October, 1912. 



KNOWLEDGE. 



mineral matters are lost. Now rice ciintains but 

 very little of these nutrients to start with, and in the 

 East the native soldiers prefer to have the liquid 

 which has been drained off, and leave the residue 

 for the English soldiers. .\11 this loss can be 

 avoided by boiling the rice (according to the 

 American receipt) in two and a half times its bulk of 

 water for twenty minutes, then placing the saucepan 

 on a tripod, covering it with a piece of cheese cloth, 

 and allowing it to remain covered for an hour ; at the 

 end the rice will be tender and sweet. As a rule all 

 vegetables, except in a very few cases, weigh more 

 after cooking ; all show a high percentage of water ; 

 so,inthecaseof lossofweight it must be due to the loss 

 of nutrients. This increase of w eight tends to make all 

 vegetable and cereal foods bulky. Onehundred ounces 

 of green artichokes after cooking weigh three hundred 

 and thirty-six ounces: one hundred ounces, brussels 

 sprouts, one hundred and twent\'-one ounces ; leeks, 

 onehundred ounces become twohundred and tiftv-two 

 ounces : one hundred ounces lentils, two hundred and 

 thirty -eight ounces ; one hundred ounces arrow root, 

 one thousand one hundred and fifteen ounces ; 

 one hundred ounces quaker oats, one thousand one 

 hundred and ten ounces ; one hundred ounces 

 mother's oats, nine hundred and twenty-five ounces ; 

 one hundred ounces rice, four hundred and eighteen 

 ounces. 



The percentage of water is one of the most impor- 

 tant points in food analysis ; we want to know how 

 much solid food we really consume. Considering 

 meat and fish there is a higher percentage of solid 

 matter, and the whole of the flesh consists of 

 nutrients, fat, protein, and mineral matter. But in 

 vegetable and cereal foods, on the other hand, besides 

 these nutrients there is a framework of cellulose or 

 woody fibre : according to some authorities this has 

 a value from the food point of view, but it is 

 doubtful. In the process of cooking the framework 

 is ruptured, and the starch inside is gelatinised; the 

 change may be observed in well-cooked potatoes. 



Table Showing Percentage of Water and Solids 



IN Various Articles of Food Before and After 



Cooking. 



The table shows the effect of cooking as 

 regards the percentage of solid matter in the cooked 

 and uncooked articles : increase in nutrients in the 

 case of fish and meat, decrease in solids w ith vege- 

 tables and cereals following the cooking |)rocess. 

 Only edible matter is considered : that is, the flesh of 

 the meat and tish, and the portion of vegetables that 

 can be eaten as food. 



At this stage it is possible to judge which foods, 

 bulk for bulk, contain most nutrients, but this does 

 not conclude the matter ; for it is further necessary 

 to know the nature and the percentage of each 

 nutrient. The human body requires certain amounts 

 of fat. carbohydrates (that is, starch and sugar), 

 mineral matter and protein daily. Protein can fulfil 

 the functions of food in all respects as a tissue 

 former, and also yields heat and energy, with the 

 help of water and mineral matters ; that is. salts such 

 as sodium chloride or table salt ; but under ordinary 

 conditions fats and carbohydrates are necessar\' as 

 energy-producers. Studies as to dietaries have been 

 made in England, America, German}-, Sweden, 

 Russia, and Japan among various classes of people, 

 those doing hard and moderate work, factory opera- 

 tives, tailors, college football teams, those emplo\'ed 

 in intellectual work, soldiers in time of peace and 

 war. Taking the average, they conform fairly well 

 to the standard draw n up by Professor Atwater : 

 four and a half ounces protein, si.xteen ounces 

 carbohydrates, and four and a-half ounces fat for a 

 man doing moderate work. To a certain e.xtent fat 

 and carbohxdrates can replace each other, and it is 

 estimated that for every part of protein four and 

 three-quarters of carbohydrates and fat are required. 

 It is understood that this standard is for the average 

 man; in the case of women, -8 of the above 

 amounts is sufficient, and children require less in 

 proportion to their age. 



At the present time there is a good deal of dis- 

 cussion on the question of proteid, and experiments 

 have been made by Professor Chittenden, of Yale, 

 and others, who state that the human body onl\- 

 needs about half of the amount mentioned above, 

 even two ounces are stated to be sulificient ; but until 

 more is known. Professor Atwater's or similar 

 standards will hold their own. 



Now the results of analysis can be stated in two 

 ways, and one of these has led to the man\- false 

 ideas which at present are in circulation among the 

 general public. The dry powdered sample must be 

 used for the estimation of fat, and so on, and in 

 many books results are stated on this basis, and the 

 important factor viz. : the percentage of water 

 present is left out of the question. The other and 

 correct method is to give tables including the water 

 and calculating the fat, and so on, in the natural 

 moist condition of the food as actualh' eaten. The 

 two following tables will illustrate the false 

 and correct method of describing the results of 

 analysis. 



