How to count on food
This week, we look at more unusual additives and bulking ingredients, prefixed E, that you may find in your favourite foods – and then move on to enzymes that can blend different proteins together, or help to peel your fruit! Finally, a word on high fruct
SOME biochemists might joke that it is a crying shame that most people are not aware of E1105 (lysozyme) – for this enzyme additive is found in human tears and other body fluids, such as saliva, amniotic fluid, etc.
Lysozyme has an interesting history, being originally identified by Alexander Fleming in 1922 as the reason why egg whites are generally antibacterial. It is also the first enzyme to be detected which contains all 20 of the common amino acids; the study of lysozyme led to the eventual understanding of how enzymes work in the body. In food, E1105’s primary function is to act as an antimicrobial preservative, particularly against early bacterial biofilms in cheeses. If you are interested in how and why biofilms develop, refer to tinyurl.com/star2-biofilm.
If you like gooey confections, oozing with liquid caramel or syrups, then you have to thank E1103 (invertase). This is an enzyme which inverts sugar (or sucrose) into a syrupy blend of glucose and fructose, which oddly actually tastes significantly sweeter than sugar itself – and with a pleasantly dense, moist texture. The inverted sugar is then mixed with flavourings and used for your mucilaginous candy bars.
And if foods have too many calories, there are additives to moderate that too, such as E1200 (polydextrose), a synthetic low-calorie polymer of glucose used to replace sugar, starch and fats in cakes, confections, desserts, cereals, beverages, salad dressings, etc. It is classed as a soluble fibre and used mostly in diet foods or meals for diabetics. E1200 is derived from the interaction of glucose with two other natural additives, E330 (citric acid) and E420 (sorbitol) – and adding E1200 to food automatically “converts” low fibre content food into high fibre food. However, one commonly-observed and problematic side effect is excessive bowel laxation, so much so that the FDA requires a warning on the food label if any portion of food contains more than 15g of polydextrose. Possibly, actor Jack Nicholson had consumed too much E1200 when he was famously quoted as saying that one can never trust a fart.
Both E1201 (polyvinylpyrrolidone) and E1202 (polyvinylpolypyrrolidone) sound more like rocket fuels than food additives, but these synthetic compounds are used quite commonly in food processing. E1201 is used as a stabiliser and water-soluble dispersant for other additives, such as flavourings. E1202 is a cross-linked version of E1201, and is not water soluble but is capable of absorbing water and swelling very rapidly – this makes it a good disintegrant (dispersal agent) for medication pills. E1202 is also used for fining (filtering) beers and wines, as it binds well with polyphenols and tannins, precipitating these impurities and thus clarifying the alcoholic liquids.
Despite its chemical name, E1203 (polyvinyl alcohol) is more likely to be encountered in your breakfast bowl than at your local rave club. It is one of the compounds used to glaze the outside of dried fruits in muesli and other breakfast cereals to prevent dehydration. Other films and glazing agents reside in the range between E1204 (pullulan) and E1209 (polyvinyl alcohol-polyethylene glycol-graft-co-polymer).
The next range between E1404 (oxidised starch) and E1452 (starch aluminium octenyl succinate) are all wheat or corn starch-based additives – they are mainly used as bulking agents, thickeners, stabilisers and anti-caking agents. The last mentioned additive, E1452, is also subject to European Union regulations for contamination by heavy metals.
The final pair of additives to be discussed are E1520 (propan-1,2-diol or propylene glycol) and E1521 (polyethylene glycol). Although both are used in anti-freeze solutions, the similarities end there. E1520 is a major component of the liquids used in e-cigarettes, used to promote the smoothness of ice creams and various dairy foods, and is also a solvent for medications which are insoluble in water.
On the other hand, E1521 is more used as a surfactant (anti-foaming agent) in foods – it is also used as a laxative and in suppositories. Another common use of E1521 is in cosmetics, where it is a flexible thickener, humectant, solvent and moisturiser – it is often labelled as “PEG” followed by a number, which indicates the molecular weight. One cautionary note is that E1521 should not be
left to oxidise, as it can
Former journalist and Senegal-based blogger Vignon-Vullierme presents a plate of pastries home-made in her Dakar kitchen. — AFP