Causes Of Low Cream Grading

Northern Advocate, 22 July 1939, Page 7

Causes Of Low Cream Grading

“Could we but eliminate the small percentage of second grade cream for the manufacture of export butter, we would materially close the gap between the prices for New Zealand and Danish butter. “The people of England don't pay from Id to 3d per lb. more for Danish butter because it is Danish, but because they like it better.” These comments were made by Mr M. A. Wallace, dairy instructor to the Department of Agriculture at Whangarei, when addressing shareholders of the Maungatapere Co-op. Dairy Co., Ltd., on Thursday. Discussing various factors affecting cream grading, Mr Wallace said that of the three grades “finest grade” referred to cream which was clean in flavour, uniform in consistency, and free from other defects. “First grade” cream was almost clean in flavour, and in other respects conformed to the higher standard, while “second grade” cream was below the standard of first grade, but was suitable for the manufacture of butter. Causes of Lew Grades. Grading was carried out by means of the sense of sight, taste and smell, and the causes of low grading could be classified under the headings of bacteriological, chemical and feed flavours.

Bacteriological causes were responsible for 90 per cent of the low gradings. he continued. There might bo up to ,a few thousands of germs in one cubic centimeter of cream, and each germ, under favourable conditions, was capable of reproducing itself every half hour. Thus in 24 hours, one germ could be responsible for the growth of 17,000,000 more. Mr Wallace stressed the necessity of cream being properly cooled to prevent bacteriological development, and also of the proper care and cleaning of milking machines, plant and equipment to eliminate bacterial breeding. Chemical Flavours. Chemical flavours, he said, were duo to the presence of mineral salts in cream, and were very difficult to deal with from a factory point of view, being carried right through into the butter itself, and promoting rancidity and other defects. The flavours .arose principally from rusted surfaces in buckets, machines and plant, and also from untinned copper surfaces, which would be dissolved by the acid action of milk. Dealing with feed flavours, Mr Wallace said that the principal feeds having an undesirable effect on milk were those of the lotus group, subterranean suckling and white clover, land cross, turnips, garlic, fern bracken and wild onion. Flavour could be prevented, however. by feeding substances likely to affect the milk at least three hours prior to milking.