This article was taken from the March 2011 issue of Wired magazine. Be the first to read Wired's articles in print before they're posted online, and get your hands on loads of additional content by subscribing online.
Each month Wired's chemist Dr John Emsley, author of nine books and 110 research papers, deconstructs an everyday product. This month: Alpen Light summer fruits bar
INGREDIENTS
>Cereals
>Oligofructose
>Apple pieces
>Apple juice
>Strawberries, raspberries and cranberries
>Sugar
>Glycerol
>Glucose syrup
>Vegetable oil
>Dextrose
>Wheat gluten
>Malted barley extract
>Milk lactose
>Milk yogurt powder
>Salt
>Maize starch
>Flavourings
>Skimmed milk powder
>Milk whey powder
>Defatted wheat germ
>Citric acid
>Lecithin
>Malic acid
>Tocopherol
>Sulphur dioxide
OLIGOFRUCTOSE
This is a carbohydrate consisting of a short chain of linked fructose units. Fructose is a simple sugar (C6H12O6) with a very sweet taste and is a major component of treacle and honey.
GLYCEROL (aka glycerine, E422 and HOCH2CH(OH)
CH2OH)
This is a humectant that keeps the bar moist as well as sweet.
There is now a world glut of glycerol because it is a by- product of biodiesel manufacture.
DEXTROSE
This is another name for D-glucose, as used in several processed foods. Its name comes from dextrorotatory glucose ("dextra" meaning "right"). It's produced by plants and can be digested easily by humans.
LECITHIN (E322)
Lecithin, an emulsifier, consists of two long-chain fatty acids bonded to phosphate. It has applications in pharmaceuticals, plastics, inks and paint - it acts as a dispersant.
MALIC ACID (E296)
This is the acid found in unripe fruit. It is also the acid tang of salt-and-vinegar crisps. And it's the acid used in many skin treatments - "chemical peels" in which the top layer of skin is scraped off.
TOCOPHEROL (E307 and C29H50O2)
A form of vitamin E and a powerful antioxidant, this is added to many cosmetics in the belief that it can neutralise the free radicals that some believe are the main cause of skin ageing.
SULPHUR DIOXIDE (SO2)
Dissolved in water, this preserves fruit. As a gas (originating from sulphur in fossil fuels) it is blamed for causing acid rain.
It is also used to make sulphuric acid, industry's most heavily used chemical.
This article was originally published by WIRED UK
