chapter  4
Determination of Moisture and Ash Contents of Foods
Pages 28

Water exists abundantly throughout nature, occurring

in all three physical states: gas, liquid, and solid.

Approximately 75% of the earth’s surface is covered

with water. The most significant function of liquid

water is that of supporting animal and plant life.

Because most foods originate from living matter, water

is also a primary component in many foods. The

acceptable levels of moisture vary in different food

products, and a change in this amount can have seri-

ous effects on product quality (e.g., hardening of fruit

pieces). Furthermore, the properties and qualities of

some products (e.g., powders) can be adversely influ-

enced by even minute quantities of moisture (1). The

high polarity of water results in it being unusually

reactive (1), which, along with its vast abundance and

unique properties, makes the determination of water

important not only to the food industry, but also to

the paper, plastics, and pharmaceutical industries. In the literature, the terms ‘‘water content’’ and

‘‘moisture content’’ have been used interchangeably to

indicate the quantity of water present in various food

products and ingredients. Moisture content can be exp-

ressed either as a wet basis percentage (g water/100 g

food) or a dry basis percentage (g water/100 g dry