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Unit 2 Lesson 14 - Additives

= TASK 1 = Download and complete the additives worksheet below while watching the "Food Additives" DVD. Identify the function of each additive and examples of other food products that the additive are used in. Use the websites below and the information on this page to help you. [] []

**Currently you cannot download this sheet using Firefox, so please use: Chrome, Safari, or IE**


 * What are food additives?**

media type="custom" key="4996463" Food additives are substances added to foods to perform a specific function. These functions include preserving the food (increasing the shelf life or slowing the growth of micro organisms), changing the appearance or taste of the food by adding colour or flavour and processing the food by adding special agents that help the ingredients bind together. Additives may be natural, nature identical or artificial.
 * Natural additives are substances found naturally in a foodstuff and are extracted from this food to be used in another, for example beetroot juice with its bright purple colour can be used to colour other foods such as sweets.
 * Nature identical additives are manmade copies of substances that occur naturally. For example, benzoic acid is a substance that is found in nature and is made synthetically and used as a preservative.
 * Artificial additives are substances made synthetically and are not found naturally. An example is azodicarbonamide, a flour improver that is used to help bread dough hold together


 * Why do we use them? **

Additives are used to:
 * keep food wholesome until it is eaten;
 * make the food look or taste better;
 * ensure that the food is convenient to store or use;
 * keep the price of the food competitive;
 * make the food healthier (higher in vitamins or lower in fat);
 * aid processing and manufacture.

= **E Numbers**... =
 * How are they controlled? **

All approved additives are given a number and some are also awarded an ‘E’. An E shows the additive has been accepted as safe all over the European Community. Any number with no E means the additive has been approved by the UK, but not yet by the European Union. Once the additive has been approved it must remain approved by regular repeat testing. Food labels give information about most additives present so that consumers can make informed choices.


 * THE ROLE OF SUGAR & ARTIFICAL SWEETENERS IN THE DESIGN OF FOOD PRODUCTS **

Sweetness is an important characteristic of many food products. Sweetness can be imparted by sugar or artificial sweeteners. However, sugar provides other benefits to food products. It contributes to the mouth feel of products and to their storage properties.

All sugars are sweet but they do not all have the same degree of sweetness. The sweetness of different sugars may be compared, using a point scale in which the sweetness of sucrose is taken as 100.
 * SWEETNESS**


 * THE ROLE OF THICKENERS IN THE DESIGN OF FOOD PRODUCTS**


 * THICKENING AND GELLING AGENTS**


 * Thickners** are food additives used to thicken foods. These substances can be referred to as hydrocolloids and they are capable of holding large quantities of water within their structures, or joined to their large molecules. There are many substances which have this property, including carbohydrates such as pectin, many gums and a few animal products particularly gelatine and they can be used to modify the texture and consistency of foods. Natural starches are often unsuitable due to the effects of processing, such as high temperature and freezing. Thickeners are frequently used in ice cream and instant dessert.

A very thick/**VISCOUS** product is known as a **GEL** and an ingredient producing this is called a **__GELLING AGENT__** e.g. pectin, starch, carrageenans and gelatine.

Starches thicken mixtures by a process called **GELATINISATION.**
 * STARCH**

(a) From pork skin treated with acid. (b) From beef bones and calfskin treated with alkali. It is used to set cheesecakes and table jellies etc.
 * GELATINE:** is extracted from an animal source and is a protein. Gelatine swells in cold water, is soluble in hot water and forms a GEL that sets at 20°C and melts at 30°C. Gelatine is available in 2 types:

Vegetarian forms of gelatine are also available and known as: 
 * Agar Agar (E406) - derived from red sea vegetables
 * Carageenan (E407) - derived from seaweed

Preservatives – help keep food safe for longer. Consumers can buy foods in advance of using them and so do not need to shop so often, or use up food quickly and food companies can supply food in bulk, which saves transport costs. Preservatives can also help shops offer a wider variety of choice as foods can be safely imported or can be available out of season. Eating a variety of foods is important for good health.
 * THE FUNCTION OF PRESERVATIVES IN FOOD **

Antioxidants – stop oils and fats in foods from combining with oxygen and turning rancid. Rancid fats smell and taste unpleasant and are a health risk. Antioxidants are also used in fruits, vegetables and juice to extend the shelf life.
 * THE ROLE OF ANTIOXIDANTS IN FOOD **

Emulsifiers and stabilisers – emulsifiers help mix together ingredients like oil and water that would normally separate; stabilisers prevent them from separating again. They are used in foods such as ice cream.
 * EMULSIONS**


 * EMULSIFICATION OF OIL AND WATER**

Oil and water do not mix naturally but if they are ‘forced’ together by thorough mixing, they stay in an **emulsion** (in suspension) for a very short time. If left, they will separate out, with oil floating on top of the water. To keep the mixture in **suspension**, an **emulsifier** must be introduced. One example of a natural emulsifying agent is egg yolk, which contains **lecithin**. This acts as an emulsifier when added to mixtures such as **mayonnaise**. Another example of a food emulsion is **__milk__**; the fat globules in milk are reduced in size to a small uniform diameter and are evenly distributed throughout the water. This process is known as homogenisation and is used in the production of regular low fat milks. Blends of emulsifiers are used in the food industry in a large range of products where it is necessary to prevent fat separation, for example in margarine, ice cream, syrups, salad dressing and desserts. Emulsifiers are commonly used in doughs and batters, salad dressings and ice cream.

= FOOD FORTIFICATION = Fortified foods are smart foods which means they have been modified to replace or compensate for vitamins or minerals that are lost during manufacture. Fortifying foods increases the nutritional value of a food similar to the original ingredient or to add nutritional value to a product. Fruit juices are often fortified with Vitamin C to replicate the vitamin content of fresh juice. Yoghurt is often fortified with Vitamins A and D. Breakfast cereals are often fortified with additional nutrients such as iron, calcium, and various vitamins. [|Food Fortification]