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Food additives course Prepared by: Samer mudalal

Food additives course Prepared by: Samer mudalal. Chapter 1: introduction. To identify the reason(s) why food additives are used. To understand the different sources of food additives. To understand the different roles and functions of food additives in food. . Learning objectives.

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Food additives course Prepared by: Samer mudalal

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  1. Food additives course Prepared by: Samermudalal

  2. Chapter 1: introduction

  3. To identify the reason(s) why food additives are used. To understand the different sources of food additives. To understand the different roles and functions of food additives in food. Learning objectives

  4. Food additives are substances added to products to perform specific technological functions. These functions include preserving, i.e. increasing shelf-life or inhibiting the growth of pathogens, or adding colouring and flavouring to food for interest and variety.

  5. each of the food additives must provide some useful and acceptable function or attribute to justify its usage. Generally: 1. To improve or maintain nutritional value • Nutritional additives, fat substitutes 2. To maintain palatability and wholesomeness • Antimicrobial agents, antioxidants, anti-browning agents 3. To enhance appeal of foods • Flavors, sweeteners, colorants, texturing agents (emulsifiers, stabilizers, water holding or binding agents, dough conditioners, bulking agents)

  6. 4. To provide leavening or control pH • Leavening agents, acidulants, pH control agents 5. To aid in the processing of foods • Enzymes, non-enzymatic catalysts, antifoaming agents, propellants and gases, lubricants, chelating agents, solvents

  7. Additives may be: • natural – found naturally, such as extracts from beetroot juice (E162), used as a colouring agent; • manmade versions – synthetic identical copies of substances found naturally, such as benzoic acid (E210), used as a preservative; • artificial – produced synthetically and not found naturally, such as niasin (E234), used as a preservative in some dairy products and in semolina and tapioca puddings. Types of additives

  8. ppm - parts per million (a weight to weight ratio) • 10 to the minus six • one ounce of salt in 31 tons of potato chips • ppb - parts per billion • 10 to the minus nine • one ounce of salt in 31000 tons of potato chips • Percentage - value divided by 100 • 0.1 % is equivalent to 1000 ppm • 200 ppm is equal to 0.02% Units of Measure

  9. EEC - European Economic Community • a system which has been successfully used in Europe to label food additive use EEC - Numbering System

  10. INS - International Numbering System for Food Additives • a Codex sponsored numbering system • set out in three columns providing XOT4-EN.pdf • Identification Number • The name of the additive • The Technological Function of the Additive • For Tartrazine: (colour 102)/colour(tartrazine) • For Sodium Carboxymethyl Cellulose • (thickener 466) / thickener (sodium carboxymethyl cellulose) INS Numbering System

  11. E numbers are codes for food additives and are usually found on food labels throughout the European Union. The numbering scheme follows that of the International Numbering System (INS) as determined by the Codex Alimentarius committee. Only a subset of the INS additives are approved for use in the European Union, giving rise to the 'E' prefix. Why are additives given E numbers?

  12. • In the European common market, E numbers are given to additives as they are approved. • E-numbers are numerical designations which have been developed within the European Community (EC) for declaration of foodstuff additives. There are a number of sources for lists of E-numbers on the Internet, including: http://www.elc-eu.org/approved.htm http://www.fst.rdg.ac.uk/foodlaw/additive.htm http://www.eurunion.org/legislat/Foodstuffs/ENumbers.htm

  13. EU legislation requires most additives used in foods to be labeled clearly in the list of ingredients, either by name or by an E number. This provides you with information about the use of additives in foods and allows you to avoid foods containing specific additives if you wish. Giving an additive an E number means that it has passed safety tests and has been approved for use in the European Union.

  14. The E numbers are categorized as follows: • E100–E199 (colours) • E200–E299 (preservatives) • E300–E399 (antioxidants, acidity regulators) • E400–E499 (thickeners, stabilizers, emulsifiers) • E500–E599 (acidity regulators, anti-caking agents) • E600–E699 (flavour enhancers) • E900–E999 (surface coating agents, gases, sweeteners ) • E1000–E1999 (additional chemicals)

  15. Preservatives aim to: • prevent the growth of micro-organisms which could cause food spoilage and lead to food poisoning; • 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. Preservatives

  16. Antioxidants aim to: • prevent food containing fat or oil from going rancid due to oxidation, i.e. developing an unpleasant odour or flavour; • 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 Antioxidant

  17. Colours aim to: • restore colour lost during processing or storage • ensure that each batch produced is identical in appearance or does not appear ‘off’; • reinforces colour already in foods, e.g. enhance the yellowness of a custard; • give colour to foods which otherwise would be colourless (e.g. soft drinks) and so make them more attractive. Colours

  18. 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.

  19. 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. For example some soups, sauces and sausages. Flavourings, on the other hand, are added to a wide range of foods, usually in small amounts to give a particular taste. These do not have E numbers because they are controlled by different food laws. Ingredients lists will say if flavourings have been used, but individual flavourings might not be named Flavour enhancers

  20. 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. If concentrated cordial drinks that contain sweeteners are given to children between the ages of 6 months to 4 years, it is important to dilute them more than for adults. Infants under 6 months should not be given cordial drinks Sweeteners

  21. Acids, bases and buffers control the acidity or alkalinity of food, for safety and stability of flavour. Acids, bases and buffers

  22. Anti-caking agents Anti-caking agents ensure free movement or flow of particles, e.g. in dried milk or table salt. Anti-foaming agents Anti-foaming agents prevent or disperse frothing, e.g. in the production of fruit juices.

  23. Glazing agents provide a protective coating or sheen on the surface of foods, e.g. confectionary (for appearance and shelf-life). Glazing agents

  24. Emulsifiers help mix ingredients together that would normally separate, e.g. Lecithins (E322). 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. Gelling agents are used to change the consistency of a food, e.g. pectin (E440), which is used to make jam. Thickeners help give food body, e.g. can be found in most sauces. Emulsifiers, stabilisers, gelling agentsand thickeners

  25. Chapter 2: Assessing Food Additive Safety

  26. • USA – Responsible agency: Food and Drug Administration (FDA) • Others: Food Safety Inspection Service (FSIS), United Stated Department of Agriculture (USDA), National Marine Fisheries Service (NMFS) • FDA approves use of food additives in USA and sets limits on appropriate usage applications and levels Regulatory Status of Food Ingredients

  27. Other countries – FAO/WHO Joint Expert Committee on Food Additives (JECFA) • Judges safety of food ingredients on a worldwide basis • Establishes acceptable daily intakes for specific food additives • Many countries contribute to JECFA activities – Each country has its own regulations

  28. Food/Ingredient Analysis • Association of Official Analytical Chemists – AOAC Official Methods of Analysis – www.aoac.org

  29. No Observed Effect Level (NOEL) Estimated to be the no observed effect level in animals, divided by a 100 (sometimes a 1000) safety factor Terms

  30. Estimated to be the no observed effect level in animals, divided by a 100 Sometimes a 1000 safety factor depending on the nature of toxic effects noted and quality of available toxicity data The dietary intake of an additive which can be safely ingested over a lifetime without appreciable risk from the known information Acceptable Daily Intake (ADI)

  31. It is determined that a 1 kg rat could consume without effect 300,000 mg daily, the no effect level expressed per unit of body weight would be 3000 mg/kg/day • the ADI (using a 100 safety factor) would be 30 mg/kg/day For Example:

  32. Classification of Toxicological Tests Sensitization Studies Pharmacokinetic Studies Acute Oral Toxicity Studies 28- day Oral Toxicity Study Reproduction Studies (Oral) One - year Oral Toxicity Study Teratogenicity Studies (Oral) 90- day Oral Toxicity Study Genotoxicity Tests Classification of Toxicological Testing

  33. LD 50 test • this is a test for the dose of the additive which is level (deadly) to 50% of the animals when given only once • several animal species are tested • the lower the LD 50, the higher the toxicity Another Term for Evaluating Chemical Toxicity (eg. pesticides)

  34. Taking the Barometer Reading for Food Additive Control Do additives meet Food Chemical Codex Specifications Are certificates of analysis obtained from suppliers for each additive lot Does the firm have additive training and use trained staff Potential For Food Additive Problems Are verification checks of additive quality conducted Does the firm keep additives which are not permitted in their products Are written recipes used for addition of food additives Does firm have additive measuring equipment Are food additives correctly labelled and stored properly Does plant management routinely verify and update the procedures for adding food additives

  35. Chapter 3: acids , bases, and Chemical Leavening Systems

  36. Acids are added for numerous purposes in foods and food processing, where they provide the benefits of many of their natural actions. One of the most important functions of acids in Foods: • is participation in buffering systems. • The use of acids and acid salts in chemical leavening systems, • the role of specific acidic microbial inhibitors (e.g., sorbic acid, benzoic acid) in food preservation • the function of acids as chelating agents. • Acids are important in the setting of pectin gels • they serve as defoaming agents and emulsifiers, and they induce coagulation of milk proteins in the production of cheese and cultured dairy products such as sour cream 1. Acids1.1 General Attributes

  37. In natural culturing processes, lactic acid (CH3-CHOH-COOH) produced by streptococci and lactobacilli causes coagulation by lowering the pH to near the isoelectric point of casein. Cheeses can be produced by adding rennet and acidulants such as citric acid and hydrochloric acids to cold milk (4–8°C). Subsequent warming of the milk (to 35°C) produces a uniform gel structure. Addition of acid to warm milk results in a protein precipitate rather than a gel.

  38. d-Gluconolactone also can be used for slow acid production in cultured dairy products and chemical leavening systems because it slowly hydrolyzes in aqueous systems to form gluconic acid (Fig. 1). Dehydration of lactic acid yields lactide, a cylicdilactone (Fig. 2), which also can be used as a slow-release acid in aqueous systems.

  39. Acids such as citric are added to some moderately acid fruits and vegetables to lower the pH to a value below 4.5. In canned foods this permits sterilization to be achieved under less severe thermal conditions than is necessary for less acid products and has the added advantage of precluding the growth of hazardous microorganisms (i.e., Clostridium botulinum).

  40. One of the most important contributions of acids to foods is their ability to produce a sour or tart taste. Acids also have the ability to modify and intensify the taste perception of other flavoring agents. The hydrogen ion or hydronium ion (H3O+) is involved in the generation of the sour taste response. Furthermore, short-chain free fatty acids (C2-C12) contribute significantly to the aroma of foods. For example, buytric acid at relatively high concentrations contributes strongly to the characteristic flavor of hydrolytic rancidity, but at lower concentrations contributes to the typical flavor of products such as cheese and butter.

  41. Numerous organic acids are available for food applications . Some of the more commonly used acids are acetic (CH3COOH), lactic (CH3-CHOH-COOH), citric [HOOC-CH2-COH(COOH)-CH2-COOH], malic (HOOC-CHOH-CH2-COOH), fumaric (HOOC-CH=CH-COOH), succinic (HOOC-CH2-CH2-COOH), and tartaric (HOOC-CHOH-CHOHCOOH). Phosphoric acid (H3PO4) is the only inorganic acid extensively employed as a food acidulant. Phosphoric acid is an important acidulant in flavored carbonated beverages, particularly in colas and root beer. The other mineral acids (e.g., HCl, H2SO4) are usually too highly dissociated for food applications, and their use may lead to problems with quality attributes of foods.

  42. Chemical leavening systems are composed of compounds that react to release gas in a dough or batter under appropriate conditions of moisture and temperature. During baking, this gas release, along with expansion of entrapped air and moisture vapor, imparts a characteristic porous, cellular structure to finished goods. Chemical leavening systems are found in self-rising flours, prepared baking mixes, household and commercial baking powders, and refrigerated dough products Chemical Leavening Systems

  43. Carbon dioxide is the only gas generated from currently used chemical leavening systems, and it is derived from a carbonate or bicarbonate salt. The most common leavening salt is sodium bicarbonate (NaHCO3), although ammonium carbonate [(NH4)2CO3] and bicarbonate (NH4HCO3) are sometimes used in cookies. Both of the ammonium salts decompose at baking temperatures and thus do not require, as does sodium bicarbonate, an added leavening acid for functionality. Potassium bicarbonate (KHCO3) has been employed as a component of leavening systems in reduced-sodium diets, but its application is somewhat limited because of its hygroscopic nature and slightly bitter flavor.

  44. The proper balance of acid and sodium bicarbonate is essential because excess sodium bicarbonate imparts a soapy taste to bakery products; an excess of acid leads to tartness and sometim bitterness. However, in the presence of natural flour ingredients, the amount of leavening acid required to give neutrality or any other desired pH in a baked product may be quite different from the theoretical amount determined for a simple system. Still, neutralizing values are useful in determining initial formulations for leavening systems. Residual salts from a properly balanced leavening process help stabilize the pH of finished products.

  45. Baking powders account for a large part of the chemical leaveners used both in the home and in bakeries. These preparations include sodium bicarbonate, suitable leavening acids, and starch and other extenders. Federal standards for baking powder require that the formula must yield at least 12% by weight of available carbon dioxide, and most contain 26–30% by weight of sodium bicarbonate. In addition to NaHCO3 and starch, these baking powders usually contain monocalcium phosphate monohydrate [Ca(HPO4)2 · H2O], which provides rapid action during the mixing stage, and sodium aluminum sulfate [Na2SO4 · Al2(SO4)3],which does not react appreciably until the temperature increases during baking

  46. The increase in convenience foods has stimulated sales of prepared baking mixes and refrigerated dough products. In white and yellow cake mixes, the most widely used blend of leavening acids contains anhydrous monocalcium phosphate [Ca(HPO4)2] and sodium aluminum phosphate [NaH14Al3(PO4)8 · 4H2O]; chocolate cake mixes usually contain anhydrous monocalcium phosphate and sodium acid pyrophosphate (Na2H2P2O7) . Typical blends of acids contain 10–20% fast-acting anhydrous monophosphate compounds and 80–90% of the slower acting sodium aluminum phosphate or sodium acid pyrophosphate

  47. The leavening acids in prepared biscuit mixes usually consist of 30–50% anhydrous monocalcium phosphate and 50–70% sodium aluminum phosphate or sodium acid pyrophosphate. The earliest self-rising flours and cornmeal mixes contained monocalcium phosphate monohydrate [Ca(HPO4)2 · H2O], but coated anhydrous monocalcium phosphate and sodium aluminum phosphate are in common use

  48. Basic or alkaline substances are used in a variety of applications in foods and food processing. Although the majority of applications involve buffering and pH adjustments, other functions include carbon dioxide evolution, enhancement of color and flavor, solubilization of proteins, and chemical peeling. The role of carbonate and bicarbonate salts in carbon dioxide production during baking has been discussed previously. 2. Bases

  49. Alkali treatments are imposed on several food products for the purpose of color and flavor improvement. Ripe olives are treated with solutions of sodium hydroxide (0.25–2.0%) to aid in the removal of the bitter principal and to develop a darker color. Pretzels are dipped in a solution of 1.25% sodium hydroxide at 87–88°C (186–190°F) prior to baking to alter proteins and starch so that the surface becomes smooth and develops a deep-brown color during baking.

  50. Soy proteins are solubilized through alkali processing, and concern has been expressed about alkaline-induced racemization of amino acids and losses of other nutrients. Small amounts of sodium bicarbonate are used in the manufacture of peanut brittle candy to enhance caramelization and browning, and to provide, through release of carbon dioxide, a somewhat porous structure. Bases, usually potassium carbonate, are also used in cocoa processing for the production of dark chocolate. The elevated pH enhances sugar-amino browning reactions and polymerization of flavonoids , resulting in a smoother, less acid and less bitter chocolate flavor, a darker color, and a slightly improved solubility.

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