[29] NUTKITIVE VALUE OF FISH AND INVERTEBRATES. 4G1 



Fulton Market, New York. A coDsiderable number of the materials in 

 Tables XI and XII were supplied by Mr. F. B. Thurber, of New York. 

 Table XII gives analyses of vegetable food materials and beverages. 

 The figures for wheat flour represent the results of forty-nine analyses 

 of American flours, of which the majority were analyzed under the di- 

 rection of Professor Brewer, aud the rest collated by him from other 

 sources for the " Eeport of the United States Census, 1880." The largest 

 iind the smallest percentages of each ingredient found in the analyses 

 are given opposite "maximum" and "minimum." The specimens of 

 bread, crackers, &c., were purchased and analyzed at Middletown, 

 Conn., and have probably about the usual composition of such materials. 

 ; With these explanations I think the tables will require no further com- 

 ment. 



COMPARATIVE COSTS OF ACTUAL NUTRIENTS IN FISH AND OTHER FOODS. 



A subject that has received but little attention in this country, though 

 it has become a vital one in Europe, and is becoming so with us, is the 

 cost of the nutritive material of our foods. The relative cheapness or 

 dearness of different foods must be judged by comparing, not the prices 

 per pound, but the costs of the actual nutrients. In making such com- 

 parisons, the cost may be as.sumed to fall, not upon the inedible portions 

 and the water, but solely lipon the three classes of nutrients: protein, 

 fats, and carbohydrates. The relative physiological value of the nutri- 

 ents in diliereut foods depends upon (J) their digestibility and (2) their 

 functions and the proj^ortions in which they can replace each other in 

 nutrition. An accurate physiological valuation is, in the present state 

 of our knowledge, at least, impracticable. The pecuniary costs of the 

 nutrients are, however, more nearly capable of approximation. 



Various methods have been proposed for computing the relative 

 pecuniary costs of the nutrients of foods, none of which, however, are 

 entirely beyond criticism. The following, based upon German* esti- 

 luates of the relative costs of protein fats and carbohydrates, is perhaps 

 as satisfactory as any. 



From extended comi)arisofts of the composition and market prices of 



the more important animal and vegetable food-materials, such as meats, 



I tish, flour, &c., those which serve for nourishment and not as luxuries, 



j nnd form the bulk of the food of the people, it has been estimated that 



a pound of protein costs, on the average, five times as much, and a 



i pound of fats three times as much, as a pound of carbohydrates ; that, 



I in other words, these three classes of nutrients stand related to each 



other, in respect to cost, in the following proportions: 



C Protein 5 



Assumed ratios of costs in staple foods : } Fats 3 



( Carbohydrates 1 



- * KiJiiig, Naliruvysmittd. I. These figures deruaud revision for our markets, but are 

 i accurate euougli for the present purpose, that of illustrating the corui)arative costli- 

 ness of the nutritive material of our foods. 



