The Chemistry of Food and Nutrition | Page 3

with
the German lentils, half as much more than the original weight of the
pulse; not quite as much could be poured off the others.

G. Lentils. E. Lentils. Haricots. Cooked H. Proportion of liquid 1.5
1.25 1.20 -- Soluble dry matter 0.97 3.38 1.43 7.66 per cent. Ash 0.16
0.40 0.28 1.26 " " Alkalinity as K_{2}O 0.02 0.082 0.084 0.21 " "
The loss on soaking in cold water, unless the water is preserved, is seen
to be considerable. The split lentils, having had the protecting skin
removed, lose most. In every case the ash contained a good deal of
phosphate and lime. Potatoes are rich in important potash salts; by
boiling a large quantity is lost, by steaming less and by baking in the
skins, scarcely any. The flavour is also much better after baking.
The usual addition of common salt (sodium-chloride) to boiled potatoes
is no proper substitute for the loss of their natural saline constituents.
Natural and properly cooked foods are so rich in sodium chloride and
other salts that the addition of common salt is unnecessary. An excess
of the latter excites thirst and spoils the natural flavour of the food. It is
the custom, especially in restaurants, to add a large quantity of salt to
pulse, savoury food, potatoes and soups. Bakers' brown bread is usually
very salt, and sometimes white is also. In some persons much salt
causes irritation of the skin, and the writer has knowledge of the salt
food of vegetarian restaurants causing or increasing dandruff. As a rule,
fondness for salt is an acquired taste, and after its discontinuance for a
time, food thus flavoured becomes unpalatable.
Organic Compounds are formed by living organisms (a few can also be
produced by chemical means). They are entirely decomposed by
combustion.
The Non-Nitrogenous Organic Compounds are commonly called
carbon compounds or heat-producers, but these terms are also
descriptive of the nitrogenous compounds. These contain carbon,
hydrogen and oxygen only, and furnish by their oxidation or
combustion in the body the necessary heat, muscular and nervous
energy. The final product of their combustion is water and carbon
dioxide (carbonic acid gas).
The Carbohydrates comprise starch, sugar, gum, mucilage, pectose,
glycogen, &c.; cellulose and woody fibre are carbohydrates, but are
little capable of digestion. They contain hydrogen and oxygen in the
proportion to form water, the carbon alone being available to produce
heat by combustion. Starch is the most widely distributed food. It is
insoluble in water, but when cooked is readily digested and absorbed

by the body. Starch is readily converted into sugar, whether in plants or
animals, during digestion. There are many kinds of sugar, such as grape,
cane and milk sugars.
The Oils and Fats consist of the same elements as the carbohydrates,
but the hydrogen is in larger quantity than is necessary to form water,
and this surplus is available for the production of energy. During their
combustion in the body they produce nearly two-and-a-quarter times
(4 : 8.9 = 2.225) as much heat as the carbohydrates; but if eaten in more
than small quantities, they are not easily digested, a portion passing
away by the intestines. The fat in the body is not solely dependent upon
the quantity consumed as food, as an animal may become quite fat on
food containing none. A moderate quantity favours digestion and the
bodily health. In cold weather more should be taken. In the Arctic
regions the Esquimaux consume enormous quantities. Nuts are
generally rich in oil. Oatmeal contains more than any of the other
cereals (27 analyses gave from 8 to 12.3 per cent.)
The most esteemed and dearest oil is Almond. What is called
Peach-kernel oil (Oleum Amygdalæ Persicæ), but which in commerce
includes the oil obtained from plum and apricot stones, is almost as
tasteless and useful, whilst it is considerably cheaper. It is a very
agreeable and useful food. It is often added to, as an adulterant, or
substituted for the true Almond oil. The best qualities of Olive oil are
much esteemed, though they are not as agreeable to English taste as the
oil previously mentioned. The best qualities are termed Virgin, Extra
Sublime and Sublime. Any that has been exposed for more than a short
time to the light and heat of a shop window should be rejected, as the
flavour is affected. It should be kept in a cool place. Not only does it
vary much in freedom from acid and rancidity, but is frequently
adulterated. Two other cheaper oils deserve mention. The "cold-drawn"
Arachis oil (pea-nut or earth-nut oil) has a pleasant flavour, resembling
that of kidney beans. The "cold-drawn" Sesamé oil has an agreeable
taste, and is considered equal to Olive oil for edible purposes. The best
qualities are rather difficult to obtain; those usually