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Item 18r

RAW MILK COOLING

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REQUIREMENT: Raw milk for pasteurization shall be cooled to 10 C (50 F)or less
within 4 hours or less of the commencement of the first milking, and to 7 (45 F) or
less within 2 hours after the completion of milking. Provided, that the blend
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temperature after the first milking and subsequent milkings does not exceed 10 C
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(50 F).

Public Health Reason: Milk Produced by disease-free lactating animals and under
clean conditions usually contains relatively few bacteria immediately after milking.
These can multiply to enormous numbers in a few hours unless the milk is
cooled. However, when the milk is cooled quickly to 7C (45F) or less, there is
only a slow increase in the numbers of bacteria. Usually, the bacteria in milk are
harmless, and if this were always true, there would be no reason to cool milk,
except to delay souring. There is, however, no way for the dairy-operator or
regulating officer to be absolutely sure that no disease bacteria have entered the
milk, even though observance of the other items of this Ordinance will greatly
reduce this likelihood. The likelihood of transmitting disease is much increased
when the milk contains large numbers of disease bacteria. Therefore, it is
extremely important for milk to be cooled quickly, so that small numbers of
bacteria which may have entered will not multiply.

Inspectional areas of emphasis or special problem areas may be:

1. Meeting the cooling requirement may not be difficult on smaller farms milking
only twice daily with adequately sized and properly operating farm bulk tanks.
There may be cooling problems, however on those larger farms milking larger
herds on extended schedules. The practice of 3 x day milking may add to this
problem.

This is especially true on those farms which have recently expanded using the
same bulk tank and attempting to cool twice the amount of milk. The
refrigeration unit may not be capable to handle the increased load and milk
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temperatures may never attain the 45 F requirement within two hours after
milking. Therefore the NCIMS has voted to allow milk to be cooled to <50

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