MILK AND CREAM FOR FACTORY SUPPLY.

New Zealand Journal of Agriculture, Volume XX, Issue 3, 20 March 1920, Page 144

MILK AND CREAM FOR FACTORY SUPPLY.

THE PRODUCTION OF SOUND RAW MATERIAL.

G. M. VALENTINE

Dairy Instructor, Auckland.

Practically speaking, the value of dairy-produce, especially butter, is determined by its flavour and keeping-quality, and both these points are- almost entirely dependent on the state of the raw material when delivered to the factory.

It has been shown by experiment that milk drawn from a healthy cow, in perfectly clean surroundings, will keep for an indefinite period without material change if sealed up in a sterile vessel. While such conditions are not to be found on the average farm, the nearer they can be approached the better will be the condition of the milk produced. The most likely sources of contamination are dirty utensils, hands, or udders, and an impure atmosphere resulting from dirty sheds and dairies. Fully 90 per cent, of the defects in milk and cream are due to these causes, and neglect of cooling. .

In the production of high-quality milk and cream four things are necessarynamely, a good set of brushes, plenty of boiling water, a good cooler, and, lastly, the inclination to use them.

Under present-day dairying conditions, where milking - machines and separators are in everyday use, quite a number of brushes are required if all the various parts connected with these machines are to be kept ’ thoroughly clean. Without them it is impossible to get into the numerous corners where stale milk collects, with the result that each milking is inoculated by the germs which have developed since the previous one. Direct contact with dirty utensils is without doubt the most frequent cause of bad milk and cream.

The boiling-point of water at sea-level is 212 0 F., and no other temperature will do the same work. Hot water may be any temperature from just above blood-heat, which is quite suitable for washing utensils, but for scalding no temperature lower than boilingpoint will give the same results. '

The temperature at which milk is drawn from the cow is ideal for the development of the germs with which the atmosphere of even the cleanest shed is laden. By cooling the milk the growth of these germs is checked, and the development of bad flavours, which are the result of their action, is prevented.

- Of the four requirements mentioned the last is the most important, as shown by the fact that where conditions are not of the best a liberal use of the first three may result in a good' class of milk being produced. The labour entailed under such conditions is very much greater than where proper conveniences are provided, and as labour accounts for from one-third to one-half of the total cost of producing butterfat this aspect of the question cannot be ignored.