Understanding Food Additives: Types and Functions

• Food additives are substances intentionally added to food, affecting its characteristics.
• They enhance safety, shelf life, taste, texture, or appearance.

European Legislation Definition:

• A food additive is any substance not normally consumed as a food itself or used as a characteristic ingredient, regardless of nutritive value.
• They are intentionally added for a technological purpose during manufacturing, processing, preparation, treatment, packaging, transport, or storage.
• They result or may be reasonably expected to result, directly or indirectly, as a component of such foods or their by-products.

Classes of Food Additives:

• Sensory improvers
• Preservatives
• Antioxidants
• Process aids

Sensory Improvers:

• Flavors
• Coloring substances.
• Acidulants
• Sweeteners
• Flavor enhancers

Flavors:

• Flavors, enhancers, and fragrances play a vital role in imparting taste and smell to food.
• Flavors exist in either artificial or natural forms.
• Flavourings are nature-identical compounds that are a product of synthesis or isolation using chemical procedures.
• Flavor enhancers sharpen existing flavors.
• Examples of flavor enhancers includes monosodium glutamate (MSG), monopotassium glutamate (MPG), calcium diglutamate (CDG) and monoammonium glutamate (MAG).

Colorants:

• Colorants enhance appearance, replace lost color, and retain color.
• Some colorants are natural, like carotenoids, anthocyanins, and betalains.
• Other colorants are chemically or artificially prepared, compounds like azocompounds, amaranth, brilliant blue, indigo carmine, new red, sunset yellow, tartrazine and allura.

Natural Food Colorants:

• Natural food colorants originate from plant sources,
• Anthocyanins obtained from red fruits.
• Other natural food colorants: Betanin, caramel pigment, carotenoids, lycopene, lutein, green pigments of chlorophyll, and curcumin.

Nature-Identical Food Colorants:

• Nature-identical food colourants are synthesized to chemically match natural colorants.
• Examples include carotene, canthaxanthin, and riboflavin.
• Most natural and nature-identical colors are hydrophobic.
• They are converted into sodium or potassium salt forms to become hydrophilic.
• They can be dissolved in a hydrophobic medium like oil.

Synthetic/Artificial Food Colorants:

• They are produced or synthesised using chemical processes involving molecules that impart colors to foods.
• Examples are tartrazine and carmoisine.
• Most synthetic colorants are hydrophilic.

Food Acids and Acidity Regulators:

• Used for sharpening flavors, preserving, and as antioxidants.
• Examples include acetic acid (vinegar), citric acid, tartaric acid, malic acid, fumaric acid, and lactic acid.
• Acidity regulators can organic or mineral acids, bases, neutralising agents, or buffering agents.
• They modify and control the pH of foods.

Citric Acid:

• Citric acid is prepared by fermentation of carbohydrates by fungi, specifically aspergillus niger.
• It is produced from molasses or citrus fruits.
• It provides sharp tastes, acts as an antioxidant in fatty foods, and preserves foods like meat

Lactic Acid:

• Lactic acid is produced via fermentation, with synthetic routes also being available.
• It is found in dairy products, sweets, and baked goods.

Acetic Acid:

• It is found in vinegar.
• Acetic acid is produced industrially both synthetically and by bacterial fermentation.
• Functions mainly as a flavoring and preserving agent due to antimicrobial properties.

Malic Acid:

• It is found in fruits such as bananas, apples, and tomatoes and low-energy drinks.

Fumaric Acid:

• Strong flavor
• Low solubility in aqueous media
• Produced by synthesis using malic acid as a starting material

Tartaric Acid:

• As emulsifiers, they are used in baking and confectioneries.
• Synthetically produced using maleic anhydride, extracted from wine products.

Phosphoric Acid:

• Phosphoric acid salts are used in foods to provide buffering, such as in baking powders.

Sweeteners:

• Sweeteners are added to foods for flavoring and as supplements.
• Nutritive sweeteners include sugar alcohols like glycol, glycerol, erythritol, threitol, and arabitol.
• Natural sweeteners include honey.

Synthetic Sweeteners:

• Aspartame: Methyl ester of some amino acids. 200 times sweeter than sucrose.
• Sucralose: Chlorinated sugar, 600 times sweeter than sucrose, heat stable and used in fried and baked products, beverages, chewing gums and frozen desserts.
• Acesulfame K (950): 130-200 times sweeter than sucrose.

Preservatives:

• Food preservatives prevent spoilage and extend shelf life.
• They inhibit microorganism growth, such as bacteria, yeasts, and molds.
• Food preservatives prevent food from browning, discoloring, or developing off-flavors.

Natural Preservatives:

• Lactoperoxidase in milk.
• Lysozyme in egg white.
• Saponins and flavonoids from herbs and spices.
• Bacteriocins from probiotic lactic acid bacteria.

Commercially Available Preservatives:

• Acetic acid (vinegar)
• Ascorbic acid
• Citric acid
• Potassium sorbate
• Sodium benzoate
• Sodium metabisulfite
• Sulfur dioxide
• Nitrites and Nitrates

Sodium metabisulfite:

• It is a food additive used as a preservative, bleaching agent, and relaxing agent in food processing.
• It is soluble in water and ethanol.

Antioxidants:

• Food antioxidants can neutralise free radicals in order to play an important role.
• They donate electrons to free radicals, terminating the radical chain reaction.
• Antioxidants reduce oxidative deterioration, preventing rancidity, loss of flavor, color, and nutritive value.
• Fats, oils, flavoring substances, vitamins, and colors oxidize spontaneously with oxygen when exposed to air.
• Deterioration rates vary based on natural antioxidants, oxygen availability, and sensitivity of the substance to oxidation, temperature, and light.
• Some remove oxygen via self-oxidation, as seen with ascorbic acid.
• Others interfere in the oxidation mechanism, like tocopherols, gallic acid esters, BHA, and BHT.
• Sequestering agents, like citric acid, have synergistic effects by reducing metal ions' availability.
• Powerful synthetic antioxidants BHA, BHT, and gallic acid esters are restricted.

Processing Aids:

• Flour Treatment/Improving Agents, flour needs improved properties to prepare bakery products.
• Properties, such as colour, texture, softness, and fineness must be improved.
• Includes flour maturing and bleaching agents.
• Flour maturing agents are food additives to improve baking.
• They strengthen the gluten network, allowing dough to hold gas and produce higher-rising bread.
• Examples: Ascorbic acid (vitamin C), azo-dicarbonamide (ADA), ammonium persulfate, potassium bromate.
• Flour bleaching agents are additives to flour to make it appear whiter and improve baking.
• They oxidise pigments in the flour, breaking them down and making them colourless.
• Examples include benzoyl peroxide, calcium peroxide, chlorine gas, and nitrogen dioxide.
• Anticaking Agents are processing aids that prevent the caking of granular food items, which affects food quality.

Synthetic Anticaking Agents:

• Calcium silicate (CaSiO3).
• Magnesium carbonate (MgCO3).
• Baking soda (e.G. Sodium bicarbonate or NaHCO3).
• Sodium ferrocyanide (Na4Fe (CN)6).

Natural Anticaking Agents:

• Includes kaolin, talc and bentonite.
• Talc is a powdered natural hydrated magnesium silicate containing varying proportions of materials as alpha-quartz, calcite, chlorite, dolomite, magnesite.
• Humectants keep products moist and prevent any loss of quality by attracting water molecules.
• Permitted humectants: Glycerol, Sorbitol, Mannitol.

Emulsifiers:

• Food emulsifiers create homogeneous mixtures of immiscible components like oil and water.
• Food emulsifiers are molecules with a hydrophilic and a hydrophobic part.

Oil in Water Emulsions:

• Milk
• Salad Dressings

Water in Oil Emulsions:

• Butter
• Margarine

Air in Water Emulsions:

• Whipped cream
• Ice cream
• Emulsifiers improve food palatability, maximise aeration, reduce stickiness, and enhance flavour and textural properties.
• Lecithin stabilizes mayonnaise.
• Mono- and di-glycerides keep water and oil together in margarine.
• Polysorbates create a smooth texture in ice cream.
• Xanthan gum keeps sauces and dressings smooth and creamy.

Stabilisers, Gums, Thickeners, and Gelling Agents:

• Stabilisers, thickeners or gelling agents add to food items to give them a firmer texture.
• The molecules used as stabilisers or thickeners increase viscosity or gel formation in aqueous media.
• Most widely used stabilisers in the food industry: Carrageenans, Alginates, Agar, Guar gum, Arabic gum, Xanthan gum, and Carboxymethylcellulose.

Functions of Food Additives:

• Prolong shelf life
• Improve functional properties
• Facilitate the process
• Enhance consumer acceptance
• Reduce wastage
• Make food more readily available

Identification of Food Additives:

• INS numbers stand for the International Numbering System for Food Additives.
• They are assigned by the Codex Alimentarius Commission, which is a joint committee of the Food and Agriculture Organization of the United Nations (FAO) and the World Health Organization (WHO).
• INS numbers are three or four digits, potentially followed by an alphabetical suffix for the different forms of the additive.
• E numbers are European Food Additive Numbers, which were developed to help consumers identify food additives.

Explore food additives and their role in enhancing food characteristics such as safety, taste, and appearance. Learn the definition of food additives according to European legislation and delve into classes like sensory improvers, preservatives, and process aids. Discover different types of sensory improvers, including flavors, coloring substances, sweeteners and flavor enhancers.