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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