spm chemistry chemicals for consumers

8/10/2019 SPM Chemistry Chemicals for Consumers

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Food Addictive


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Food Addictive Food Additives

Food additive = a natural / synthetic substance thatis added to food to

prevent spoilage

extend food storage life improve food appearance

improve food taste

improve food texture


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sFunction:

slow down / prevent the growth of

microorganisms / bacteria / fungi

extend food storage life.


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Example:


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Antioxidant added to food to

prevent oxidation that causes rancid fatsand brown foodsand to slow down the oxidation process.

food containing fats or oils are oxidized and becomerancid when exposed to air. This makes the foodunpalatable. The rancid products are volatile organic

compounds with 4 odours.Examples:


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Flavoring

Flavourings are the largest group of food additives.

Function : to improve the taste of food restore taste

loss due to processing.

There are 2 types of flavourings :

i)Flavour enchancers-Flavor enchancers arechemicals that are added to food to bring out the

flavours/ to enhance the tastes of food.-

Exp : monosodium glutamate (MSG) In order to

protect the public health, MSG is not allowed inbabyfoods and less used for the adults.

ii)artificial sweeteners-Exp: Aspartame

Many of compounds are used to produce artificial

flavours belong to the homologous series of esters.


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Stabilizers A substance which helps to prevent on emulsion ( oil

/water droplets suspended in water/oil droplets) from

separating out.

It is used in margarine, butter, ice cream and salad

cream.


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Thickeners

chemicals that are added to food to thicken theliquid and to prevent the food from liquefying.

They absorb water and thicken the liquid in food

to produce a jelly-like structure.

- They are natural carbohydrates


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Dyes or Colourings

chemicals that are added to food to give the colourso as to improve the appearance of food.

It is used to add or restore the colour in food in order

to

enhance its visual appeal

match consumer expectations

give colour to food that have no colour.

artificial food dyes are oftenly used as they are moreuniform, less expensive and have brighter colours

than natural food dyes.

Main trend in colour of food towards the use

of natural colours is


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Effect of Food Additives on

Health.Allergya) Food additives such as sodium sulphite (preservative),BHA

and BHT (antioxidants), MSG (flavouring) and some food colours

(e.g, Yellow No. 5) can cause allergic reactions in some people.

b) The symptoms of MSG allergy are giddiness, chest painand

difficulty in breathing. This condition is called theChinese

restaurant syndromec) The presence of sodium nitrate or sodium nitrite in foodcan

cause blue baby syndrome that is fatal for babies.This

syndrome is due to the lack of oxygen in the blood.Hence, the

use of nitrate and nitrite is allowed in babyfoods.

Cancer

a) Chemicals that cause cancer are called carcinogens.Sodium

nitrite (a preservative) is a potent carcinogen.

b) The nitrite react with the amines in food to produce

nitrosamine which can cause cancer.


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Brain damageExcessive intake of nitrites for a prolonged period of time can

cause brain damage. In this condition, the supply of oxygen to the

brain is disrupted and this cause brain damage.

Hyperact iv i tya) Food additives such as tartrazine can cause hyperactivity.

b) Children who are hyperactivity become very active, find it

difficult to relax or sleep and are very restless.


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