THE NATURE OF BUTTER FAT

New Zealand Mail, Issue 1651, 21 October 1903, Page 59

THE NATURE OF BUTTER FAT

11l an elaborate paper dealing with ihe nature of butter fat and the causes which affect its character, Dr Tharp, the chief chemist at So-m-erset House, advances some statements which must be of interest to those who._are concerned in the scientific side of the question. Though the majority of people regard fat as a practically indivisible substance, it is in reality, it apjiears, of an extremely composite character. Butter fat, which is not the same thing as butter, for butter contains water and certain impurities, ie composed of glycerine combined with various acids, the most common and important of them being oleic, palmitic, and stearic acids. _Bi' Thorp shows that there are at least twelve acids. ivith molecular weights, varying from 60 in the case of acetic acid to 316 in the cac~e of dioxystearic acid. Butter is composed, in facti of the glycerides of certain fatty acids, and lie believes it to be piractioallv certain that there art* tri-glycerides in. which one molecule of glycerine is combined with three molecules of acid, although it is not certain that the three molecules are respectively of one and the same acid in all cases It is believed that the natural colouring matters of butter, of which but little £&emica]l.y is known, owe their origin to chlorophyll, the colouring 'matter of green plants, together with some form of two other materials. Other chemists have made different observations with regard to the constituents of butter fat. but Dr Thorn points out . that, although the natural differences may explain to some extent the discrepancies which appear, it can hardly be doubted that they are mainly attributable' to the imperft rtion of the processes employed. He says that the fat of margarine consists mainly of glycerides of stearic, palmitic, and mvristic acids, and that it is distinct from the fat of butter by tbe absence, or practical absence, of what aao known ns volatile fatty acids, those- of relatively low molecular weiglit, and ) pric acida, which unlike the others, become more '-r less volatile, especially ii. a current ■? steam. With regard to. differences in tno physical properties of butter fat and mar-

garine, it is remarked that the former n.as invariably a higher relative density than any of the fats which are likely to be used in the process of its adulteration.