XXVI. Supplement to former paper, entitled—"Experimental inquiry into the composition of some of the animals fed and slaughtered as human food.”—Composition of the ash of the entire animals, and of certain separated parts
In our former paper (Phil. Trans., Part II., 1859), we considered the analytical results which had then been obtained illustrating the actual and comparative composition of certain collective portions, and of the entire bodies, of animals of the farm, of different descriptions, and in different stages of growth and fatness. The results were given relating to ten animals, namely—a fat calf, a half-fat ox, a fat ox, a fat lamb, a store sheep, a half-fat old sheep, a fat sheep, a very fat sheep, a store pig, and a fat pig. The constituents which had been determined were—the total fat (by melting, expression, and ether-extraction), the total nitrogen, and the total mineral matter (ash). These were given in detail for certain separated parts, and in summary for all those parts collectively which are usually classed by the butcher as “carcass,” for all those collectively classed as “offal,” and for the entire animal (fasted live-weight). At that time the analyses of the ashes of the different animals, and their separated parts, were not completed. It is the object of this supplementary paper to record the results of forty complete ash-analyses, and to indicate their connexion with the main inquiry, and their importance as an element of it. To do this it will be desirable in the first place briefly to summarise the results and conclusions previously given. From the data above referred to, the composition of some of the separated parts, and of the entire bodies, of the ten animals was given, so far as the total mineral matter, the total nitrogenous substance, the total fat, the total dry substance, and the water are concerned.