Proximate analysis of foods

The name carbohydrate dates back to a time when it was thought that all of these molecules were hydrates of carbon. For example the molecular formula for glucose is C6H1206, or six carbons plus six water molecules (H20). While these molecules make up the largest component of most foods, especially when calculated on a dry basis, their analysis was often avoided. For example, proximate analysis of food frequently involved analysis for moisture, fat, ash, and protein with the remaining portion considered carbohydrate of one form or another. 

The lipids are a group of substances found in plant and animal tissues. They are insoluble in water but soluble in common organic solvents such as benzene, ether and chloroform. They act as electron carriers, as substrate carriers in enzymic reactions, as components of biological membranes, and as sources and stores of energy. In the proximate analysis of foods they are included in the ether extract fraction.They may be classified as shown in Fig. 3.1. 

Originally the most extensive information about the composition of foods was based on a system of analysis described as the proximate analysis of foods, which was devised over 100 years ago by two German scientists, Henneberg and Stohmann. More recently, new analytical techniques have been introduced, and the information about food composition is rapidly expanding (see below). However, the system of... 

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