BACTERIOLOGICAL TREATMENT OF BUTTER.

Otago Daily Times, Issue 11642, 27 January 1900, Page 11

BACTERIOLOGICAL TREATMENT OF BUTTER.

A HIXT TO riIODUOEISS. • Paper ontitled " Bacteriological Keseareh in the Milk flora of Australia," by Mr B. J. Bull and Mr H. W. Potts, was read'yesterday in tho section devoted to economic science and agriculture. The authors of the-paper wrote that, recognising existent dairying conditions in which, the introduction of numberless organisms to the milk were provocative of tainted flavours, and retarded the keeping qualities of butter, they asked the question, ought we not to adopt pasteurisation," and the answer was yes. The principles underlying its application were readily grasped. The separator removed a large percentage of organisms, and the remainder should be.destroyed by means of the admirable pasteurisers now in use. After cooling the cream must be.impregnated with selected families ol acid-producing organisms, which set up the fermentation needed to impart the desirable ncid miUy flavour, waxy texture, and durable keeping qualities. On the purity and selection of the cultures .and their suitable treatment depended the bulter-makorV ability to provide his customer with any flavour or aroma he might demand. At many of tho factories indigenous " starters " were developed from the daily supply of buttermilk direct from the churn. Them undoubtedly gave good results, but their use was empirical i\o certainty of purity in the culture was assured. When examining buttermilk starters at the factories tiie authors had occasionally identified foreign invasions, all of which might impart to; the butter objectionable taints and flavours, or "fishiness " 4.11 . factories or butlermakers should aim at *se- ; curing a pure culture from which to make ! the starter. It was the most certain, effective, and reliable, The Department of : Agriculture imported direct from five of the principal laboratories in Europe a number of tho so-called pure cultures in powder form, and also a few from America. The«e were found unsatisfactory, and Mr Martin Secretary of Agriculture, issued instructions for the preparation and distribution of puro ST'li arf filctoiy aPP]y"'S for them. Eventually, after numerous trials, it was decided to select a special species of lactic aCKI-produeing bacteria taken from the but-ter-mitk in the Garvoc factory. Sterlised milk was treated with these cultures, and satisfactory coagulation resulted. Thirty culnti^ctuKmß^^^^^ ripened with the Garvoc pure culture was wa^ti St m r Per cwt> wllil* the bllt "wIS and which had not been submitted to nas teuruation was worth 94s per cwt. The difference ,n value therefore, wm £*. p « ton m f avoilr of the ]r . Per lOjUUU tons, the adopt on of naateiirixntinn butter producers of the colony.