Food Modification Lecture 6 - Food Additives PDF

Learning Unit 4 Food Modification Lecture 6 - Food Additives Micky Vincent Introduction What gives margarine its pleasing yellow color and prevents salt from becoming lumpy in its shaker? What allows many foods to be available year round, in great quantity and t...

Learning Unit 4 Food Modification Lecture 6 - Food Additives Micky Vincent Introduction What gives margarine its pleasing yellow color and prevents salt from becoming lumpy in its shaker? What allows many foods to be available year round, in great quantity and the best quality? What helps cake batters rise reliably during baking and keeps cured meats safe to eat? What keeps bread mold-free and salad dressings from separating? What improves the nutritional value of biscuits and pasta, and gives gingerbread its distinctive flavor? Food Additives Food Additives – What are Food Additives? In its broadest sense, a food additive is any substance added to food. Legally, the term refers to "any substance the intended use which results or may reasonably be expected to result-directly or indirectly-in its becoming a component or otherwise affecting the characteristics of any food.” This definition includes any substance used in the production, processing, treatment, packaging, transportation or storage of food. Food Additives – What are Food Additives? Additives may be: 1. Natural - Found naturally, such as extracts from beetroot juice (E162), used as a colouring agent. - Natural additives manufactured from natural sources such as soybeans and corn, which provide lecithin to maintain product consistency. 2. Manmade versions - Synthetic identical copies of substances found naturally, such as benzoic acid (E210), used as a preservative 3. Artificial - Other useful additives are not found in nature and must be man-made. - Artificial additives can be produced more economically, with greater purity and more consistent quality than some of their natural counterparts. - Example: Nisin (E234), used as a preservative in some dairy products and in puddings. Food Additives – What are Food Additives? There are TWO TYPES of food additives: 1. Direct additive. - If a substance is added to a food for a specific purpose in that food, it is referred to as a direct additive. - i.e. the low-calorie sweetener aspartame, which is used in beverages, yogurt, puddings, chewing gum and other foods, is considered a direct additive. - Many direct additives are identified on the ingredient label of foods. 2. Indirect food additives. - Indirect food additives are those that become part of the food in trace amounts due to its packaging, storage or other handling. - For instance, minute amounts of packaging substances may find their way into foods during storage. Food Additives – What are Food Additives? Different countries have different regulations and permissible food additives. Currently, there are over 300 permitted additives that can be used in the UK. To regulate these additives, and inform consumers, each additive is assigned a unique number, termed as "E numbers", which is used in Europe for all approved additives. - For example, acetic acid is written as E260 on products sold in Europe, but is simply known as additive 260 in some countries (i.e Australia). The United States Food and Drug Administration listed these items as "Generally recognized as safe" or GRAS. Food Additives – What are Food Additives? Food Additives Why are Additives Used in Foods? 1. To maintain product consistency. 2. To improve or maintain nutritional value. 3. To maintain palatability and wholesomeness. 4. To provide leavening or control acidity/alkalinity. 5. To enhance flavor or impart desired color. Food Additives i. To maintain product consistency. Emulsifiers give products a consistent texture and prevent them from separating. Stabilizers and thickeners give smooth uniform texture. Anti-caking agents help substances such as salt to flow freely. Examples of substances used to maintain product consistency: - Alginates - Lecithin - Mono- & Diglycerides - Methyl Cellulose - Carrageenan - Pectin - Guar Gum - Aluminosilicate Examples of food: - Baked goods, cake mixes, salad dressings, ice cream, process cheese, coconut, table salt Food Additives ii. To improve or maintain nutritional value. Vitamins and minerals are added to many common foods such as milk, flour, cereal and margarine to make up for those likely to be lacking in a person's diet or lost in processing. All products containing added nutrients must be appropriately labeled. Examples of substances used to maintain nutritional value: - Vitamins A and D, Thiamine, Niacin, Riboflavin, Ascorbic Acid, Pyridoxine. - Folic Acid, Calcium Carbonate, Zinc Oxide, Iron. Examples of food: - Flour, Bread, Biscuits, Breakfast Cereals, Pasta, Margarine, Milk, Iodized salt, Gelatin Desserts. Food Additives iii. To maintain palatability and wholesomeness. Preservatives retard product spoilage caused by mold, bacteria, fungi or yeast. Bacterial contamination can cause foodborne illness, including life-threatening botulism. Antioxidants are preservatives that prevent fats and oils in baked goods and other foods from becoming rancid or developing an of flavor. They also prevent cut fresh fruits such as apples from turning brown when exposed to air. Examples of substances used in palatability and wholesomeness of food: - Propionic Acid & its salts, Ascorbic Acid, Butylated Hydroxy anisole (BHA), Butylated Hydroxytoluene (BHT), Benzoates, Sodium Nitrite, Citric Acid. Examples of food: - Bread, Cheese, Crackers, Frozen & Dried Fruit, Margarine, Lard, Potato Chips, Cake Mixes, Meat. Food Additives iv. To provide leavening or control acidity/alkalinity. Leavening agents that release acids when heated can react with baking soda to help cakes, biscuits and other baked goods to rise during baking. Other additives help modify the acidity and alkalinity of foods for proper flavor, taste and color. Examples of substances used to control acidity/alkalinity: - Yeast, Sodium Bicarbonate, Citric Acid, Fumaric Acid, Phosphoric Acid, Lactic Acid, Tartrates. Examples of food: - Cakes, Cookies, Quick Breads, Crackers, Butter, Chocolates, Soft Drinks Food Additives v. To enhance flavor or impart desired color. Many spices and natural and synthetic flavors enhance the taste of foods. Colors, likewise, enhance the appearance of certain foods to meet consumer expectations. Examples of substances used to enhance flavour/desired color: - Cloves, Ginger, Fructose, Aspartame, Saccharin, FD&C Red No.40, Monosodium Glutamate, Caramel, Chlorophyll, Annatto, Limonene, Turmeric, Riboflavin. Examples of food: - Spice Cake, Gingerbread, Soft Drinks, Yogurt, Soup, Confections, Baked Goods, Cheeses, Jams, Gum Colour Additives A color additive is any dye, pigment or substance that can impart color when added or applied to a food. Colour additives are used to: 1. Restore colour lost during processing or storage (e.g. marrowfat peas). 2. Ensure that each batch produced is identical in appearance or does not appear ‘off’. 3. Reinforces colour already in foods (e.g. enhance the yellowness of a custard). 4. Give colour to foods which otherwise would be colourless (e.g. soft drinks) and so make them more attractive. Colour Additives - Classification of Use of Colours Colors permitted for use in foods are classified as certified or exempt from certification. Certified colors are man-made, with each batch being tested by the manufacturer and FDA to ensure that they meet strict specifications for purity. - There are NINE certified colors approved for use in the United States. - One example is FD&C Yellow No.6, which is used in cereals, bakery goods, snack foods and other foods. Color additives that are exempt from certification include pigments derived from natural sources such as vegetables, minerals or animals. - For example, caramel color is produced commercially by heating sugar and other carbohydrates under strictly controlled conditions for use in sauces, gravies, soft drinks, baked goods and other foods. - Most colors exempt from certification also must meet certain legal criteria for specifications and purity. Colour Additives – Negative Effects Certain combinations of the following articifical food colours: sunset yellow (E110), quinoline yellow (E104), carmoisine (E122), allura red (E129), tartrazine (E102) and ponceau 4R (E124) have been linked to a negative effect on children’s behaviour. - These colours are used in soft drinks, sweets and ice cream. - The Food Standards Agency suggest if signs of hyperactivity or Attention Deficit Hyperactivity Disorder are seen in a child, these additives should be avoided. Colour Additives – Negative Effects i. Blue #1 (the Brilliant Blue). Brilliant Blue may cause kidney tumors in mice. Used in baked goods, beverages, desert powders, candies, cereal, drugs. ii. Blue #2 (Indigo Carmine). Causes a statistically significant incidence of tumors, particularly brain gliomas, in male rats. Used in colored beverages, candies, pet food, & other food and drugs. iii. Citrus Red #2. It's toxic to rodents at modest levels and caused tumors to the urinary bladder and possibly to other organs. Used on skins of Florida oranges. Food Additives – Flavourings and Flavour enhancers Flavourings, on the other hand, are added to a wide range of foods, usually in small amounts to give a particular taste. Flavour enhancers bring out the flavour in foods without imparting a flavour of their own. - e.g. monosodium glutamate (E612) is added to processed foods. - Some of the names MSG goes under - Monopotassium glutamate - Glutavene - Glutacyl - Glutamic acid - Autolyzed yeast extract - Calcium caseinate/Sodium caseinate - E621 (E620-625 are all glutamates) - Ajinomoto, Ac'cent - Gourmet Powder Food Additives – Flavourings and Flavour enhancers The following may also contain MSG Free glutamate content of foods natural flavours or seasonings (mg per 100g) natural beef or chicken flavouring roquefort cheese (1280) hydrolyzed milk or plant protein soy sauce (1090) textured protein fresh tomato juice (260) seasonings grape juice (258) soy sauce peas (200) bouillon mushrooms (180) broth broccoli (176) spices tomatoes (140) oysters (137) corn (130) chicken (44) mackerel (36) beef (33) eggs (23) human milk (22) Food Additives - Flavourings and Flavour enhancers The bottom line: is MSG safe? Yes!!! It's been thoroughly studied and is approved as safe by every regulatory agency on earth. - Australia/New Zealand. - US-Food and Drug Administration (US-FDA). - Joint FAO/WHO Expert Committee. - European consensus (even at ridiculously high doses, MSG had no adverse effect). Food Additives - Preservatives Food preservatives are used to: 1. Prevent the growth of micro-organisms which could cause food spoilage and lead to food poisoning 2. Extend the shelf-life of products, so that they can be distributed and sold to the consumer with a longer shelf-life. For example, bacon, ham, corned beef and other ‘cured’ meats are often treated with nitrite and nitrate (E249 to E252) during the curing process. - Nitrates/nitrites preserve, flavor and maintain a red color in many processed meat products. - Nitrites can form potent carcinogenic nitrosamines in the body (can cause prostate, breast and stomach cancers in humans). - Nitrates are associated with miscarriages, fetal deaths and birth defects in lab animals. Food Additives - Antioxidants Antioxidants aim to: 1. Prevent food containing fat or oil from going rancid due to oxidation, i.e. developing an unpleasant odour or flavour. 2. Prevent the browning of cut fruit, vegetables and fruit juices (and so increase shelf life and appearance). For example, vitamin C, also known as ascorbic acid, or E300, is one of the most widely used antioxidants. Food Additives - Sweeteners Sweeteners include: - Intense sweeteners, e.g. saccharin, have a sweetness many times that of sugar and therefore are used in small amounts, e.g. in diet foods, soft drinks, sweetening tablets - Bulk sweeteners, e.g. sorbitol, have a similar sweetness to sugar and are used at similar levels.  Food Additives - Others i. Acids, bases and buffers. Acids, bases and buffers control the acidity or alkalinity of food, for safety and stability of flavour. ii. Anti-caking agents. Anti-caking agents ensure free movement or flow of particles (e.g. in dried milk or table salt). iii. Anti – foaming agents. Anti-foaming agents prevent or disperse frothing, e.g. in the production of fruit juices. iv. Glazing agents. Glazing agents provide a protective coating or sheen on the surface of foods, e.g. confectionary (for appearance and shelf-life). Food Additives - Others v. Emulsifiers. Emulsifiers help mix ingredients together that would normally separate, e.g. Lecithins (E322). vi. Stabilisers. Stabilisers prevent ingredients from separating again, e.g. locust bean gum (E410). Emulsifers and stabilisers give food a consistent texture (e.g. they can be found in low-fat spreads). vii. Gelling agents. Gelling agents are used to change the consistency of a food, e.g. pectin (E440), which is used to make jam. viii. Thickeners. Thickeners help give food body, e.g. can be found in most sauces.