SPM Chemistry Form 5 Notes – Chemicals for Consumers (Part 5)

by BerryBerryTeacher

in Berry Reference (Notes)

Food additives are added to food to improve its flavour, appearance and functional aspects. Most Berry Readers will imagine food additives to be of synthetic nature and involves a lot of industrial chemistry. However, this is a misconception as additives have been used since ancient times with natural food additives such as salt (salting), vinegar (pickling) and sulfur dioxide (wine preservation). The act of adding additives to food were given a large boost with the improvement in food processing technologies over the past decades.

The post, Part 5 of the series on Chemicals for Consumers by Berry Berry Easy for SPM Chemistry Form 5 chapter 5 will be on food additives. Special focus is given to food preservatives. Do read on.

[Tips: Extra knowledge. All food additives are marked by numbers as adopted by the Codex Alimentarius Commission (a collection of standards, codes of practice, guidelines related to food). The numbers, called "E Numbers" (prevalent in Europe) are preceeded by the letter E. Other countries uses the same numbers without the prefix E. The numbers given are an indication of its food additive class. For example, E100-199 are for colours, E200-299 are for preservatives, E300-399 are for antioxidants and acidity regulators, E400-499 are for stabilisers, thickeners and emulsifiers. For now, the numbers stretches to E1599. So the next time you see an E Number, try to have a look and guess its class. Although this is not an examination tips but knowing this allow you to better understand food additives.]

SPM Chemistry Form 5 Notes – Chemicals for Consumers (Part 5)

Grapeseed Oil Nutritional Information

Food Additives

Food additive = a natural / synthetic substance that is added to food to

  • prevent spoilage
  • extend food storage life
  • improve food appearance
  • improve food taste
  • improve food texture

A. Preservatives


  • slow down / prevent the growth of microorganisms / bacteria / fungi
  • extend food storage life


Preservatives Functions Example Side effect
Salt Draws the water out of the cells of microorganisms. Retards the growth of microorganisms. Salted vegetables Increase the risk of cardiovascular diseases
Sugar Draws the water out of the cells of microorganisms. Retards the growth of microorganisms. Fruit jam Tooth decay, diabetes and obesity
Vinegar Inhibits the growth of microorganisms. Pickled cucumber
Sodium nitrite / sodium nitrate Slows down the growth of microorganisms. Stabilise red colour in meats. Sausage Carcinogenic
Benzoic acid / sodium benzoate Slows down the growth of microorganisms. Tomato sauce
Sulphur dioxide Slows down the growth of microorganisms. Grape juice Asthma and allergies

Alternative ways: freezing and refrigeration

This marks the end on food preservatives. In the next part, Part 6 of notes on Chemicals for Consumers, Berry Readers will learn about antioxidants as food additives. So Form 5 Chemistry students will need to check back Berry Berry Easy for the notes. Meanwhile, study hard.

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