. Milk. Milk. MICRO-ORGANISMS IN MILK 329 milking and sampling, growth accounts for the larger part of the germs found. Accordingly, temperature control is the largest factor in controlhng germ life in city ; After testing nearly 300 samples of Chicago market milk Jor- dan and the writer found that the number of bacteria increases steadily as the seasonal temperature rises. During April the aver- age nimaber of bacteria in all samples was 9,361,000 per cubic cen- timeter, during May, which was relatively cool, 10,071,000, and during June, 18,924,000. Lewis and Wright investigated the
. Milk. Milk. MICRO-ORGANISMS IN MILK 329 milking and sampling, growth accounts for the larger part of the germs found. Accordingly, temperature control is the largest factor in controlhng germ life in city ; After testing nearly 300 samples of Chicago market milk Jor- dan and the writer found that the number of bacteria increases steadily as the seasonal temperature rises. During April the aver- age nimaber of bacteria in all samples was 9,361,000 per cubic cen- timeter, during May, which was relatively cool, 10,071,000, and during June, 18,924,000. Lewis and Wright investigated the bacterial content of cream and found that cream of days' age delivered in summer con- tained 462,600,000 bacteria per cubic centimeter, while in winter after five days the number of bacteria was 134,800,000 per cubic centimeter. These figures suffice to show the importance of keeping milk cool during transportation. Prompt cooling immediately after 1^ ijfffnirFp^Tww 1 M^ -^ fi fr y I i« ; 1 1 ] 1 . -U \ ^£. ' â =r J \. Fig. 162.âMilk-can jackets. Fig. 163.âStandard Fig. 164.âMilk- shipping jacket. can jacket. (A. H. Barber Creamery Supply Co.) production is not the only factor, but during subsequent trans- portation means must be provided for keeping the temperature low up to the time of consumption. This involves proper carry- ing to the railroad station, suitable refrigerator cars, cooling facil- ities on the delivery wagons, and, last but not least, keeping cool in the home. During transportation to the railway station the cans can be kept cool by covering them with moist jackets (Figs. 162-164), the evaporating water reducing the temperature. At the station the platforms should be enclosed, which is, unfortunately, not common (Fig. 165). On ordinary railway platforms the milk cans are exposed to the heating influence of sun and air, and if the covers are not tight dust may gain access to the inside. An inex- pensive shed would obviate these troubles in large
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Keywords: ., bookauthorheineman, bookcentury1900, bookdecade1910, bookyear1919
