;
Testing for Coal Tar Dyes; Determining the Per Cent of
Skin in Beans; Extraction of Fat from Peanuts; Microscopic
Examination of Milk; Formaldehyde in Cream or
Milk; Gelatine in Cream or Milk; Testing for Oleomargarine;
Testing for Watering or Skimming of Milk; Boric
Acid in Meat; Microscopic Examination of Cereal Starch
Grains; Identification of Commercial Cereals; Granulation
and Color of Flour; Capacity of Flour to absorb
Water; Acidity of Flour; Moist and Dry Gluten; Gliadin
from Flour; Bread-making Test; Microscopic Examination
of Yeast; Testing Baking Powders for Alum; Testing
Baking Powders for Phosphoric Acid; Testing Baking
Powders for Ammonia; Vinegar Solids; Specific Gravity
of Vinegar; Acidity of Vinegar; Deportment of Vinegar
with Reagents; Testing Mustard for Turmeric; Examination
of Tea Leaves; Action of Iron Compounds upon
Tannic Acid; Identification of Coffee Berries; Detecting
Chicory in Coffee; Comparative Amounts of Soap Necessary
with Hard and Soft Water; Solvent Action of Water
on Lead; Suspended Matter in Water; Organic Matter
in Water; Deposition of Lime by Boiling Water; Qualitative
Tests for Minerals in Water; Testing for Nitrites
in Water.

REVIEW QUESTIONS 323

REFERENCES 350

INDEX 357

HUMAN FOODS AND THEIR NUTRITIVE VALUE

CHAPTER I

GENERAL COMPOSITION OF FOODS

1. Water.--All foods contain water. Vegetables in their natural
condition contain large amounts, often 95 per cent, while in meats there
is from 40 to 60 per cent or more. Prepared cereal products, as flour,
corn meal, and oatmeal, which are apparently dry, have from 7 to 14 per
cent. In general the amount of water in a food varies with the
mechanical structure and the conditions under which it has been
prepared, and is an important factor in estimating the value, as the
nutrients are often greatly decreased because of large amounts of water.
The water in substances as flour and meal is mechanically held in
combination with the fine particles and varies with the moisture
content, or hydroscopicity, of the air. Oftentimes foods gain or lose
water to such an extent as to affect their weight; for example, one
hundred pounds of flour containing 12 per cent of water may be reduced
in weight three pounds or more when stored in a dry place, or