EMPIRE BUTTERS

Taranaki Daily News, 23 December 1932, Page 16

EMPIRE BUTTERS

. VITAMIN STRENGTHS. EXPERIMENTS WITH RATS.. London, Nov. 17.. 1 An interesting official 1 report by the Privy Council, Medical Research Council is that dealing with the vitamin, con- 1 tent of Australian, New Zealand and English butters, states the, New Zealand Herald- correspondent. The report gives an ; account of .investigations forming part of a scheme -of ■ research into the vitamin content of foodstuffs, particularly fruit, vegetables and dairy . products,- and ■ into the effects upon. it of different methods of cultivation, preparation, transport and storage. The studies are made by Dr. S. S. Zilva - and-his assistants, working m the service of the Medical Research Council at the Lister Institute, * London, with the - valuable collaboration of’workers in the Dominions. A grant for the -cost of the work during a period of years was made to the council by the Empire Marketing Board. ■ ' ’' 1 '• , ■' ; , A standard. strain of. black and piea variety of the Norwegian rat was : used for the'investigations.’Vitamin A was estimated by a method based on Strenbock’s principle. Rats were kept on a diet free from vitamin. A but containing vitamin D, and at a stage when the bodily, reserves of vitamin A of the animals began showing signs of depletion ffie test doses, of the butters were administered. The. growth response was taken as the. chief criterion of vitamin A activity. • . For testing vitamin D the Chick, Korenchevsky and Roscoe method (1926) was employed. 1 In this method the. rats received a basal diet , low in. the . antirachitic vitamin and. in phosphorus, while the test doges are administered from the beginning of the test. The degree of calcification in the bone as determin'ed by the ; ash content is used as a criterion for vitamin D a,ctivity. . 1 . - -. : . The report gives a comprehensive de.-, scription of the preparation of the special lots of New Zealand 1 butter whiph were subjected to the tests. The lots consisted of Mangorei . butter, 1 prepared from mixed breeds, and Lepperton butter, from Jersey cows only. Tests were made with summer and winter butters, and with butters stored for a year. Controlled makes of Australian and English butters v/erC also subjected to tests.

The scientists thus summarise their conclusions, '■ . / r ~ •■_ (1) The examinations of samples of summer, butters prepared under carefully’ controlled conditions in Australia (192728, 1928-29), and in New. Zealand (192728) showed that all the samples had a vitamin A and -D content closely approaching that’ of the best' butters available from any other sources.’ , • >’ (2) There was no significant difference between the potencies: of’ the Australian butters from New South Wales,'Queensland and Victoria-respec-tively, :- ' ’- . / (3) The vitamin D. content.of samples of butter prepared in New,Zealand during the winter of 1929- was definitely lower than, that of the corresponding summer samples (of 1927-28). The results of the vitamin A tests' for butters were not decisive; but they gave ‘indication that • there ;; was, rib 'significant change due to season. './:/'• (4) The neutralisation of. acid creams before churning, such as is practised in Australia and New Zealand, has, no de-J structive effect upon the vitamin A and D content of the. resulting butters. -. . (5) There was nd - significant loss of either vitamin , A or D when butters were .in cold for a short .period —5 to' 10. iripnths-rAvhether '■ in < sjtnall .or large bulk or whether prepared. from sweet or from-: sour : cream, and New'. Zealand, butters, even , whei> stored in the cold for much longer periods—one to three years—retained ‘ most of their original- potency. 1 Definite losses in ‘vitainln A were -detected only Hn some samples, of English origin stored for, nearly two -years.' *; ■; 1 (6) No notable differences were' found between the vitamin A arid D potency qf New' Zealand butters from a-" Jersey herd and that bi-the butters from mixed in. New Zealand and Australia. The breed of 'the dairy herd seerris to have no significant influence upon the vitamin content of the,’butters. ' * '