E542
Bone phosphate
An anti-caking agent and mineral supplement supplying calcium and phosphorous.
Not suitable for vegetarians - made from animal bones.
E570
Stearic acid (Fatty acid)
Naturally occurring, it is one of the most common long-chain fatty acids, found in combined form with other long-chain acids, in vegetable fats and, more abundantly, animal fats, although commercial production is normally synthetic.
Named from the Greek sear, tallow, it is a colourless, waxy solid that is not readily soluble in water. Used as an anti-caking agent with no known problems.
Vegetarians beware, although unlikely, can be of animal origin.
E572
Magnesium stearate, calcium stearate
Prepared synthetically from Stearic acid (E570).
Used as an anti-caking agent and emulsifier with no known problems as a food additive.
Vegetarians beware, although unlikely, can be of animal origin.
E585
Ferrous lactate
Vegetarians beware - can be of animal origin.
E620
Glutamic acid
A non-essential amino acid, first isolated in 1865. It is the predominant amino acid in most proteins, occurring as a product of the hydrolysis of the glutamine contained in proteins, playing a vital part in brain function. The various forms of glutamic acid are known as glutamates with probably the best known being monosodium glutamate (E621).
Natural sources include meat, fish, poultry and milk, with human milk containing ten times that in cow's milk. As a food additive it is used as a flavour enhancer and salt substitute but it is reported to have the same problems as monosodium glutamate (E621). It too has been discontinued voluntarily from baby foods.
Recent research has proposed that excessive brain receptor cell activation, caused by too much glutamate, can destroy the cells. It has been further suggested that this could play a part in neurodegenerative diseases such as Alzheimer's, Parkinson's and Huntingdon's but the part that dietary glutamates contribute is still controversial.
E621
Monosodium glutamate
Often referred to as MSG, Monosodium glutamate is a white crystalline substance, the sodium salt of the amino acid glutamic acid (E620).
It was first identified as a flavour enhancer in 1908 by Professor Kikunae Ikeda of Tokyo University, Japan, who found that soup stocks made from Laminaria japonica (a seaweed which had been added to soups for centuries in Japan), contained high levels of the substance.
Ikeda decided that the unique taste, which he called umami, (delicious), was so different from the four basic tastes (bitter, salty, sour and sweet) that it was in fact a fifth taste. This view is still widely held although others say it actually only enhances the four basic tastes.
His discovery led to MSG becoming the first flavour enhancer to be used commercially. Originally production was from seaweed although it is now produced using a bacterial fermentation process with molasses (around 90% of production) or starch (10%) as carbon sources and ammonium salts as nitrogen sources.
It is found in the majority of savoury foods products, such as broths, soups, flavoured (and occasionally plain) crisps and savoury snacks, flavouring and spice blends, gravies, cooked and cured meats, pork pies, pot noodles, sausages, sauces and in other combinations.
It is also used to enhance the taste of tobacco and has been used medically to treat hepatic coma.
MSG is an important ingredient in the cuisines of China and Japan.
There have been reports that monosodium glutamate may produce in some individuals a wide range of physical reactions including, but not limited to, heart palpitations, migraine, depression, rage and mood swings, anxiety attacks, hyperactivity, burning and tingling sensations, facial tightness or pressure, thirst, cold sweats, dizziness and nausea. The amount of MSG required to cause such reactions seems to vary considerably between individuals, however, for a given individual the trigger amount will not vary significantly.
The wide range of reported reactions coupled with the varying times of reaction, which can range from almost instantly to up to 48 hours, can help to hide the fact that MSG could be the cause. However, it is reported that although different individuals will react differently, a susceptible individual will react consistently, with the same two or three reactions over the same time scale.
The substance is naturally present in its bound state, the single amino acid L-glutamic acid, in plant and animal tissues, particularly in fish, meat, milk, poultry and at high levels in tomatoes and Parmesan cheese. It is alleged that it is because, as an additive, it is in a 'free processsed' state, which comprises L-glutamic acid and D-glutamic acid together with a variety of other chemical contaminants, that it gives rise to the reported problems. The contaminants vary depending on the method of manufacture but some, such as mono and dichloro propanols and heterocyclic amines are known to be carcinogenic.
This hypersensitive reaction, Kwok's disease, first reported by Dr. Robert Ho Man Kwok in 1968, is commonly called "Chinese restaurant syndrome" because cooks in some Chinese restaurants were thought to use MSG extravagantly, (some 20% of production is used in restaurants and hotels). Some Chinese meals have been recorded as containing between 5 and 10g of MSG. It has been suggested by some research that a lack of Vitamin B6 contributes to these MSG symptoms.
However subsequent studies, including blind tests, have shown no conclusive link between the syndrome and the consumption of normal levels of MSG, around 2g daily, although tests have shown the possibility of brain cell damage in guinea pigs, hamsters, monkeys, rabbits and rats, particularly in the young. Some research appears to show that a lack of calcium appears to exacerbate the damage in adults.
Also, some research has proposed that as it is an excitotoxin, excessive brain receptor cell activation, caused by too much glutamate, can destroy the cells. It has been further suggested that this could play a part in neurodegenerative diseases such as Alzheimer's, Parkinson's and Huntingdon's but the part that dietary glutamates contribute is still controversial. (Excitotoxins are a class of chemicals that can produce brain damage by 'over exciting' neurons into firing their impulses very rapidly until they reach a state of extreme exhaustion. Several hours later these neurons can suddenly die. See alsoE951)
Recent Japanese research (October 2002) at Hirosaki University has shown that high levels fed to rats has shown vision loss and retina damage. Although these high levels would not be reached with normal additive levels, there is concern that these same effects could result from the cumulative effect of smaller amounts over a longer period of time. Lead researcher Hiroshi Ohguro says the findings might explain why, in eastern Asia, there is a high rate of normal-tension glaucoma, a form of the eye disease that leads to blindness without the usual increase in pressure inside the eyeball. The higher rate, however, could also be due to genetics.
Many food manufacturers voluntarily stopped adding MSG to baby foods.
For those trying to avoid Glutamic acid and its associated glutamates (E620 to E625) you should be aware that MSG is in most savoury products (especially convenience foods) and can also be hidden under many names. Anything with the word 'protein' or 'yeast' attached to it such as 'Hydrolysed protein' or 'Autolysed yeast' should be viewed with caution, as should the words 'seasoning' and 'natural flavour'.
Another pointer towards the possibility of MSG being present under a different name is the use of any of the additives E626 to E635 (as a quick guide look for the words guanylate or inosinate) as these can be used for their synergistic effects with MSG. For instance a 50/50 mixture of MSG and E626 (Guanylic acid) produces a flavour enhancer 100 times more potent than the same amount of MSG alone.
Just as some manufacturers have started quoting the name rather than the E number, there now seems to be a ploy amongst some manufacturers to arrange the ingredients list to ensure that 'Flavour enhancer' is split and appears on two separate lines so as to be less obvious.
E631
Disodium inosinate
Not normally suitable for vegetarians - usually made from meat or fish.
E635
Disodium 5'-ribonucleotides
Vegetarians beware - can be of animal origin.
E640
Glycine and its sodium salt
The simplest amino acid, obtainable by hydrolysis of proteins. It is the principal amino acid in sugar cane, it is colourless, sweet-tasting (Greek glykys - sweet), and in 1820 was one of the earliest of the amino acids to be isolated from gelatine (E441).
Especially rich sources include cane, gelatine and silk fibroin but it can also be prepared synthetically.
It is one of several nonessential amino acids for man as it can be synthesised from the amino acids serine (a nonessential amino acid synthesised from glucose) and threonine (an essential amino acid), as well as from other sources, and therefore does not require dietary sources.
Vegetarians beware - unlikely, but could be of animal origin.
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