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Show PASTEURIZING MILK AT LOW TEMPERATURES In ordor to dotorralno tho best way of pasteurizing milk so as to kill tho disease germs and yet not glvo the milk a cooked flavor or lessen its nutritive value, tho Department of Agriculture, through Its Dairy Division Divi-sion ,has beon conducting a series of experiments, treating milk at different dif-ferent temperatures and for different differ-ent length of time. According to tho roport on these experiments in nul-lotln nul-lotln 106 of the Bureau of Animal Industry, when milk is pasteurized at H5 degrees H. for 30 minutes the chemical changes aro so Blight that It Is unlikely that tho protein (musclo nulldlng clement) or tho phosphates of llmo and magnesia aro rendered less dlgestlblo than they aro in raw milk. Moreovor, from a bacteriological standpoint, pasteurizing at low temperatures tem-peratures Is found to bo nioro satisfactory satis-factory than pasteurizing at high temperatures. According to Hullo-tins Hullo-tins 12C and 161, whero low temperatures temper-atures aro used tho majority of bac-torla bac-torla that survlvo aro lactic acid or-Kunlsms or-Kunlsms which pluy un Important part in tho normal souring of milk. When milk Is efficiently pasteurized at high temperatures tho bacteria which survlvo aro largely of tho pu-refactlco pu-refactlco kinds, and milk so treated treat-ed If kept for any length of tlmo has a tendency to rot Instead of sour. From the standpoint of economy, tho technologist of tho Dairy Division finds that pasteurizing at low tern-neratures tern-neratures calls for loss heat. It is found that it takes about 23 1-2 per cent less boat to raise milk to tho temporaturo of 145 degrees F. than to a temperaturo of 165 degrees F. A similar gain Is n saving of tho Ico needed, becauso It will requlro 23 1-2 per cent moro refrigeration to cool inllk to tho shipping point when it Is pastourled at tho higher tompor-oturo. tompor-oturo. Tho department, thereforo, iccommends that "When market milk Is pasteurized It should bo heated to about 145 degrees F. and hold at that temperature for thirty minutes." - |