Flavoring agents

101 Toxic Food Ingredients

101 Toxic Food Ingredients

Get Instant Access

Flavor has a profound influence on the consumption of food. It imparts that quality to products by which they distinguish themselves. Flavoring agents make up the largest number of food additives. There are three types of flavoring additives: flavorings, flavor enhancers, and (non-nutritive) sweeteners. More than 1500 substances are used as food flavorings. The majority are of natural origin or are nature-identical, and do not give rise to concern from a safety point of view. Only a few synthetic substances have been approved as food flavoring. Examples are ethylvanillin, ethylmaltol, and anisylacetone.

OC2H5 OH

Ethylvanillin

Ethylmaltol

C2H5

Ethylmaltol

CH3O

CH2COCH

CH3O

Anisylacetone

CH2COCH

Flavor enhancers intensify or modify the flavor of food. They have no taste of their own. They include substances such as monosodium glutamate (MSG) and various nucleotides. These substances are present in Japanese seaweed (traditionally used for seasoning), mushrooms, tomatoes, peas, meat, and cheese. They are often used in soups, sauces and oriental food. No known adverse effects of flavor enhancers have been reported, except for the case of MSG. Humans have been described to be sensitive to food to which MSG had been added. The symptoms include numbness, general weakness, and heart palpitations (see also Part 2, Chapter 2).

O NH2 o

Na+ O—C — CH—CH2CH2 — C — OH Monosodiumglutamate (MSG)

Sweeteners present the consumer with one of the most important taste sensations. This is reflected by the world production of sugar, which has increased from 8 million tons in 1900 to 70 million tons in 1970. For nutritional and health reasons, however, there is a growing need for sugar substitutes in food that are non-nutritive, i.e., noncaloric, and noncariogenic. Two important noncaloric synthetic sweeteners are saccharin and aspartame.

Saccharin

COOCHo

NH SO

Saccharin

NH SO

H2NCHCONHCHCH2

Aspartame

H2NCHCONHCHCH2

CH2COOH

In the US saccharin has been used commercially since 1900. It is 300 times sweeter than saccharose and very stable under almost all food processing conditions. Since World War II the consumption of saccharin has steadily increased even though its safety has been questioned repeatedly. Almost 50% of its use is in soft drinks. Individual use as table top sweetener amounts to approximately 20%. The average consumption of saccharin in the US for the whole population has been estimated at 7.1 mg/day per capita, while the intake by the subpopulation of saccharin consumers was 25 mg/day. In Europe, the average intake has been reported to be 15 mg/day.

Since the beginning of its short commercial history, saccharin has been suspected regarding its safety. In 1912 it was prohibited in the US on the basis of acute toxicity tests. However, the ban was lifted during World War I, as sugar became short in supply. After World War II, numerous studies on the toxicity of saccharin were carried out. Up to now, no mutagenicity has been found. However, long-term animal tests showed a higher incidence of bladder cancer. Although it is difficult to extrapolate from experimental animals to the human situation, it appears unlikely that the intake of saccharin at the present average level involves risks of cancer. Therefore, the use of saccharin in food is still approved in the US and in Europe.

Aspartame was discovered in the early 1960s. In the early 1980s, it was admitted in many countries as a sweetener, in addition to saccharin and cyclamate, another synthetic sweetener whose use in food has now been greatly restricted. Aspartame is a dipeptide, consisting of the amino acids phenylalanine and aspartic acid. It is 200 times sweeter than saccharose and is an excellent sweetener for dry products. At high temperature and low pH, aspartame is gradually hydrolyzed, losing its sweetness. It is suitable as table top sweetener, in chewing gum, in soft drinks, dairy products, ice cream, and dessert mixes. Since aspartame is a dipeptide, it is digested and absorbed by the body. However, the amount necessary for a sweet taste is so small that the energy produced is believed to be irrelevant.

Results from toxicity tests suggest that aspartame has no adverse effects on humans even when extreme amounts of 8 mg/kg body weight are taken in. The ADI for aspartame is 40 mg/kg body weight.

The market for sweeteners is still growing and the situation where the ADI for the known sweeteners is reached, is not inconceivable. There is, however, a need for sweeteners that are stable under specific technological conditions and are less controversial than saccharin. Although since the introduction of aspartame the use of saccharin has slowly declined, aspartame can not replace saccharin completely because of its instability when heated under acidic conditions. Therefore, the search for new sweeteners continues. At present, several non-nutritive sweeteners of natural origin are being investigated. Examples are thaumatin, a macromolecular protein sweetener from an African fruit, 2000 to 3000 times as sweet as saccharose and neohesperidin, present in orange peel, 1500 times as sweet as saccharose. Thaumatin has been admitted in the EU for use in chewing gum and sweets.

Was this article helpful?

0 0
Vegetarian Food and Cooking

Vegetarian Food and Cooking

Switch To A Vegetarian Diet And Live To Be A 100. Are You Suffering From Weak Bones And Digestive Disorders? Did You Ever Wonder About Why You Feel Restless, Listless Or Anxious Without Any Plausible Reason? The Answer Probably Lies In Your Dietary Habits.

Get My Free Ebook


Post a comment