Appendix 



COMPOSITION AND ENERGY VALUE 



OF FOODS 



The four tables making up this appendix are revisions of the tables 

 contained m the authors' previous book, Elements of Food Biochemistry . 

 The new material in these tables is taken largely from AVatt and Merrill, 

 Composition of Foods, U.S.D.A. Agricultural Handbook No. 8, 1950. A 

 small number of new entries come from Sherman, Chemistry of Food 

 and Nutrition, 7th ed., McCanse and Widdowson, The Composition of 

 Foods, and Morrison, Feeds and Feeding, 21st ed. The tables include 

 data for most of our raw food materials and for representative canned 

 foods. By comparing these data an idea can be obtained of the differ- 

 ences in composition resulting from commercial canning operations. More 

 comprehensive data on canned and cooked foods are contained in Watt 

 and Merrill and in INIcCanse and AViddowson. No data on farm rough- 

 ages have been included because of space limitations. Such data are 

 found in Morrison. 



In using these tables the student should bear in mind that the com- 

 position of any given sample that may be analyzed does not neces- 

 sarily correspond to the figures recorded here. Some variations are 

 found in the proximate composition of different samples, but greater 

 variations occur in figures for the mineral and vitamin contents. Dif- 

 ferences as great as 100 per cent may be encountered among a series 

 of plant samples. These differences are due chiefly to soil and climate 

 conditions, but they are also related to varieties and maturity of the 

 plant. From the dietary viewpoint, such variations are not serious be- 

 cause variations in different foods cancel each other. The actual intake 

 during a period of time will probably correspond closely to that cal- 

 culated from the figures of the table. 



Places marked with a question mark in Tables A-2 and A-3 indicate 

 that no quantitative data have been as yet found. A fair idea of the 

 probable amount present may be obtained by noting the figures given 

 for a similar material. For example, the magnesium and other figures 

 missing for buckwheat are probably in the same range as those given 

 for another cereal, say, barley or rye. From a nutritional viewpoint, 

 the important mineral elements are calcium, phosphorus, and iron, and 

 these elements are given for all the foods in these tables. Values for 

 sodium and chlorine are omitted as indicated by (a) , where a consider- 

 able amount of sodium chloride is added in making the product, such as 

 butter. 



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