2.4.functional properties of additives

Question 1

what are food additives?

Answer 1

substances which are added to foods to perform specific functions. eg. flavours, colours, emulsifiers, flavour enhancers, preservatives, stabilizers, gelling agents, sweeteners, antioxidants, thickening, humectants

Question 2

What are the functions of additives?

Answer 2

-improve the colour, texture and flavour of food
-extend the shelf-life of food products
- improve the nutritional composition of a product (such as adding iron and B vitamins to breakfast cereals.)
-aid commercial production
-maintain food safety and nutritional composition.

Question 3

what are additives classed into?

Answer 3

Natural additives
Nature identical additives
Artificial additives

Question 4

what are natural additives?

Answer 4

-naturally occurring in foods.
-They are extracted from one food to be used in another. eg. beetroot juice used to colour sweets

Question 5

what are nature identical additives?

Answer 5

-are synthetic (man-made) copies of substances that occur naturally.
-For example: Benzoic acid used as a preservative; and synthetic beta-carotene is identical to the pigment found in naturally in foods.

Question 6

what are artificial additives?

Answer 6

These synthetically produced and are not naturally present in foods.
-For example: potassium sorbate is a synthetic preservative used in salad dressings and fruit squashes.

Question 7

functional properties of colours and examples

Answer 7

-used to replace colour lost during preparation, or to make food look more visually appealing.
-Synthetic colours are widely used because they can give consistent and intense colour.
-Natural colours are often more expensive than synthetic colours.
EG. Natural colours: annatto extract (yellow) caramel (yellow to tan), beta-carotene (yellow to orange).

Question 8

functional properties of sweetners and examples

Answer 8

• other than sugar, are used as to give food a sweet flavour
  -used to reduce the food energy (calories) level of foods, -make foods suitable for diabetics o
  -help avoid the effects of tooth decay caused by sugary foods.
  -Sweeteners are divided into: a) bulk sweeteners - are much sweeter than sugar and so are only used in small amounts.
  b) intense sweeteners - have a similar sweetness level to sugar so is used in similar quantities to sugar.
  -Bulk sweeteners include sorbitol and sucralose. Intense sweeteners include saccharin and aspartame.

Question 9

functional properties of flavours and examples

Answer 9

-give food a particular taste or smell
- obtained from natural ingredients or created artificially.
-Natural flavours include citrus oils, spice extracts, fruit juice concentrates
-Artificial additives include a synthetically made version of vanillin.

Question 10

functional properties of flavour enhancers and examples

Answer 10

-do not add flavour but instead enhance the existing flavour of the food.
-They may be extracted from natural sources or created artificially.
-eg.Monosodium glutamate (MSG)

Question 11

functional properties of antioxidants and examples

Answer 11

can either:
-combine with oxygen to prevent oxidation
-prevent oxygen from reacting with food which leads to spoilage.
-Without the presence of antioxidants, the oxidation of unsaturated fats would lead to rancidity which causes a bad odour and discoloration of the food.
-eg.Ascorbic acid, citric acid, sodium benzoate, calcium propionate, vitamin E, Butylated hydroxyanisole (BHA)

Question 12

functional properties of preservatives and examples

Answer 12

• prolong the shelf-life of a food by preventing or inhibiting food deterioration caused by microorganisms
  -EG. Nitrites and nitrates, Benzoic acid and benzoates,

Question 13

functional properties of emulsifiers and examples

Answer 13

• helps to maintains stable emulsion of two or more phases in a food-they enable water and oils to remain mixed together in an emulsion in foods such as: mayonnaise, ice cream, and homogenized milk.
  -EG. Mustard, soy and egg lecithin, mono- and diglycerides, polysorbates, carrageenan, guar gum and canola oil.

Question 14

functional properties of anti caking agents and examples

Answer 14

-prevent powders and granules “clumping” together.
-They function by absorbing excess moisture or by coating particles this makes the particles more water repellant, and therefore helps to prevent the clumping together of particles.
EG.Magnesium silicate and cornstarch are natural anti caking agents.
Synthetic anticaking agents include: silicon dioxide, magnesium carbonate and iron ammonium citrate.

Question 15

functional properties of humectants and examples

Answer 15

• prevent food from drying out by counteracting the effect of a dry atmosphere.(they control the moisture of foods because moisture can lead to microbial activity)
  EG.Sugar and salt have long been used at humectants. Other humectants are sugar alcohols, glucose syrup, egg yolk, egg white, molasses and lactic acid.

Question 16

functional properties of thickeners and examples

Answer 16

-increase the viscosity of foods without substantially modifying other properties.
EG. Potato starch, guar gum, xanthan gum, collagen, gelatin, agar and carrageenan.

Question 17

functional properties of stabilisers and examples

Answer 17

-help to maintain a uniform dispersion of two or more components.
- give foods a firmer texture.
-While they are not true emulsifiers, they help to stabilize emulsions.
-EG. Agar, pectin

Question 18

Who is responsible for measuring the risks associated with additives?

Answer 18

The World Health Organisation (WHO) and the Food and Agriculture Organization of the United Nations (FAO)
-An international and independent group of scientific experts called the Joint FAO/WHO Expert Committee on Food Additives (JECFA) carry out risk assessments for food additives.

Question 19

What are the risk assessments done by JECFA used for

Answer 19

-used by Codex Alimentarius Commission to establish levels for maximum use of additives in food and drinks. -The Codex Alimentarius Commission is a joint intergovernmental food standard-setting body of FAO and WHO.
-Codex standards used to set national standards to provide consumer protection, and for the international trade in food so that consumers around the world know that food they purchase meets agreed standards for safety and quality.

Question 20

advantages of additives

Answer 20

-Sensory qualities -additives can improve the colour, texture and flavour of food and therefore appeal to consumers.
- Shelf-life and food safety - can extend the shelf life of food products and help to maintain food safety.
-Nutritional value - can improve the nutritional composition of a product and also help maintain the nutritional composition of a food product that would otherwise be lost during storage of food processing. Examples of nutrients added to foods include: Vitamins A, C, D, E, and B group vitamins (thiamin, niacin, riboflavin, pyridoxine, and folic acid), These are added to foods such as wheat flour, bread, biscuits, breakfast cereals, and milk.
-aid commercial production by increasing consumer appeal through improving the sensory properties of foods

Question 21

disadvantages of additives

Answer 21

-health concerns/ have adverse health effects eg. artificial colours causing hyperactivity in children
-May also cause hives (an itchy rash)- if people are sensitive to it. headaches, respiratory problems such as asthma and digestive disorders such as diarrhoea.