UNIT 6 - FOOD ADDITIVES

INTRODUCTION

• Food additives are substances added to food to preserve flavour or enhance its taste, appearance, or other qualities. 
• Some additives have been used for centuries; for example, preserving food by pickling (with vinegar), salting, as with bacon, preserving sweets or using sulfur dioxide as with wines. 
• With the advent of processed foods in the second half of the twentieth century, many more additives have been introduced, of both natural and artificial origin.

What Is a Food Additive?

• In its broadest sense, a food additive is any substance added to food. Legally, the term refers to “any substance the intended use of which affects the characteristics of any food.” 
• This definition includes any substance used in the production, processing, treatment, packaging, transportation or storage of food.
• Direct food additives are those that are added to a food for a specific purpose in that food. For example, xanthan gum — used in salad dressings, chocolate milk, bakery fillings, puddings and other foods to add texture — is a direct additive. Most direct additives are identified on the ingredient label of foods.
• 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.

Examples of Food Additives

• There are many food additives that are used as a preservative, such as ascorbic acid, potassium sorbate, sodium nitrite, and calcium sorbate. 
• These food additives can prevent oxidation of fats, which cause an off-flavour to develop; prevent the growth of microbes by changing the acidity, and prevent other changes in flavour. 
• Preservative-type food additives can be found in anything from canned fruits and vegetables to bread and meats.
• Nutrients are frequently added to food, such as adding iron and thiamine into flour. Sometimes these nutrients are even mandated by law to be added. 
• Since most nutrients are removed from flour in the processing, the government requires producers to add many of the nutrients back into the flour. 
• Other times nutrients are added simply to increase the nutritional value of the product.

Types of Food Additives

• Preservatives
• Anti-Oxidants
• Sweeteners
• Food Colourings
• Flavourings
• Stabilisers & Emulsifiers

DIFFERENT TYPES OF FOOD ADDITIVES

• Preservatives: ascorbic acid, calcium sorbate, and sodium nitrite
• Color additives: fruit and vegetable juices, yellow 5, and beta-carotene
• Flavors and spices: ‘real’ vanilla or ‘artificial’ vanilla
• Flavor enhancers: MSG and yeast
• Emulsifiers: soy lecithin, mono and diglycerides
• Stabilizers and thickening agents: whey, guar gum, and gelatin

Preservatives

Preservative, in foods, any of numerous chemical additives used to prevent or retard spoilage caused by chemical changes, e.g., oxidation or the growth of mould. Along with emulsifying and stabilizing agents, preservatives also help to maintain freshness of appearance and consistency.

Natural Food Preservatives:
Sugar and salt are the earliest natural food preservatives that very efficiently drop the growth of bacteria in food. To preserve meat and fish, salt is still used as a natural food preservative. Alcohol and Vinegar are also common food preservatives.

Examples of chemical food preservatives are:
Benzoates (such as sodium benzoate, benzoic acid)
Nitrites (such as sodium nitrite)
Sulphites (such as sulphur dioxide)
Sorbates (such as sodium sorbate, potassium sorbate.

Anti-oxidants

Oxidation is a real problem for food products. Oxidation, for example, causes raw apples and potatoes go brown, but this can be prevented in the kitchen by adding lemon juice.
It’s very effective because lemon juice contains a very strong antioxidant – ascorbic acid or vitamin C (E300). By preventing or slowing down the oxidation process in foods, waste through spoilage is reduced.
Antioxidants are used as food additives to preserve food for a longer period of time. Antioxidants act as oxygen scavengers as the presence of oxygen in the food helps the bacteria to grow that ultimately harm the food.
Antioxidants Food Additives List

• E300 – Ascorbic acid
• E301 – Sodium ascorbate 
• E302 – Calcium ascorbate 
• E304 – Fatty acid esters of ascorbic acid 
• E306 – Tocopherols 
• E307 – Alpha-tocopherol 
• E308 – Gamma-tocopherol 
• E309 – Delta-tocopherol 
• E310 – Propyl gallate 
• E311 – Octyl gallate 
• E312 – Dodecyl gallate 
• E315 – Erythorbic acid 
• E316 – Sodium erythorbate 
• E312 – Dodecyl gallate 
• E319 – Tertiary-butyl hydroquinone (TBHQ)
• E320 – Butylated hydroxyanisole (BHA) 
• E321 – Butylated hydroxytoluene (BHT) 
• E330 – Citric Acid 
• E586 – Hexylresorcinol

Sweeteners

A sugar substitute is a food additive that provides a sweet taste like that of sugar while containing significantly less food energy. Some sugar substitutes are produced by nature, and others produced synthetically. Those that are not produced by nature are, in general, called artificial sweeteners.
Uses for artificial sweeteners
Artificial sweeteners are widely used for special situations like
Diabetes management: Unlike sugar, artificial sweeteners generally don’t raise blood sugar levels because they are not carbohydrates. But it’s important to always check with your doctor or dietitian about using any sugar substitutes if you have diabetes.

Uses for artificial sweeteners
Artificial sweeteners are widely used for special situations like
Weight control: Artificial sweeteners have virtually no calories which make them appealing to include in weight loss diets. Also, you need only a fraction as compared to the regular sugar. However, the type and amount of sweetener to be used needs to be checked with a doctor or a dietitian
Avoiding tooth decay: Sweeteners also do not contribute to tooth decay, as they are not broken down to acid by bacteria in the mouth

Common Sweeteners Approved for Use in India by FSSAI
The 4 most common artificial sweeteners used in the food industry are Aspartame, Acesulphame K2, Saccharin and Sucralose.
Aspartame is a high-intensity, artificial, non-nutritive sweetener . Aspartame can be found in a variety of products like instant breakfasts, gelatin desserts, soft drinks, beverages, tabletop sweeteners, cereals, laxatives, tea beverages, sugar-free chewing gums etc.
Acesulfame potassium is a calorie-free sugar substitute (artificial sweetener), also known as Acesulfame K. Acesulfame K is 200 times sweeter than sucrose (table sugar). In carbonated drinks, it is almost always used in conjunction with another sweetener, such as aspartame or sucralose.

Saccharin and its salts have been used in a variety of beverages, foods and pharmaceuticals. Its primary function is to provide sweetness without adding calories.
Sucralose is an artificial sweetener which can be used in baking or in products that require a longer shelf life. Sucralose is used as a replacement for, or in combination with, other artificial or natural sweeteners.
There are different sets of regulations for use of artificial sweeteners in different foods as per FSSAI (Indian regulatory body).

Food Colours

Food colouring, or colour additive, is any dye, pigment or substance that imparts colour when it is added to food or drink. They come in many forms consisting of liquids, powders, gels, and pastes. Food colouring is used both in commercial food production and in domestic cooking.
FDA is responsible for regulating all colour additives to ensure that foods containing colour additives are safe to eat, contain only approved ingredients and are accurately labelled. Certified colours are synthetically produced (or human-made) and used widely because they impart an intense, uniform colour, are less expensive and blend more easily to create a variety of hues.


Color is added to food for one or more of the following reasons: (1) to replace colour lost during processing, (2) to enhance colour already present, (3) to minimize batch-to-batch variations, and (4) to colour otherwise uncoloured food.
Food Colours
Color additives are categorized as either dyes or lakes.
Dyes dissolve in water and are manufactured as powders, granules, liquids or other special-purpose forms. They can be used in beverages, dry mixes, baked goods, dairy products, jams, pudding, pie filling, yoghurt, popsicles, pet foods and a variety of other products.
Lakes are the water-insoluble form of the dye. Lakes are more stable than dyes and are ideal for colouring products containing fats and oils, or items without enough moisture to dissolve dyes. Typical uses include coated tablets, cake and doughnut mixes, cheese, margarine, candy and chewing gums.

Flavouring Agents

Flavouring agents are key food additives with hundreds of varieties of fruit, nut, seafood, spice blends, vegetables and wine which are natural flavouring agents.
Besides natural flavours, there are chemical flavours that imitate natural flavours.
Flavouring agents include flavour substances, flavour extracts or flavour preparations, which are capable of imparting flavouring properties, namely taste or odour or both to food. Flavouring agents may be of following three types:

Natural Flavours and Natural Flavouring substances means flavour preparations and single substance respectively, acceptable for human consumption, obtained exclusively by physical processes from vegetables, for human consumption. Examples: spices, fruit juices, eggs, herbs, edible yeast, vegetable juice.

Nature-Identical Flavouring Substances means substances chemically isolated from aromatic raw materials or obtained synthetically; they are chemically identical to substances present in natural products intended for human consumption, either processed or not. Example: Vanillin, the main component of vanilla beans which can be produced as a natural or a nature-identical flavouring substance.
Artificial Flavouring Substances means those substances which have not been identified in natural products intended for human consumption either processed or not. Example: Ethyl vanillin, which is artificial and smells and tastes like vanillin yet is roughly three times more taste-intensive when added to ice cream, confectionery and baked goods.

Stabilizers

A stabiliser is an additive to food which helps to preserve its structure. Typical uses include preventing oil, water emulsions from separating in products such as salad dressing; preventing ice crystals from forming in frozen food such as ice cream; and preventing fruit from settling in products such as jam, yoghurt and jellies.
Definition of Stabilisers according to Food Processing Technology
“Stabilisers are substances or chemicals that allow food ingredients, which do not mix well, to remain in a homogenous state after blending.”

The following are the most common ones used as stabilisers:

• Agar
• cellulose and cellulose derivatives
• gelatin
• guar gum
• pectin
• starch
• xanthan gum

Food stabilisers are confused with preservatives. But there is a difference between the two. Stabilisers is used to retain the physical characteristics of the food whereas as preservatives prevent the spoilage of the food. Food stabilisers increase the stability and thickness of the food by binding its large molecules.

Applications of Stabilisers for Food
Stabilisers for food are used in many kinds of products. The most common ones that use the food stabilisers are
Ice Cream
Margarine
Low-fat spreads
Dairy products
Salad dressings
Mayonnaise

Emulsifiers

An emulsion is a system containing two liquid phases, one of which is dispersed as globules in the other.
There are two basic types of emulsions: oil-in-water (O/W) and water-in-oil (W/O). These emulsions are exactly what they sound like, as pictured below.

Foods that consist of such emulsions include butter, margarine, salad dressings, mayonnaise, and ice cream. Stabilizers maintain emulsions in a stable form.