Quality Butter

Manawatu Times, Volume 62, Issue 25, 30 January 1937, Page 12 (Supplement)

Quality Butter

TECHNIQUE IN THE SHED DANGER OF BACTERIA Mr W. Percival Levy of Auckland Writes: I read with concern the decision given by Mr J. H. Salmon, S.M., in the Waverley Court permitting a supplier to change from one dairy factory to another. This is, in my opinion, a very serious matter as the whole industry in the future will be so greatly affected by the quality of our production. It is a tragedy that so little is realised by the vast numbers engaged in the dairying industry to-day, from the production to the manufacturing, of the vital importance of a rigid enforcement of a dairy shed hygiene technique. I do not for one moment wish to imply that those engaged in the industry are careless and dirty, but they are ignorant of the cause and effect of our pres-ent-day methods. The time will como when a different standard of both inilk and cream grading will be inaugurated, when grading will be done on the organism or bacteria content of both milk and cream and to reach the standard required a dairy shed hygiene technique will be enforced. No butter maker can make a high quality butter from a low quality cream. An Interesting Experience Thousands of our producers are willing and anxious to produce the highest quality cream possible, but ignorance of the vital part played by these tiny organisms (bacteria) is preventing them from doing so. My own experience was precisely the same. I was milking over 200 cows and had sheds and equipment of the latest design and anyone accusing mo of producing an inferior quality cream was ridiculed. When my cream was graded low I blamed everybody but myself. I even went so far as to threaten to take my supply to another factory. The company 1 was supplying scut an inspector to inspect my sheds auS found everything in first-class order, and could find no reason why my cream should not be finest. Not until I commenced supplying fresh milk to the city did 1 find that there was something radically wrong at the producing end. Consistently, 1 was finding that a portion of both morning and evening milk would not remain fresh for more than 12 hours, and yet 70 per cent. w r ould be quite fresh at 18 to 24 hours. This position to me seemed impossible. For a long time I would not agree that there was any difference between one can of milk and another, but so persistent was this trouble that I had to investigate it. Source of the Trouble. It was found that certain cans contained many thousands of bacteria more than did the others. Following these cans through by identifying them, it was found that the trouble was with the first few cans off the machines. What was happening after each milking was the machines would be sluiced with cold water then hot water. This hot water left the milk lines at such a temperature as to start an incubation of bacteria. This propagation would go on until next milking, when with the first cows being milked, the milk line of the machine would be flushed. Such flushing would carry the bulk of the bacteria into the llrst can or so, and suited in causing the milk to sour in a very few hours. Tho milk that followed would have anything from 12 to 20 hours longer life than the first from the machines. This is tho foundation of our trouble right throughout the dairy industry to-day. Stages of Incubation. For cream production the technique is even more important than fresh milk as the cream is held longer before delivery to the factory, during which time propagation of bacteria is going on apace until checked at the manufacturing end. Actually there are two stages of incubation of bacteria after every milking. One is by leaving the milk line in a perfect state of incubation by the sluicing with hot water, the other is in the vat during milking. Tho milk held iu the vat has a temperaturo of between 92 and 94 degrees, perfect incubation heat. At this temperature one bacterium will multiply at the rate of 72,000,000 in 24 hours. This milk is then x } nt through the separator and the temperature of the cream from the separator is approximately 90 degrees, still at a perfect incubation heat. This cream goes into the can in solid fat form, thus retaining its temperature for a long period, during which time our enemy bacterium is propagating at a terrific rate. How to Fight Bacteria.

The only way to prevent this daily crop of contamination in our milk and cream is to make the conditions impossible for bacteria to live in, and this can only be done by a daily hygienic routine, as follows: First, all equipment is rinsed in cold water to remove all casein from utensils, then with an ample supply of hot water, and then, the most important, a supply of wet steam to kill all living organisms which are still adherent to all equipment. If this is done the milk from the subsequent milking will be comparatively free from contamination. The cream then should be cooled to a temperature to prevent any bacteria from propagating. At a temperature of between 60 and 65 degrees such propagation is negligible. Cream treated in this manner will, if graded correctly (feedy flavour excepted) receive a grading higher than was ever hitherto thought of. Keeping Quality in Milk.

In conclusion, I can at this moment give a very vivid example of what effect a high standard of dairy shed hygiene cau produce. My milkman has supplied us for the past six years and during the summer months we had difficulty in keeping milk for 24 hours. Some three months ago a steam steriliser was installed in his dairy shed and immediately tho effect was evident. At the moment a cup of milk stands in my cupboard from the evening milking of Thursday last. It is now 10 p.m. Sunday, approximately 77 hours old and is still perfectly sweet. This is only one of many hundreds ' of similar illustrations I have had during my investigation of this very ini-

portant subject, ami the fact of allowing a supplier to change his supply on account of not being satisfied with the grading he is receiving fills me with horror as to what such an action can lead to. Graders will become nervous of losing their supply if they grade low: borderline cream will gc* the benefit of the doubt, and as a result the manufactured article must suffer. The only way to prove that a supplier's cream is not up to standard is to take a bacteria count test. Let him contest his grievance on that test and I venture to say there would be very few suppliers who could justify the right to leave the factory they are supplying.