Food Science Reviewer PDF

INTRODUCTION TO FOOD SCIENCE  Introduction of many more varieties of food WHAT IS FOOD?  Cross breeding Anything people eat to provide n...

INTRODUCTION TO FOOD SCIENCE  Introduction of many more varieties of food WHAT IS FOOD?  Cross breeding Anything people eat to provide nourishment Genetically Modified Organisms (GMO) Anything taken into the body by mouth which includes drinks, bubble gum, any  Organisms, mostly crops where the genetic make up had been altered for quality, substance or any ingredient needed in the preparation of food. yield or resistance to diseases (genetic manipulation). Criteria for an item to be considered as food:  Biotechnology Safe Effects of biotechnology in food supply: Provide nutrients 1. Modification of food components to provide new and/or improved functional Provide pleasurable experience during consumption properties Satisfy hunger  Biomodification of milk fat in butter-making to unsaturated the fat resulting in Affordable healthier higher polyunsaturated fatty acids and improved spreadability of butter. A food item that is beyond one’s ability to acquire, whether by purchase or by 2. New processes for the production of foods and food components personally gathering it, can certainly not be considered as one’s food, no matter how  Use of plant cell cultures for production of new flavors. desirable.  Removal of naturally occurring toxins or undesirable characteristics in plants. FOOD SELECTION AND FOOD CHOICES  Euricic acid (rapeseed) Food Selection  Caffeine (coffee) Determined by the available food materials in the locality  determined by geography, soil, climate, production technology, transport THE SCIENCE OF FOOD & INTERRELATIONSHIP WITH OTHER SCIENCES system, storage and preservation facilities, and the economic condition of the community. Nutrition and biochemistry Food Choices Conserve the naturally occurring nutrients in food so these essential nutrients would still Refined by cultural attitudes and religious beliefs be in the food after cooking. HISTORY OF FOOD AND CIVILIZATION As far back as 1.75 million years ago Microbiology  Early humans were regularly eating animals and plants. Improved traditional food preservation methods  Share food with the whole tribe. Made food safer Integral part of early man’s diet  animals such as rats, mice, frogs, snakes, tortoise and antelopes HACCP (Hazard Analysis Critical Control Point) Ensured the safety of food prepared in commercial kitchens, institutional kitchens and  Peking man, Neanderthals, Homo erectus food processing establishments.  cook their own food  Discovery of Fire Food Science Enabled man to cook food Study of physical, chemical, microbiological and sensory aspects of food and the  Make food digestible transformation that food undergo as reflected by changes in characteristics and  More sanitary properties from the time food is produced to the time food is consumed.  Better tasting  Production of pottery Applications of Disciplines involved in Food Science and Technology  Associated with the culture and civilization  Glazed pottery (allowed cookery development) Discipline Examples of Food Science and Technology Applications  Food could be boiled in a liquid Biology, Cell Understanding of postharvest plant physiology, food quality, plant disease  Food could be baked Biology control, and microbial physiology; food safety  Fruits and grains could be fermented Biotechnolog Rice with increased content of beta-carotene (vitamin A precursor);  Age of exploration y enzymes for cheesemaking, breadmaking, and fruit juice manufacture  Made possible for distribution of produce from various regions of the world. Chemistry Food analysis, essential for implementing many of the applications listed  Philippines – key transshipment point of crops. here; improved food quality; extended shelf life; development of functional  Mexico – corn and cacao foods (foods and food components providing health benefits beyond basic  South America – tomato and peanuts nutrition)  Green Revolution of 1960’s Computer Food manufacturing process control, data analysis Introduced methods of increasing production Science  Improving inputs (fertilizers and pesticides) Genomics Understanding of plant and animal characteristics; improved control of  desirable attributes; rapid detection and identification of pathogens FOOD, LIFE, AND HEALTH Materials Effective packaging; understanding of how materials properties of foods Science provide structure for texture, flavor, and nutrient release 1. Survival Hierarchy Microbiology Understanding of the nature of bacteria (beneficial, spoilage, and disease- 2. Hunger and Satisfaction causing microorganisms), parasites, fungi, and viruses, and developments 3. No adverse effect on health and advances in their detection, identification, quantification, and controi 4. Health and maintenance (for example, safe thermal processes for commercial sterilization); 5. Promotes better health and reduce the risk of disease hygiene; food safety 6. Food and medicine have common origin Nutrition Foods fortified with vitamins and minerals for health maintenance: functional foods for addressing specific health needs of certain Food Definition (Nutritional sense) subpopulations; development of diets that match human nutrient Anything which when taken into the body will perform one or more of the functions: requirements; enhanced health and wellness  Build and repair tissues Physics, Efficient food manufacturing processes to preserve food attributes and  Provide energy Engineering ensure food safety; pollution control; environmental protection; waste  Regulate body processes reduction efforts Main nutrients in food Sensory Understanding of chemosenses (for example, taste and odor) to meet  Water Science different flavor needs and preferences  Proteins Toxicology Assessment of the safety of chemical and microbiological food  Carbohydrates components, food additives  Fats  Minerals CLASSIFICATION AND KINDS OF FOOD According to source Nutrients for building and Nutrients providing Nutrients for regulating Plant repair of tissues Energy body Grains/cereals, pulses/dried legumes, fruits, vegetables, tubers, nuts, fungi, oilseeds, processes seaweed, etc. Proteins Carbohydrates Minerals Animal Vitamins and minerals Fats Vitamins muscles/meat, entrails, milk, poultry, eggs, fish, shellfish, etc. Water Proteins Minerals Water Protein (enzymes) (phosphates) According to level of manufacturing method involved Primary processed Nutritional Guidelines for Filipinos Derived basic commodities from operations as milling, oil extraction or animal slaughter A set of primary recommendations to promote good health through proper nutrition. (milled rice, pork, fish) Seeks to foster an adequate and balanced diet as well as desirable food and nutrition Preserved practices and healthy habits suitable for general population. Still retain the natural form but are treated to lengthen shelf life. (canned goods, hams) 1. Eat a variety of foods every day. Manufactured 2. Breastfeed infants exclusively from birth to 6 months, and then, give appropriate foods Bears little or no resemblance to the physical form of the original food source. (fish while continuing breastfeeding. balls, rice wines) 3. Maintain children’s normal growth through proper diet and monitor their growth regularly. According to location 4. Consume fish, lean meat, poultry or dried beans. Mediterranean, European, Italian, French, African, Asian, Indian, Chinese, Mexican, 5. Eat more vegetables, fruits and root crops. Filipino, etc. According to psycho-socio-cultural CHEMICAL COMPOSITION OF FOODS Comfort food, ethnic foods, traditional foods, healthy foods (low carb, vegetarian, FOOD COMPOSITION lactose-free, etc.) Macromolecules/ Macronutrients Others  Nutrients that are required by the body in large quantities Designer foods Micromolecules/ Micronutrients Functional foods  Nutrients required by the body in smaller quantities Nutraceuticals  Non-nutritional Components Probiotics  organic constituents of food having no nutritional function but some exert protective Prebiotics or disease-preventing effects.  MACROMOLECULES/MACRONUTRIENTS 2. LIPIDS/FATS  Also used in the body for the purpose of energy storage 1. CARBOHYDRATES  Fats (Solid/Semisolid at room temperature) and oils (liquid at room temperature)  Carbon, Hydrogen, Oxygen  Taste, aroma, and texture of food  Major contributor of energy intake in the body  Fats and oils are both esters glycerol and monocarboxylic acids (fatty acids).  Roles in plants:  Edible fats are complex mixtures of triglycerides and small amounts of other As storage for energy substances occurring naturally or are derived through processing and storage of fat. As structural framework  Saturated fatty acids – all of the electrons in the carbon atoms of the fatty acid chain  Roles in animals: are paired off or saturated. As storage for energy and are found in the milk, blood and tissues of animals; glycogen Most common saturated fatty acids found in animal fats in the liver and muscle. Palmitic acid (C15H31COOH)  Function in food formulations: Stearic acid (C17H35COOH) Sweetener, thickener, stabilizers and fat replacers in various food formulations  Unsaturated fatty acid – at least one of the carbons in the fatty acid chains has an  Fiber is responsible for removing some toxic substances in the body and helps unpaired electron. maintain healthy gut, thus playing a significant role in preventing color cancer. Omega-3 and Omega-6 (Essential Fatty Acids that need to be included in the diet  Other kinds affect the kind of bacteria that will predominate in the intestines. because the human metabolism cannot create them from other fatty acids. CLASSIFICATION OF CARBOHYDRATES TYPES OF LIPIDS/FATS 1. Monosaccharides (1 sugar) – Glucose, fructose 1. Simple lipids - esters of fatty acids with various alcohols 2. Disaccharides (2 sugars) – Sucrose (Table sugar), lactose Fats: Esters of fatty acids with glycerol. Oils are fats in the liquid state 3. Oligosaccharides (3 to 10 sugar molecules) – Raffinose and stachyose Waxes: Esters of fatty acids with higher molecular weight monohydric alcohols 4. Polysaccharides (more than 10 sugar molecules)– Starch, cellulose, pectin 2. Complex lipids - esters of fatty acids containing groups in addition to alcohol and fatty acid MACROMOLECULES/MACRONUTRIENTS Phospholipids: lipids containing, in addition to fatty acids and alcohol, phosphate group. The Carbohydrates: Food Sources and Function They frequently have nitrogen-containing bases and other substituents, eg, in Carbohydrates Food Sources Function in food glycerophospholipids the alcohol is glycerol and in sphingophospholipids the alcohol is Glucose Fruits Sweetener, energy source sphingosine. Fructose Fruits Sweetener, energy source Glycolipids (glycosphingolipids): Lipids containing a fatty acid, sphingosine and Sucrose Fruits cane and beet Sweetener, energy source carbohydrate. Starch Cereals, tubers Bulk, energy source Other complex lipids: Lipids such as sulfolipids and amino lipids. Lipoproteins may also Cellulose Cereals, tubers Bulk, source of dietary fiber be placed in this category. Pectin Fruits Jelly, thickener, dietary fiber Gum Plant, bacterial action Thickener, emulsifier 3. Derived lipids These include fatty acids, glycerol, steroids, other alcohols, fatty aldehydes, and ketone bodies, hydrocarbons, lipid-soluble vitamins, and hormones. Because they are The Polysaccharides, Digestibility and Food Sources uncharged, acylglycerols (glycerides), cholesterol, and cholesteryl esters are termed Polysaccharide Digestibility Food Sources neutral lipids. These compounds are produced by the hydrolysis of simple and complex Starch Digestible Cereals, Tubers and their products lipids. Dextrin Digestible Browned starch as in toasted bread and PROCESSES partially hydrolyzed starches, honey 1. Hydrogenation Glycogen Digestible Browned starch as in toasted bread and Industrial process making use of metal catalysts. partially hydrolyzed starches, honey Addition of one hydrogen atom to saturate the carbon atom. Galactogens Partially digestible Vegetables, gums, agar Unsaturated fatty acids, oliec, linoliec and linolenic becomes stearic acid, a saturated Inulin Partially digestible Vegetables bulbs like onions and garlic, fatty acids. artichoke gums Mannosans Partially digestible Legumes 2. Trans Fatty Acid Pentosans Partially digestible Fruits, gums Increases low density lipoproteins (LDL or bad cholesterol) and decreases high density Cellulose Indigestible Fruit skins, seed coverings, vegetable stalks lipoproteins (HDL or good cholesterol) which can lead to coronary heart disease (CHD). Hemicellulose Indigestible Fruits, vegetables Lignin Indigestible Woody tissues 3. PROTEINS  Nitrogen, Carbon, Hydrogen, and Oxygen (Sulfur and Phosporus)   Amino Acids (Essential and Non-essential) PHYSICAL REACTIONS IN FOOD  Meat (meat, fish, etc.) and vegetable (legumes, cereals, etc.) FOOD DISPERSION  Development and maintenance of body tissues and Hard Solids  muscles Soft Solids  Browning (Maillard Reaction) and texture food. Liquids Commercial food such as baby foods, mayonnaise, and plant food concentrates AMINO ACIDS (orange, tomato, apple, etc) are concentrated dispersions of solid (suspensions) or NON ESSENTIAL fluid (emulsions) matter in fluid media, which may behave as soft solids Alanine Mixture produced by scattering one material in another. Arginine Glycine Description of a dispersed system in food Asparagine Ornithine  A dispersed system is kinetically stable mixture of one phase (solid, liquid, Aspartate Proline gas) in another largely immiscible phase Cystine  It will separate into its components with different densities due to gravity , but Glutamic Serine only very slowly (e.g oil and vinegar mixture) Tyrosine Classification according to the size of the dispersed phase  True Solution ESSENTIAL  Colloidal Dispersion Histidine Phenylalanine  Suspension Isoleucine Table 3-1. Three Kinds of Dispersions Leucine Threonine True solutions Colloidal Dispersions Suspensions Lysine Tryptophan Dispersed phase in ionic or Dispersed phase in colloidal Dispersed phase in Methionine molecular subdivisions subdivision mechanical subdivision Valine Particles are not visible with Refracted light of particles Particles visible with low- ultra-microscope visible with ultra-microscope magnification microscope or Proteins and Their Classification in Different Foods even by naked eye Protein Sources Size of particles less than Particle size between Inm to Particle size much greater Simple Proteins Sources Egg white, lactalbumin, legumetin of peas, leucosin 1mu 0.5mm than Albumins of wheat Serum globulin, myosin in muscle, edestin in 0.5mm Globulins wheat, ovoglobulin in egg yolk Formation of gels is not Gel formation is Gel formation not Glutelins Glutenin in wheat, oryzenin in rice Gliadin in wheat and rye, characteristic characteristic characteristic Prolamines zein in corn, hordein in barley Collagen and keratin from Transparent Transparent to translucent Generally opaque dispersed Scleroproteins connective tissues, bones, hair, hom, etc. Histones from calf phase Histones thymus and pancreas Protamines of the sperm of fish Particles pass through Particles pass through filter Particles do not pass Protamines parchment membrane paper but not through through filter paper Conjugated Proteins Ribonucleoprotein in cell cytoplasm, Deoxyribonucleoprotein parchment Nucleoproteins in chromosomes Ovomucoid in egg white, osseomucoid in Intense kinetic movement Less kinetic movement, Little movement Mucoproteins bones Lecithin, cholesterol and other lipoproteins in various more Brownian movement Lipoproteins tissues Conjugates of protein-carbohydrate in various System show high osmotic System exhibit less osmotic System exhibit insignificant Glycoproteins tissues Hemoglobin, flavoproteins, chlorophyll, heme, pressure pressure osmotic pressure Chromoproteins ferretin Casein in milk and ovovitellin in egg yolk Food example: brine, syrup, Food examples: sauces and Raw starch in water, Phosphoproteins Hemoglobin and hemocuprein carbonated beverage, gravies, chocolate drink, chopped pickles in vinegar. Metalloproteins ready- to-drink coffee gelatin, mayonnaise Derived Proteins Coagulated blood Coagulated milk Intermediate products of Primary Derivatives protein hydrolysis SOLUTIONS Fibrin , Casein Homogeneous mixture of the molecules or ions of two different substances, one of Secondary Derivatives, which is usually water. Proteoses, peptones, Solute – dissolved substances; small particles with much kinetic energy that they can peptide squeeze themselves between water molecules.  Solute may be in ionic form – table salt (Na+ and Cl-) or molecular form such as A. Sol sugar A liquid gel. A solution becomes saturated when the solvent can no longer dissolve additional Gelatin or gums dissolved in hot water increment of the solute, so that the concentration remains the same no matter how B. Gel much additional solute is added Phases in the dispersions have strong interactive attraction so that the whole system Saturation point of salt solution is 25% salt and for sugar is 65%. develops a rigid network structure. A state of super saturation is achieved when a saturated solution is prepared at  Gel point - A point in the sol-gel transformation when the liquid begins to take a elevated temperature then cooled without agitation semisolid character. Colligative Properties  Both protein and starch can be used in the formation of sol or gel Vapor pressure Pressure exerted by the gas above the liquid when equilibrium exists such as when Sol and Gels evaporation and condensation occur at the same rate. When a jelly is made, gelatin is dispersed into a liquid and heated to form a sol. As the sol Increases with increasing temperature cools, protein molecules unwind forming a network that traps the water and forms a gel Decreases with the addition of non-volatile solute. If corn starch is mixed with water and heated, the starch granules absorb water until they Boiling point rupture, the starch then disperses in the water and the mixture becomes more viscous and The temperature at which vapor pressure equals the external pressure, which is the forms a gel on cooling atmospheric pressure at ordinary conditions. C. Emulsions The greater the reduction in vapor pressure due to non-volatile solutes, the higher the Mixtures of at least two immiscible liquids (oil and water). temperature required to raise the vapor pressure sufficiently to permit boiling. A stable emulsion is formed when two immiscible liquids are held stable by a third One mole of non volatile non-ionizing solute will raise the boiling point of one liter of substance, called an emulsifying agent. water by 0.52ºC; but one mole of sodium chloride will raise the boiling temperature of Two phases one liter of water by 1.04ºC instead of 0.52ºC Dispersed/discontinuous/internal phase Volatile substances increases vapor pressure thus has the opposite effect that of Liquid that is dispersed as droplets. lowering the boiling point. Continuous or external phase Freezing point Surrounding liquid. Solutes depress the freezing point. General Types of Emulsions 1 mole of sugar in a liter of water lowers the freezing point at -1.86 ºC. *Emulsions also include non liquids in the definition, such as breads, meat emulsions, and Osmotic pressure ice cream. Osmosis is the passage of water through semi-permeable membrane that separates two solution of varying concentrations of solute. Example: osmotic drying of mangoes COLLOIDAL DISPERSION Stability of emulsion is determined by: Colloids are two-phased systems in which the particles in the discontinuous phase are 1. Viscosity of the continuous phase between 1 nanometer and 0.5 millimeter. 2. Presence of emulsifying agent and its concentration Of nine possible colloidal systems, only five has applications in foods: 3. Size of the droplets a) Sol 4. Ratio dispersed phase to continuous phase b) Gel c) Emulsion D. Foam d) Foam Dispersion of gas (air or carbon dioxide) in either liquid or solid. e) Liquid foam Examples   Carbonated drinks (soda) Mechanism of Heat Transfer  Brewed or fermented alcoholic beverages 1. Conduction Aeration – process of adding air into a food or beverage system such as in beating egg Thermal energy is transferred from one molecule to an adjacent molecule without any whites. change in relative positions of the molecules. Foam consist of tiny pockets of gas surrounded by a thin film of water that has various The only molecular movement occurring is oscillation within a fixed point substances dissolved in it. Area involved in the heat transfer, temperature difference per unit thickness, and the Dissolved substances are the key to foam, as pure liquid cannot foam, no matter how thermal conductivity of material affects the rate of heat transfer by conduction much it is agitated. 2. Convection Foams form as a result of rapid diffusion of protein to the air-water interface, which Restricted to liquids and gases where molecules are free to move about resulting in the reduces the surface tension, necessary for foam formation. The protein then partially mixing of hot molecules and cold molecules unfolds, which encapsulates air bubbles and creates the association of protein Faster than conduction. molecules leading to an intermolecular cohesive film with a certain degree of elasticity Other Physical Properties of Colloidal Suspensions Dispersed Dispersing medium/ Common Food Examples Surface tension Phase Continuous Phase Name  Tendency of liquids to assume the least possible surface area, which is the reason why Solid Liquid Sol Gelatin in hot water, drops are spherical in shape. dilute starch in hot  Surface tension decreases with increase of temperature water  Group of substances that lower the surface tension - aldehydes, fatty acids, amines, Liquid Solid Gel Jelly, carrageenan gel, alcohols, tannins, saponins, and proteins. custard, gelatin mold  Sugar increases the surface tension of water Liquid Liquid Emulsion Mayonnaise, salad Viscosity dressing, cream soup  Resistance of a liquid or semisolid material to flow; ratio of shear stress to shear rate. Gas Solid Foam Marshmallow, whipped  Measured in centipoise which is the viscosity of water at 20ºC butter  Consistency – usually measured as the time of flow through standard equipment Gas Liquid Liquid Foam Egg foam, soda water, usually a tube such as a viscometer, a consistometer or even improvised equipment sponge cake Factors that Affect Viscosity As the liquid/gas is heated, initially by conduction, the molecules which are heated first Temperature becomes less dense and rises to the top while the still colder molecules moves to the Concentration of dispersed phase bottom.  The greater the concentration of dispersed phase, the more viscous the more As another layer of molecules are heated the less dense portion rises creating viscous the dispersion. convection current. Molecular characteristics Natural or free convection and forces convection  Hydrocolloids like gums and carrageenan, significantly affect viscosity. Area involved in heat transfer, temperature difference between hot and cold portion of Degree of dispersion the gas/liquid, and heat transfer coefficient  Finer dispersion are more viscous than coarser ones. 3.. Radiation An electromagnetic mechanism. HEAT TRANSFER Electromagnetic waves are not converted to heat unless it collides with matter. Heat is a form of energy caused by the vibratory or kinetic movement of molecules. Upon collision, radiation can be absorbed, reflected or transmitted. Heat transfer is an energy transfer process. The absorbed energy can be manifested as heat. Kinetic energy of molecules increases when heat energy is absorbed. Electromagnetic radiation travels at the speed of light and is characterized by Heat is transferred when fast-moving molecules collides with the slow-moving wavelength and frequency. molecules causing the fast-moving molecule to lose kinetic energy while the slow- Wavelengths that can be readily absorbed, thus converted to heat are in the infrared moving molecules is manifested by its temperature region (0.8 to 100 millimicron). Infrared radiation is transferred only to the surface so only the surface gets heated by Heat transfer involves two things: radiation; heating of the interior is by conduction. Temperature – amount of thermal energy available. Microwave heating Heat flow – movement of thermal energy from place to place.  Electromagnetic radiation is generated in special oscillator tubes called Thermal energy - related to the kinetic energy of molecules. magnetrons that are radiated in a close chamber containing the food to be heated. The higher the material’s temperature, the greater the thermal agitation of its  The walls of the chamber are highly reflective, so radiation bounces back and forth constituent molecules indicated by both linear and vibrational modes. until it is absorbed by the food. A difference in temperature is necessary for heat transfer to take place   As the microwaves are absorbed by the water/oil in the food, the molecules vibrate  Disaccharides: composed of two monosaccharide units rapidly as molecules align with the rapidly changing microwave field.  These vibrations, creates friction that produces heat within the food.  Sucrose  On hydrolysis, yields one molecule of glucose and one molecule of fructose 4. Induction Heating  Lactose Heat is actually “induced” within the part itself by circulating electrical currents.  Milk sugar Relies on the unique characteristics of radio frequency energy – that portion of the  On hydrolysis, yields one molecule glucose and one molecule galactose. electromagnetic spectrum below infrared and microwave energy.  Maltose Since heat is transferred to the product via electromagnetic waves, the part never  Malt sugar comes into direct contact with any flame, the inductor itself does not get hot.  From grains and starch Induction heater consists of an electromagnet through which a high frequency  Yields 2 glucose units alternating current is passed. Market Forms Frequency of the alternating current used depends on the size of the object, the type Market Forms Description of material used, the coupling between the coil, and the object to be heated and Granulated  Refined sugar the depth of penetration  Fineness and whiteness depend on degree of refinement How induction cooking works: Brown sugar  Partially purified 1. The current’s electronics power a coil that produces a high-frequency electromagnetic  Light brown to very dark brown field. 2. That field penetrates the metal of the ferrous/magnetic material cooking vessel and sets Raw brown sugar  Unrefined up a circulating electric current, which generates heat.  Muscovado or kinugay 3. The heat generated in the cooking vessel is transferred to the vessel’s content Panutsa  Sugar cane extract evaporated to brown syrupy 4. Nothing outside the vessel is affected by the field—as soon as the vessel is removed concentrate then poured in to coconut halves and from the element, or the element is turned off, heat generation stops. allowed to dry to a solid, brown concave mass called sinakob or panutsa. Sugar Cookery Powdered or  "extra fine" Sugar: General term for monosaccharides and disaccharides in crystalline form; confectioner's sugar  Mixed with cornstarch to prevent caking  Sweet  Soluble Syrups  Organic compounds; - Liquid sugars containing varying amounts of water. Unless qualified, refers to sucrose, also known as “table sugar” that commonly comes from Cane syrup sugar cane or sugar beets (contains 99.9% sucrose). - Obtained by concentrating and heat treatment of sugar cane juice - Contains all the natural soluble materials in the juice Types according to source Maple syrup  Cane – most common - Obtained from sap of maple tree  Maple – has distinct “maple” flavor and color - Contains 64-68% sucrose, glucose and fructose, the rest is water.  Beet Corn syrup  Corn hydrolysis - Cerelose - Obtained by hydrolysing cornstarch containing 30% dextrins, 32% maltose and Types according to chemical form 18% glucose; less sweet.  Monosaccharides: simplest sugars (C6H12O6) - Dark when combined with refiner’s syrup, or light when decolorized.  Glucose or dextrose or grape sugar - High fructose corn syrup (HFCS)  Hydrolyzed from maltose, lactose or sucrose  Obtained by converting most of the glucose in corn syrup to fructose.  Present in animal tissues as blood glucose Refiner’s syrup  Fructose or levulose or fruit sugar - Liquor that remains after crystallization of sucrose  Known as fruit sugar - Has 25% water and has the characteristic flavour of brown sugar.  Does not crystallize readily Honey  Sweetest among all sugars - Produced by bees from nectar of flowers and stored in honey cells  Galactose - Flavor depends upon source of nectar  Not found naturally in food except as a component of lactose or milk sugar - Contains about 35% glucose, 40% fructose, 5% sucrose and 20% water - Contains traces of minerals  Physical and Chemical Properties  Browning of sugar/sugar solutions when heated above melting point at 210 C or Sweetness 410 F causing the removal of water from glucose and fructose producing caramel  Fructose – sweetest (non-crystalline product)  Lactose – least sweet  Melting point of sugar – 186 C or 367 F Solubility Fermentation  Inversely related to crystallization  Glucose is highly fermentable by yeast but not lactose.  Directly related to hygroscopicity and intensity of sweetness Creaming  Factors affecting solubility  Ability to incorporate air within crystals when beaten (“creamed”) with plastic fat.  Nature of sugar (solute)  Raises boiling point and lowers freezing point of liquids.  Solubility from most to least soluble: fructose, sucrose, glucose,  Effect on microorganisms maltose and lactose.  Small amount – favor growth  Degree of fineness  High concentration – preservative effect  Temperature Functions of Sugar in Food Preparation  Concentration of sugar  Sweetening agent  Agitation  Main ingredient (candies) Crystallization  Volume and structure improver  Formation of crystals from concentrated sugar solutions  Jelly making  Important in candy making  Acts as dehydrating agent  Inversely related to ease of solubility  Facilitates precipitation of pectin to form the gel network  Factors affecting crystallization  Dehydrating effect is also responsible for sugar’s ability to stabilize egg white  Nature of sugar foams.  Fructose – hardest to crystallize  Baking  Lactose – easiest to crystallize  Serves as substrate for fermentation by yeast in producing CO2 in yeast  Nature of solution leavened breads.  Interfering substances  Leavening agent  Agitation  Ability to incorporate air (when beaten or mixed) as when creaming with fat Hygroscopicity producing better volume.  Ability to absorb moisture from air  Peptizing agent  Has a dehydrating effect on microorganisms – useful in food preservation  Prevent gluten from coalescing (together with fat) producing tender, fine-grain  Directly related to sweetness textured baked product. Maillard browning  Tenderizing agent  Produced when sugars are heated with a source or amino acids (milk, flour,  Delays gelatinization (custards, starchy sauces, puddings) pastillas)  Gives desirable color due to caramelization and Maillard browning. Inversion or hydrolysis  Inversion of sugar (in stored fruit cake – more moist product)  Hydrolysis of sucrose in the presence of acid, enzyme invertase or alkalis give  Nutritive quality equal amounts of glucose and fructose (invert sugar)  Simple sugars are readily digested and absorbed for quick energy.  Hastened by high temperatures  Texture effect (due to caramelization)  Preserving agent  Dehydrating effect on microorganisms  Flavoring and Colorant agent  Humectant  Keep product moist and soft due to hygroscopic ability. Undesirable effects due to the properties of sugars  Loss of crispness of cookies and meringues on standing due to absorption of moisture from air.  Melting of candies (fondants – due to inversion of sugar)  Shrinkage, shriveling and even toughening of food cooked in sugar (fruits, beans etc.) due to the dehydrating effect of sugar.  Spontaneous crystallization of syrups with high concentration of sucrose. Caramelization Sugar Cookery  CANDIES firm enough to hold its  Types according to method of production shape  Crystalline candies Soft Crack 270-290 132-143 Forms hard threads in cold Butterscotch,  Made from sugar mixtures which have been allowed to form tiny crystals water taffy through the addition of interfering substances which serve as nuclei or “seed” for crystal formation or through agitation or beating Hard Crack 300-310 149-154 Forms brittle thread in cold Brittles, glace,  Characterized by fine. Smooth texture in candies water toffee  Fondant, fudge, cream candies, sugar flowers, marshmallow  Non-crystalline candies Molten sugar 320 160 Clear viscous liquid Barley sugar  Made from thick syrup that do not flow at room temperature  Crystallization is prevented by ingredients like acids, cream of tartar, corn Caramel 320-348 160-177 Brown viscous liquid Flavor and syrup called interfering agents and vigorous stirring. color for  Taffy (tira-tira), caramel and hard candies confections  Soft-chewable Sugar Alcohols  Soft enough to be broken or cut by finger pressure alone Water soluble and stable in aqueous solution even during prolonged processing but do not  Caramels, fudge, pastillas undergo carbonyl amine browning or caramelization.  Hard-not chewable Sugar Alcohols  Usually sucked rather than chewed (except the brittles types which are crisp and  Xylitol easy to break)  The normal intermediate product of carbohydrate metabolism.  Lollipops, tira-tira, peanut brittles  Occurs naturally in mushrooms, yeasts, seaweeds, vegetables, and fruits, but  Aerated candies generally extracted from wood pulp.  Characterized by sponginess and fluffiness which are derived from ingredients like  Uses eggwhites or synthetic foam  Chewing gums  Marshmallow, nougat  Sorbitol  Jellies, gums and marzipans  Present in various fruits, berries and plants but is produced commercially by  Soft candies with added ingredients to give them distinct characteristics (pectin for hydrogenating glucose. jellies and special type of gums for gums)  Uses  Jelly beans, gum drops  Used in dietetic candies (slowly absorbed in the gastrointestinal tract) Factors to consider in candy making  As humectant  Type of sugar and solubility  Impairs mold growth by lowering water activity.  Sucrose is most commonly used.  Mannitol  Temperature of cooking and concentration of sugar  Derived from glucose by hydrogenation  Effect of interfering substances  Not hygroscopic  Effect of agitation  Uses  Vigorous stirring prevent crystallization in amorphous or non-crystalline  Bulking agent in powdered foods candies.  Used in chewing gums (low carcinogen content)  Effect of exposure to air Synthetic or Artificial Sweeteners  Produce sticky product – candies absorb moisture from air.  Useful in dietetics as non-calorific sweeteners Sugar Crystals and Confections: Consistency, Boiling Point, and Uses for Syrups  Add sweetness without any energy value (desired in reducing and diebetic diets) Consistency Temperature Range Behavior Uses  Cannot contribute to volume, texture, “body” or viscosity, browning reactions, moistness and tenderness. (°F) (°C) Sweeteners Properties and Applications Current Status Thread 230-236 110-113 Form a 2-inch thread as it Syrup Acesulfame-K  Little or no aftertaste leaves the spoon  Sweetness not perceived immediately Soft Ball 234-240 112-116 Forms in cold water a ball Fondant, fudge,  Not metabolized by the body too soft to retain its shape panocha  Viable for hot and cold beverages, dry mixes, mik products, fruit preparations, Firm Ball 244-250 118-121 Forms in cold water a ball Caramels chewing gums, candies, pharmaceuticals