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Show 1 f DAIRYING 1 VARIATIONS IN CREAM TESTS. H The lack of harmony, so often found H in the hand separator plant has many H causes; but perhaps the variation of H the cream test has strained more Hj friendly relations than any other one m trouble. If the test is increased a H few points, all well and good, but any fl decrease in test will generally make m the buttcrmakcr very long on trouble M and often short on cream. 1 "We handle our machine the same 1 every day" growl 9 the patron and H drives off muttering. But do you run Hg your machine the same every day? Is ithc condition of the milk the same every day? h An experiment carried on at the H? Kansas station demonstrated that the 1 temperature of the milk may cause .t H I variation of from 1 to 5 per cent. Milk H separated one day when drawn from Hj the cow and the next day allowed to H stand in zero temperature for some H time before separating will have con- Hj sidcrablc difference in temperature. H' The difference due to variation in H speed was found to be from 1 to 14 rcr Hj cent. With the same person turning H the separator each day, the speed will H not remain constant unless great care H is exercised. It is very probable then H that where different members of the H family turn the machine, the number H of revolutions per minute will be widc- H ly different. Vibration of the bowl H which may be caused by quick start H ing, unsteady foundation, bent bowl H spindle and various defects in scpara- H tor were found to make a variation H in test of 2 to 12 per cent. B The amount of flush water was m found to make a difference of from 1 M to 12 per cent. Flush water is gener M ally thrown into supply can regardless M of the amount. It is very evident that m even with the same operator there 1 would be a wide variation in th-i H amount of flush water used. Wher B the machine is operated by different m people from day to day one can rcad- H ily sec that there is a probability of a H very wide variation in test. H The rate of inflow also causes tests H to vary from 1 to 6 per cent. The H rate of inflow is also affected by ths temperature. The physical condition of the milk may cause a variation of from 1 to 12 per cent. Milk which has not been strained previous to separating may contain impurities in suspension such as pieces of manure, or any litter which is found in the cow barn of the average creamery .patron. These may clog the skim-milk tube, causing some of the skim-milk to pass through the cream outlet. The cream outlet or slot may become clogged with dirt, causing the cream to be very thick. The amount of acid, the milk would be considered under this point. The more acid, the more curd will be precipitated and thi quicker a layer will form around outside out-side of bowl, making the cream outlet smaller, and, therefore, producing thicker cream which becomes thicker and thicker until the separator finally is entirely clogged. The more acid and the smaller the machine the sooner the machine will clog. With all these conditions affecting the cream test, is it reasonable to suppose sup-pose that the test will remain constant from day to day? If there is only one patron who is sure that all of these conditons remain unchanged from day to day, he surely has a right to think that probably a fair and representative sample was not taken or some mistake was made in the testing. Pacific Dairy Review. |