388 AGRICULTURAL CHEMISTRY 



contain some refuse material which cannot be consumed 

 as food. In average meat, as purchased in the market, 

 from 7 to 56 per cent, is bone and trimmings. Round 

 steak has least waste while shank has most. Tables 

 showing the average amounts of refuse in meats are given 

 at the close of the chapter. The amount of refuse and 

 waste which a food contains is frequently large enough 

 to make the nutrients of the edible portion quite expen- 

 sive even in apparently cheap foods. In vegetables, the 

 refuse ranges from 15 to 50 per cent. About 15 per 

 cent, of the weight of potatoes is lost as parings ; of fresh 

 peas, one- half of the weight is pods, and of squash, one- 

 half the weight is rind and seeds. In calculating the 

 nutrients of foods, the refuse and waste parts are to be 

 considered, as there is nearly always a smaller percentage 

 amount of nutrients in the food as purchased than in the 

 edible portion. 



510. Loss of Nutrients in the Preparation of Foods. 

 In the cooking of vegetables, as potatoes, carrots and 

 cabbage, some of the soluble nutrients, as albumin, sugar 

 and mineral matter are extracted and lost in the water. 

 In the case of potatoes, experiments have shown that 

 over 57 per cent, of the total nitrogenous matter is ex- 

 tracted and lost when the potatoes are cut in small pieces 

 and soaked in cold water. When the cleaned, unpeeled 

 potatoes were placed directly into hot water, the losses 

 amounted to only i per cent. In the case of carrots and 

 cabbage, the losses are large if the pieces are small and 

 much water is used. The losses from meats incident to 

 cooking need not necessarily be large provided mechani- 



