2009_Book_FoodChemistry

430 8 Food Additives
is made to legislated regulations or definitions
provided therein. A compilation of the relative
importance of various groups of additives is
presented in Table 8.1.
8.2 Vitamins
Many food products are enriched or fortified
with vitamins to adjust for processing losses or
to increase the nutritive value. Such enrichment
is important, particularly for fruit juices, canned
vegetables, flour and bread, milk, margarine and
infant food formulations. Table 8.2 provides an
overview of vitamin enrichment of food.
Several vitamins have some desirable additional
effects. Ascorbic acid is a dough improver, but
can play a role similar to tocopherol as an antioxidant.
Carotenoids and riboflavin are used as coloring
pigments, while niacin improves the color
stability of fresh and cured and pickled meat.
8.3 Amino Acids
The increase in the nutritive value of food by addition
of essential amino acids and their derivatives
is dealt with in sections 1.2.5 and 1.4.6.3.
8.4 Minerals
Food is usually an abundant source of minerals.
Fortification is considered for iron, which is often
not fully available, and for calcium, magnesium,
copper and zinc. Iodization of salt is of importance
in iodine deficient areas (cf. 22.2.4).
8.5 Aroma Substances
The use of aroma substances of natural or synthetic
origin is of great importance (cf. Table 8.1).
The aroma compounds are dealt with in detail
in Chapter 5 and in individual sections covering
some food commodities.
8.6 Flavor Enhancers
These are compounds that enhance the aroma
of a food commodity, though they themselves
have no distinct odor or taste in the concentrations
used. An enhancer’s effect is apparent to the
senses as “feeling”, “volume”, “body” or “freshness”
(particularly in thermally processed food)
of the aroma, and also by the speed of aroma perception
(“time factor potentiator”).
Table 8.2. Examples of vitamin fortification of food
Vitamin
Food product
B 1
Cocoa powder and its products,
beverages and concentrates,
confectionary and other baked
products
B 2
Baked products, beverages
B 6
Baked and pasta products
B 12
Beverages, etc.
Pantothenic acid Baked products
Folic acid Cereals (cf. 6.3.7.2)
C
Fruit drinks, desserts, dairy
products, flour
A
Skim milk powder, breakfast
cereals (flakes), beverage
concentrates, margarine, baked
products, etc.
D
Milk, milk powder, etc.
E Various food products, e. g.
margarine
8.6.1 Monosodium Glutamate (MSG)
Glutamic acid was isolated by Ritthausen
(cf. 1.2.2.2). In 1908 Ikeda found that MSG
is the beneficial active component of the algae
Laminaria japonica, used for a long time in
Japan as a flavor improver of soup and similarly
prepared food. The consumption of MSG in 1978
was 200,000 tonnes worldwide.
The taste of MSG cannot be explained by a combination
of sweet, salty, sour and bitter tastes.
It is, as the fifth quality, of an elementary nature.
This assumption, which was made as early
as 1908 by a Japanese researcher to explain the
special taste called umami, was confirmed by the
identification of a taste receptor for MSG. The
sixth quality of taste is “fatty” (cf. 3.1). Indeed,
MSG is one of the most important taste-bearing
substances in meat (cf. 12.9) and cheese ripened