On conditions necessary to obtain a clean milk supply and on methods of testing cows' milk in relation to standards of cleanness : report to the Sub-committee on clean milk / by S. Delépine, June 16th, 1918.
- Auguste Sheridan Delépine
- Date:
- 1918
Licence: In copyright
Credit: On conditions necessary to obtain a clean milk supply and on methods of testing cows' milk in relation to standards of cleanness : report to the Sub-committee on clean milk / by S. Delépine, June 16th, 1918. Source: Wellcome Collection.
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![(2) The keeping of fresh milk and of older milk in separate vessels. (3) The avoidance of unnecessary handling and transference from vessel to vessel. The milk of healthy cows collected cleanly in sterilized bottles at the farm general!}^ remains sweet for 48 to 72 hours, even when not refrigerated at the farm. The same is not true of milk which has been collected in ordinary milk pails, strained in bulk, cooled over an ordinary cooler, conveyed to town in an ordinary churn, mixed with other milk, separated and reconstituted, etc., etc., at a town dairy, and distributed often with gross carelessness by the milkman. Milk messed in this wav has a very short life, and in summer is often sour in less than 12 hours. 5.—Avoidance of straining through a common strainer. I think it unnecessary to insist more than I have done already upon the bad effects of straining as it is conducted at present. The improvement in the appearance of tire milk from which gross contaminations such as hahs, various fibres, bits of straw or hay, grit, etc., have been removed by straining in bulk is bought at the expense of a dissemination of bacteria which is very detrimental to the life of the milk, and may be the means of infecting a large quantity of good bj^ a small amount of bad milk. Careful milking in covered pails should reduce considerably the amount of these gross impurities, and a few unavoidaTrle hairs can be stopped at the time of milking if the milk of each cow is made to pass through a small piece of sterilized straining cloth as it enters the sterilized pail. 6.—Avoidance of cooling by methods causing large surfaces of milk to be exposed to air or to contact with extensive unsterilized surfaces. Milk collected with proper care generally contains fewer bacteria than the same milk immediately after passage over coolers of the usual type. Milk origmally clean does not keep so long after passage over an ordinary cooler as the clean milk left alone. When the milk is originally very dirty, it is probable that cooling is always advantageous, and that cooled dirty milk keeps longer than uncooled dirty milk. Tlie object of cooling is to prevent the rapid multiplication of bacteria. When the bacteria present in quite fresh milk are as fev/ as is the case when pi’oper care is taken, there is no appreciable increase in the number of bacteria during the three or fou]’ hours immediately following milking.](https://iiif.wellcomecollection.org/image/b29930303_0079.jp2/full/800%2C/0/default.jpg)
