack-butter.jpg/225px-Western-pack-butter.jpg https://upload.wikimedia.org/wikipedia/commons/thumb/2/2a/Butter_melt_with_sugar.jpg/220px-Butter_melt_with_sugar.jpg https://upload.wikimedia.org/wikipedia/commons/thumb/4/43/Butterschmalz-2.jpg/150px-Butterschmalz-2.jpg  COMPOSITION OF BUTTER Commercial butter is about 80% butterfat and 15% water; traditionally made butter may have as little as 65% fat and 30% water. COMPOSITION OF BUTTER Constituent Percentage Butter fat 80.2 Moisture 16.3 Salt 2.5 Curd 1.0  Flow Diagram for Butter Manufacturing Milk receipt ↓ Cream receipt pre-treatment (35-40 oC) ↓ ↓ Neutralization Cream Separation (centrifugation) ↓ ↓ Standardization (30-35 % Fat) ↓ Pasteurization (82 -88 oC for no hold) ↓ Cooling (5-10 oC) (Ripening 22-33 0C) Ageing (5-10 0C) ↓ Churning, working, Salting and Kneading ↓ Freezing, Storage ↓ Bulk packaging and Storage (-23 to 29 oC) ↓ Consumer packaging  Diagram of a continuous butter-making machine: Churning cylinder 1; separating section 2; squeeze-drying section 3; second working section 4; injection section 5; vacuum working section 6; final working stage, 7.  Churning Agitation of cream at a suitable temperature until the fat globules adhere forming larger mass and until a relatively complete separation of fat and serum occurs.  Factors affecting churnability ❖ Chemical composition of fat ❖ Size of fat globules ❖ Viscosity of cream ❖ Temperature of cream at churning ❖ Fat % of cream ❖ Acidity of cream ❖ Load of churn ❖ Nature of agitation ❖ Speed of churn  Washing Objective To remove all loose buttermilk adhering to butter grain To correct the defects in firmness of butter To decrease the intensity of off flavors Addition of chilled water at 1 – 2 oC  Salting Addition of salt to butter (2-2.5 % to butter fat) Objectives To improve the keeping quality To enhance the taste To increase the overrun Methods of salting Dry salting Wet salting Brine salting  Working of butter (Kneading of Butter) Objectives To completely dissolve and uniformly distribute and incorporate salt To expel buttermilk and to control the moisture content in butter To incorporate the added make up water To bring butter grains together into a compact mass  PACKAGING Packaging materials are- Wood or timber Parchment paper Aluminium foil Tin-plate cans  STORAGE The temperature of commercial cold storage of butter ranges from -230c to -290c. There is invariably some flavor deterioration of butter while it is in commercial cold storage.  USES OF BUTTER There are many uses of butter, some important uses are as - Direct consumption with bread. Uses of the preparation of sauces. Act as a cooking medium. In the baking and confectionary industries. In the manufacturing of ice cream, butter oil and ghee.  Ice Cream Food processing Dr. Mohammed Alsebaeai Assistance Professor (Ph. D) in Food science Lebanese International University  Ice Cream Ice cream is a frozen food made from milk fat, milk solids-not-fat, sweeteners, and flavorings; a variety of fruits, nuts, and other items also may be added. Reduced calorie ice creams, which must meet the nutrient claims that comply with "reduced fat. https://upload.wikimedia.org/wikipedia/commons/thumb/8/86/Black_sesame_soft_ice_cream.jpg/220px-Black_sesame_soft_ice_cream.jpg https://upload.wikimedia.org/wikipedia/commons/thumb/a/a5/Italian_ice_cream.jpg/220px-Italian_ice_cream.jpg https://upload.wikimedia.org/wikipedia/commons/thumb/9/9d/RaspberrySherbet.jpg/170px-RaspberrySherbet.jpg https://upload.wikimedia.org/wikipedia/commons/thumb/3/37/Helados.jpg/220px-Helados.jpg The steps in the manufacturing of ice cream 1- Blending of the mix ingredients. 2- Pasteurization. 3- Homogenization. 4- Aging the mix. 5- Freezing. 6- Packaging. 7- Hardening. Raw Materials Preparation Typical ingredients are milk fat sources, milk solids sources, sweeteners, stabilizers and emulsifiers, colors, flavors, particulate materials; nuts, fruits, and candy pieces. Ingredients can arrive as liquids that may require refrigerated storage, powders that may only require ambient storage, or frozen products that may require frozen storage. Typical Ingredients, Usage Levels, and Sources for Vanilla Ice Cream Mixes  Optional ingredients 1. Whey products 2. Milk protein sources; 3. Hydrocolloids such as alginates, and carboxymethyl cellulose; 4. Flavors, and colors Generally, ingredient selection is based on price and availability.  For instance, liquid sugar sources may be easier to handle in one ice cream facility, and thus, syrups may be an important part of a formulation at that facility, but not at a facility that predominately uses dried products. Most plants formulate and manufacture "white" and "chocolate" mixes that will serve as the base for many different flavors of ice cream. For example, a white mix could be the base for cookies and cream ice cream as well as a strawberry ice cream. The difference is the flavoring, coloring, and particulate added to the mix to make the final product. Processing Stage 1: The main steps of ice cream processing are shown here below: BLENDING Blending disperses the dry ingredients into the liquid components for creation of a product that is as uniform as possible.. Liquid ingredients are normally blended in a mix vat, with gentle agitation to prevent degradation of the milk fat. Advantages of blending include 1. Production of a homogeneous product, 2. Enhanced powder hydration, 3. Minimization of product losses by preventing dry ingredients from sinking to the bottom and not being fully incorporated into the final product. Disadvantages of blending 1. Need for equipment, 2. Additional process time, 3. Additional energy input.  Because dried ingredients often are used in the ice cream mix, adequate and thorough blending through agitation or recirculation is necessary to:.. 1. Initiate protein and polysaccharide rehydration. 2. Suspend colloidal materials. 3. Solubilize sugars and salts. PASTEURIZATION The purpose of pasteurization is to inactivate any and all pathogens that are in the mix. Type of pasteurization - Batch pasteurization requires a minimum temperature of 68.3°C for 30 minutes. - High-temperature short-time (HTST) pasteurization requires a minimum of 79.4°C for 25 seconds. HTST is the most commonly used pasteurization choice because of its energy efficiency and speed. A small HTST pasteurizer is shown in the following figure.  An HTST pasteurizer for ice cream mix. In the HTST design, three heat exchange sections exist: regenerator, heating, and cooling. All three sections consist of stainless steel plates that channel the flow of product to prevent cross-contamination. HOMOGENIZATION Homogenization is the size reduction of particles into a more uniform distribution in the liquid phase of the system; the final result is a more consistent product. In the case of ice cream mixes, the homogenization creates smaller diameter milk fat globules (< 2 μm) that are more evenly dispersed, and thus aids in mix emulsion stabilization. The principle of homogenization is to force liquid to flow under high pressure through a narrow orifice, usually just slightly larger than the diameter of the particle to be homogenized.  Factors affect the overall homogenization 1. Pressure, 2. Temperature, 3. Orifice size, 4. Design.  The advantages of homogenization include 1. the greater surface area of the fat globules, 2. viscosity enhancement, 3. greater stability. Disadvantages 1. Homogenized milk fat is more sensitive to light-induced oxidation 2. Effect of protein stability  Because of their relatively high fat content, mixes are homogenized in two stages (two passes through the homogenizer); 1. the first stage is set at a pressure of 13–15 MPa, 2. the second at 3–5 MPa. Mix temperatures should be in the range of 50–66°C to assure efficient homogenization. COOLING After the mix is homogenized and pasteurized, it is cooled quickly to ≤ 7.3°C. The objective is 1. to cool the product as quickly as possible 2. maintain the cold temperature to prevent microbial growth or proliferation. Cooling is usually done with a heat exchanger, If the mix is commercially sterilized in a UHT system, the mix may not be required to be cooled to below 7.3°C: it may only be cooled to ambient temperatures (20–25°C) and then aseptically filled into containers, sealed, and then placed in storage.  Advantages of cooling 1. It is enhance food safety 2. It also initiates milk fat crystallization and water binding by polysaccharides and proteins. Disadvantages include 1. Energy, 2. Labor, 3. Time inputs, 4. The capital investment in equipment 5. maintenance and operation of equipment. Processing Stage 2 FLAVORING AND COLORING This subdivision occurs to meet daily production quotas, for example 1. 60% for vanilla, 2. 25% for chocolate chip, 3. 10% for strawberry, 4. 5% for mint chocolate chip. Thus, a designated amount of mix will be pumped into a flavor tank and adequately flavored and colored, as indicated in the product specifications and formulation sheets.  The main advantage of the flavor tank is 1. The production of a more homogenous product 2. Assuring that the product contains consistent flavor/color. Disadvantages are similar to those shared above: 1. Additional equipment to maintain and clean 2. A potential source of contamination.  Sufficient agitation ensures a homogenous product prior to freezing. Most flavors are suspended in an alcohol base, which could denature the casein proteins; thus, flavor addition should be done slowly. Because the mix ingredients have been pasteurized and homogenized, agitation control is not as critical as in the initial blending step, where excessive agitation may initiate undesirable chemical reactions, especially with milk fat. However, because the mix will not be heat treated prior to consumption, all ingredients (colorings, flavorings, particulates, variegates, etc.) added postpasteurization to the mix or ice cream must be of high quality to ensure a safe, wholesome ice cream product. FREEZING The purpose of freezing ice cream is 1. Two-fold formation of the foam structure 2. Initiation of the freezing process. Freezing in the ice cream industry refers to the process in which the temperature decreases from 4°C to approximately - 6°C with simultaneous air incorporation.  Advantages of quick freezing are the ability to incorporate air and initiate many small-sized ice crystals. The disadvantage of quick freezing is greater reliance on the equipment and auxiliary equipment (compressors, etc.) to maintain low temperatures. PACKAGING The purposes of packaging are 1. Product identity 2. Product integrity 3. Product safety Vanilla ice cream can be packaged into containers of many different sizes (single service 113 ml to 12.5 liter containers) and materials including 1. Paperboard 2. Plastic 3. Foil laminates.  Disadvantages 1. The added cost to the product, 2. Introduction of another "barrier" that will need to be further frozen. For ice cream, the packaging process needs to be rapid. The ice cream may be at - 6°C as it is discharged into the containers, and the exposure to warmer environmental temperatures in the manufacturing facility may result in melting; therefore, one production consideration is the need to package the product and move it into the hardening room quickly. HARDENING As soon as possible after packaging, ice cream is placed in a hardening facility, which is normally kept at -30 to -35°C or lower with forced air movement. The purpose of hardening is 1. to continue freezing the ice cream as quickly as possible 2. to minimize ice crystal size and stabilize the foam. 3. lactose crystallization  The advantages of hardening are preservation of ice cream and improved quality. Disadvantages of hardening It is associated with the cost of cold air space(s). Refrigeration and air movement are expensive and can be hazardous to the personal safety of workers. FROZEN STORAGE After leaving the hardening room, ice cream is placed in frozen storage. The desired storage temperature is - 15°C or less. The storage stability and quality of ice cream are highly dependent upon 1. Stabilizing the air cells 2. Ice crystals in the frozen form 3. Maintaining structure with cold temperatures. Fats: Edible Fat and Oil Processing Food processing Dr. Mohammed Alsebaeai Assistance Professor (Ph. D) in Food science Lebanese International University  BACKGROUND INFORMATION Fats and oils are both mixtures of triacylglycerides. Chemically, they are essentially the same, and the differentiation into fats and oils is mostly arbitrarily based on the physical state of the mixtures at room temperature, that is, if they are solid or liquid.  Fats: Edible Fat and Oil Processing BACKGROUND INFORMATION While it is obvious that room temperature in a tropical country might mean something very different than room temperature in a Scandinavian country, even within the United States, room temperature is lower in the winter than in the summer because humans consider a range of temperature of approximately 65–75°F (18–24°C) as comfortable. Thus, we will use the term fat throughout this chapter without consideration of whether the fat might be solid or liquid at room temperature.  Fats and oils are harvested from both the plant and the animal kingdoms. However, while we therefore ought to differentiate only between animal and plant fats, because of the unique composition of the fat of most fish, fats from fish are often categorized separately as marine oils. This separation also makes sense from a processing standpoint. The processing of fats is easy to comprehend and to remember because it is a logical progression of steps, which ultimately yield a pure (≥ 99.9%) shelf-stable product. RAW MATERIALS PREPARATION EXTRACTION The first step in fat production is the extraction or harvest of the fat. This is where the first major difference between animal, plant, and marine fats is encountered. The rendering of animal fat is similar for all animal sources. The fats from plant sources are extracted in numerous different ways. The goal of the extraction process is: 1. Highest yield 2. Least impurities Rendering of Animal Fat The fat rendered from animals is located in the adipose tissue of animals. Intramuscular fat, which is known to be in part responsible for the tenderness and juiciness of steaks, is not rendered for fat collection. The adipose tissue, which contains between 70 and 95% fat, is trimmed, washed, and ground. The fat is then rendered from the ground adipose tissue by a wet or a dry rendering method.  Wet rendering The most commonly used method is wet rendering with high heat (steam rendering). Steam is directly injected under high pressure into the trimmed fat, disintegrating the fat cells and releasing the fat. The layer of fat that rises to the top (tankage) is skimmed off and then centrifuged to get rid it of water, yielding 99.5% pure fat. Because of the treatment of the fat with water at high temperatures, some hydrolysis of the triacylglycerides into free fatty acids occurs, and a low-temperature wet rendering method has been developed.  The dry rendering The fat is extracted by drying the trimmed adipose tissue in steam- jacketed vessels. The fat is liquefied and drained off. The remaining tissue is pressed to extract the remaining fat. Rendering of Marine Fats (Oils) Marine fats have received considerable attention over the last two decades because they contain comparatively large amounts of long- chain omega-3 (also called n-3) fatty acids, which are indicated to have numerous health benefits. Marine fats are rendered similarly to other animal fats, one important difference exists. While land animals have clearly identifiable fat storage areas (the adipose tissue), fish do not. Rendering of Marine Fats (Oils) Fish are differentiated into lean fish and fatty fish. In the lean fish, such as cod, the fat is mostly stored in the liver, The fatty fish, such as herring, the fat is dispersed throughout the muscle tissue. The oil is rendered by pressing the steam-cooked fish and then separating the resulting liquid into aqueous and oil phases by centrifugation. The crude fish oil is highly susceptible to oxidation because of the omega-3 fatty acids and must be thoroughly refined before it can be used for human consumption.  Extraction of Plant Fats There are many methods for extracting fat from plants. The extraction of fat from plants requires extensive mechanical pretreatment of the plant tissue. Most plant fats are stored in the seeds, which can vary from soft- tissued fruits, such as avocadoes, to hard-shelled nuts.  The general cleaning step to remove foreign materials, such as sticks and stones The pretreatment may include 1. Peeling 2. Crushing 3. Shelling 4. Dehulling  As in the rendering of animal fat, some plants require a heat treatment (cooking) prior to the extraction. Cooking is usually done to 1. Coagulate proteins, 2. Rupture cell membranes, 3. Release fats out of protein lipid interactions, 4. Break emulsions in the oil seeds.  There are two major approaches for extracting the fat from the seeds: 1. Solvent extraction 2. Mechanical extraction (pressing). Pressing can be done in either 1. A batch process 2. A continuous process.  Continuous screw presses will extract the majority of the fat and leave a residual amount of fat in the seed below 5%. Solvent extraction, which is most commonly done with hexane, is more efficient than mechanical extraction by pressing and can reduce the amount of fat that remains in the seed to below 3%. Solvent extraction is more efficient than pressing, for seeds with a low initial amount of fat. Mechanical extraction works better for seeds with a high initial fat content.  This operating cost is another reason why it is more efficient to use mechanical extraction for seeds with a high fat content. Usually, the seed flakes are successively washed with recovered solvent in order to increase yield and efficiency. The continuous method is more common because of its higher efficiency. It involves a countercurrent extraction system: the flakes to be extracted are washed by solvent that already contains fat gained downstream in the extraction system.  The batch extraction system can also be set up as a countercurrent system by using solvent with an ever-increasing fat content to mix with flakes with lesser degrees of extraction. Although the fat extraction may yield fat with a purity of up to 95%, the remaining impurities in this crude fat extract make the fat highly susceptible to oxidation. After being extracted, the fat must be cleaned to remove these impurities. This obligatory cleaning process is commonly called refining. OBLIGATORY PROCESSING STEPS DEGUMMING The first step in cleaning the fat is usually degumming, which is the removal of phospholipids (sometimes incorrectly called “gums” because of functional properties that are similar to those of carbohydrate-based gums). Phospholipids have both lipophilic and hydrophilic moieties that make them excellent emulsifiers, but they also allow faster spoilage of the fat because they are more susceptible to oxidation than triacylglycerides. Most phospholipids found in crude oils are diacylglycerides which are called phosphatidic acids. Lecithin is choline attached to the phosphoric acid, resulting in phosphatidyl choline  DEGUMMING Lecithin is an important by-product of the degumming process. In degumming, the fat is heated to about 165°F (74°C) and a small amount of water (1–3%) is added, which causes hydration of the phospholipids, making them soluble in the water and insoluble in the fat phase. Other minor components, such as proteins and carbohydrates, are also removed as they enter the aqueous phase. Centrifugation is then used to separate the two phases.  NEUTRALIZATION The neutralization step is also often referred to as alkali refining. However, because the term refining also refers to all of the combined steps of fat purification, the use of the term neutralization is recommended in order to avoid confusion. Alkali Some extraction procedures will generate free fatty acids. due to enzymatic actions in the plant or animal tissue prior to extraction. Because free fatty acids are more susceptible to oxidation than triacylglycerides, removal of free fatty acids is essential for the manufacture of a shelf-stable product. The easiest way to remove free fatty acids is by neutralization with alkali, such as sodium hydroxide, which essentially results in the formation of soaps. The alkali must be in a low concentration to avoid saponification, that is, soap formation  The soaps are then removed by centrifugation, resulting in a fat with a free fatty acid content well below 0.05%. Recent research at many plants improved this process by using sodium silicate. The advantage of this new process is that 1. The sodium silicate neutralize the free fatty acids, 2. The excess sodium silicate an absorbent for the soap, allowing for removal of the soap by simple filtration instead of the more energy intensive centrifugation.  Distillation A different approach to getting rid of the free fatty acids is vacuum distillation, also called steam refining or physical refining. Free fatty acids are considerably more volatile than triacylglycerides and can be removed by a simple distillation procedure. The alkali neutralization step can be done without prior degumming The removal of free fatty acids by distillation is problematic when a crude fat has been insufficiently degummed because the heating step will cause foaming and darkening of the fat. BLEACHING With few exceptions, such as olive oil, consumers expect their fat to have little or no color. In addition, many pigments are pro-oxidants that will make a fat more susceptible to oxidation. Thus, most fats and oils are bleached in order to remove pigments. The bleaching process involves the use of an absorbent, such as Fuller’s earth, which will also remove some minor residual impurities, such as soaps that may not have been removed in the neutralization step, chelated metals, and peroxides, that are the source of off flavors. The bleaching process is usually done under vacuum and is a continuous process.  DEODORIZATION it is usually the last step in the refining process. Thus, it is done after any optional processing step. Fats are excellent solvents for most flavor compounds, and many fats contain a variety of volatile chemicals that are odor active and thus impart a smell and flavor to the fat. In addition, several of the flavor volatiles are secondary products of fat oxidation and impart a rancid quality to the oil.  The deodorization process is essentially a steam distillation under vacuum and is based on the large difference in vapor pressure between the triacylglycerides and the volatile impurities. The vacuum lowers the boiling point and increases the vapor pressure of the various volatile components even further; the steam aids in the evaporation of the volatiles because it can come into intimate contact with the fat, allowing the volatiles to be “carried out” of the fat. OPTIONAL PROCESSING STEPS DEWAXING Waxes are esters of long-chain free fatty acids and monohydroxyl alcohols. Most waxes have a high melting point, causing turbidity of a liquid fat over time. Waxes rarely influence the overall functionality of the fats and are removed by slightly chilling the fat. Because of their high melting point, waxes will crystallize out before the triacylglycerides do and can be filtered out HYDROGENATION Hydrogenation is probably the most commonly used optional processing step. The purpose of hydrogenation is the saturation of fats, which is the addition of hydrogens to the double bonds in the fats. Hydrogenation will increase the melting point of a triacylglyceride. Hydrogenation lowers the degree of unsaturation, which makes the fat more resistant to oxidation. A classical example is the partial hydrogenation of soybean oil. Soybean oil contains small amounts of linolenic acid (C18:3), which are responsible for flavor reversion (off flavor development). Partial hydrogenation of the oil eliminates the linolenic acid, resulting in a much more stable fat.  Because of the differences in reaction rates, highly unsaturated fatty acids are hydrogenated quicker than fatty acids with fewer double bonds. In hydrogenation, the fat is mixed with hydrogen gas and a catalyst. The most commonly used catalyst is nickel. Hydrogenation is usually done in a closed vessel at high temperatures and pressures. A problem with hydrogenation that has recently gained considerable attention is the development of trans fatty acids.  INTERESTERIFICATION It is a process that rearranges the fatty acids of a fat product, typically a mixture of triglycerides. The process implies breaking and reforming the ester bonds C–O–C that connect the fatty acid chains to the glycerol hubs of the fat molecules. Although interesterification can dramatically change the functionality of a fat, it is not commonly practiced because of a lack of control over the resulting fat.  INTERESTERIFICATION Unlike hydrogenation or interesterification does not change the overall fatty acid profile of the fat; it rearranges the fatty acids within and among triacylglycerides by hydrolyzing and reesterifying ester bonds between the fatty acids and the glycerol molecules. The result is a fat with a narrower melting range due to more random distribution of fatty acids among the triacylglycerides. WINTERIZING /FRACTIONATION The term fractionation is divided fat into fractions. Fractionation is based on the differences in melting point among the various triacylglycerides. Because the fractionation of the fat is based on temperatures well below room temperature, the process has also been termed winterizing. In winterizing, the temperature of the fat is lowered, which causes triacylglycerides with a high melting point to crystallize, that is, solidify. Triacylglycerides with high melting points contain a relatively larger share of either saturated fatty acids or trans fatty acids.  Winterization can be used to reduce the amount of trans fatty acids that were formed during hydrogenation, although there is no selectivity for trans fatty acids. The effect of winterizing can be easily modeled in a home setting by placing olive oil in a refrigerator. The commercial process often involves “seeding” the liquid fat (oil) with a solid fat, allowing for faster crystallization. The fat is then chilled via cooling coils at a specific rate that depends on the type of fat. The chill rate and agitation rate are crucial for proper crystallization. The solid, crystallized fat is then separated from the liquid fraction by means of filtration. PLASTICIZING/TEMPERING While the fractionation process is used to create a fat that remains a liquid (oil) at refrigeration temperatures, the plasticizing or tempering process is used to give a fat that is solid at room temperature a certain functionality. In the plasticizing process a fat that is mostly solid at room temperature is heated well above its melting range. The rate of cooling it back down to room temperature and the degree of agitation will direct the crystallization, influencing not only the crystal size, but also, more importantly, the crystal type, which is of great importance in the manufacturing of foods containing solid fats such as chocolate products. FINISHED PRODUCT The product of fat refining is a 99.9% pure mixture of triacylglycerides that has a bland flavor and a free fatty acid content ≤ 0.05%. The peroxide value, a measure of the degree of oxidation, is ≤ 0.2. The color depends on the origin of the fat, but is usually a 2.0–3.0 on the red Lovibond color scale, which is equal to a light yellow.  Tomato Processing Food processing Dr. Mohammed Alsebaeai Assistance Professor (Ph. D) in Food science Lebanese International University  Vegetables: Tomato Processing BACKGROUND INFORMATION The composition of the tomato is affected by the variety, state of ripeness, year, climactic growing conditions, light, temperature, soil, fertilization, and irrigation. Tomato total solids vary from 5 to 10%, with 6% being average. Approximately half of the solids are reducing sugars, with slightly more fructose than glucose.  Vegetables: Tomato Processing BACKGROUND INFORMATION A quarter of the total solids consist of citric, malic and dicarboxylic amino acids, lipids, and minerals. The remaining quarter, which can be separated as alcohol- insoluble solids, contains proteins, pectic substances, cellulose, and hemicellulose.  Tomatoes are mostly water (94%), a disadvantage when condensing the product to paste. They are a reasonably good source of vitamin C and A. In 1972 tomatoes provided 12.2% of the recommended daily allowance of vitamin C, and only oranges and potatoes contribute more to the American diet. Tomatoes provided 9.5% of the vitamin A, second only to carrots.  A review of epidemiological studies found that evidence for tomato products was strongest for the prevention of prostate, lung, and stomach cancer, with possible prevention of pancreatic, colon and rectal, esophageal, oral cavity, breast, and cervical cancer. Tomato juice and paste have more bioavailable (absorbed into the blood) lycopene than fresh tomatoes when both are consumed with corn oil. This may be because thermally induced rupture of cell walls and weakening of lycopene-protein complexes releases the lycopene, or because of improved extraction of lycopene into the lipophilic corn oil.  Fresh tomatoes are the fifth most popular vegetable consumed in the United States (16.6 pounds per capita), after potatoes (48.8), lettuce (23.3), onions (17.9), and watermelon (17.4). Canned tomatoes are the most popular canned vegetable, at 74.2 pounds per capita in the United States. In the condiment category, salsa and ketchup are number one and two, respectively. RAW MATERIALS PREPARATION The flowchart for processing tomatoes into juice, paste, whole, sliced, or diced tomatoes is shown in the figure shown in the next slide. After harvesting, tomatoes are transported to the processing plant as soon as possible. Once at the plant, they should be processed immediately, or at least stored in the shade. Fruit quality deteriorates rapidly while waiting to be processed. GRADING The first step the tomatoes go through is grading, to determine the price paid to the farmer. Individual companies may set their own grading standards. Grading is done on the basis of color and percentage of defects.  Color can be determined visually by estimation of what percentage of the surface is red, or with an electronic colorimeter on a composite raw juice sample. Defects include worms, worm damage, freeze damage, stems, mechanical damage, mold, and decay. Tomatoes for canning whole, sliced, or diced are graded on the basis of color, firmness, defects, and size. Graders must be trained to evaluate and score color and firmness. Color should be a uniform red across the entire surface of the tomato.  Firmness, or character, is important to be sure the tomato will survive canning. Soft, watery cultivars or cultivars possessing large seed cavities give an unattractive appearance and therefore receive a lower grade. Size is not a grading characteristic They inspect fruit for color, soluble solids, and damage (California Department of Food and Agriculture 2001). WASHING Washing is a critical control step in producing tomato products with a low microbial count. A thorough washing removes dirt, mold, insects, Drosophila eggs, and other contaminants. The efficiency of the washing process will determine microbial counts in the final product. Several methods can be used to increase the efficiency of the washing step. Agitation increases the efficiency of soil removal.  Surfactants may be added to the water to improve the efficiency of dirt removal; The washing step also serves to cool the fruit. Flume water may be either recirculated or used in a counterflow system, so that the final rinse is with fresh water, while the initial wash is done with used water.  Chlorine is frequently added to the water. Chlorine will not significantly reduce spores on the tomato itself because the residence time is too short. However, chlorine is effective at keeping down the number of spores present in the flume water. SORTING ‫الفرز‬ The first sorter, especially in small plants, is an inclined belt. The tomatoes are off-loaded onto the belt. Photoelectric color sorters are used in almost every plant to remove the green and pink tomatoes. A small percentage of green tomatoes in tomato juice does not adversely affect the quality. Green tomatoes bring down the pH, but do not affect the color of the final product. In addition, less mature tomatoes result in a higher viscosity paste. Pink or breaker tomatoes are a problem, however, because they decrease the redness of the juice. Both pink and green tomatoes need to be removed from the whole peel or dice line. CORING AND TRIMMING In the past, tomatoes were cored by machine or, more frequently, by hand, to remove the stem scar. Modern tomato varieties have been bred with very small cores so that this step is no longer needed. Trimming to remove rot or green portions is not practiced in the United States due to the high cost of labor. JUICE, PASTE, AND SAUCE PRODUCTION The majority of processed tomatoes are made into juice, which is condensed into paste. The paste is remanufactured into a wide variety of sauce products. BREAK The tomatoes are put through a break system to be chopped. Some break systems operate under vacuum to minimize oxidation. When vacuum is not used, the higher the break temperature, the greater the loss of ascorbic acid. Tomatoes can be processed into juice by either a hot break or cold break method. Most juice is made by hot break.  Inactivation enzymes helps to maintain the maximum viscosity. Most hot break processes occur at 93–99°C. In the cold break process, tomatoes are chopped and then mildly heated to accelerate enzymatic activity and increase yield. Pectolytic enzyme activity is at a maximum at 60–66°C. Cold break juice has less destruction of color and flavor but also has a lower viscosity because of the activity of the enzymes. EXTRACTION After the break system, the comminuted tomatoes are put through an extractor, pulper, or finisher to remove the seeds and skins. Air incorporation during extraction should be minimized because it oxidizes both lycopene and ascorbic acid.  Inside of a screw-type tomato extractor. DEAERATION Deaeration to remove dissolved air incorporated during breaking or extraction is frequently the next step. The juice is deaerated by pulling a vacuum as soon as possible, because oxidation occurs rapidly at high temperatures. Deaeration also prevents foaming during concentration. If the product is not deaerated, substantial loss of vitamin C will occur. HOMOGENIZATION The juice is homogenized to increase product viscosity and minimize serum separation. The homogenizer is similar to that used for milk and other dairy products. CONCENTRATION INTO PASTE If the final product is not juice, the juice is next concentrated to paste. Concentration occurs in forced circulation, multiple effect, vacuum evaporators.  The paste is concentrated to a final solids content of at least 24% NTSS (natural tomato soluble solids) to meet the USDA definition of paste. ASEPTIC PROCESSING The paste is heated in a tube-in-tube or scraped surface heat exchanger, held for a few minutes to pasteurize the product, then cooled and filled into sterile containers, in an aseptic filler. A typical process might heat to 109°C, then hold 2.25 minutes, or heat to 96°C and hold for 3 minutes. REMANUFACTURING INTO SAUCE Manufacturers of convenience meals buy tomato paste and remanufacture it by mixing it with water, particulates, and spices to create the desired sauce. Some sauce is made directly from fresh tomatoes during the tomato season, but this is less common. Sauce production from paste is more economical because it can be done during the off season using the equipment in tomato processing plants that would otherwise be unused. It is also cheaper to ship paste than sauce.