MILK AND CREAM

New Zealand Herald, Volume LXXII, Issue 22225, 27 September 1935, Page 5

MILK AND CREAM

PRODUCING FINEST QUALITY EFFICIENCY OF SHED WORK INFLUENCE ON THE GRADE (From a bulletin prepared by MnsaejAcricultural College) It is the efficiency with which work is carried out in the milk.ng shod that essentially determines the grade of milk or cream. Frequently milking machines are blamed for low-grade products. It is not the milking machine which is the causo of trouble, but the carelessness of the supplier in not paying attention to the cleaning and care of the machine. Realising that dirt, cow hairs, dust and badly-washed machines and utensils, especially if damp, carry bacteria iuto milk, the supplier can, by the exercise of common senso in carrying out work in the shed, ensure the avoidance of contamination.

Before the cows enter the yard the floor should be swilled with water, since this prevents dust from rising, and also prevents the cows from slipping. If a milking machine is in use the whole plant should bo assembled and flushed out with clean cold water. The separator, ccfolcr and other equipment should be ready for use before the cows enter the yard. Cooling o! the Milk Too much attention cannot bo devoted to cooling the milk. The lack of cooling is one of the commonest causes of low-grade milk and cream. When whole milk is being supplied from tho farm, the milk should be cooled immediately after production to a temperature as low as it is possible to obtain on tho farm, and not more than 65 degrees Fahrenheit. Mere aeration of the milk is practically valueless. Chute coolers should bo provided witlr a means of passing water through the base in a flow counter-current to the milk. When milk is separated it is equally important to cool tho cream immediately it passes from the separator. The passage of the milk or cream over the cooler tends to lessen food taints by reason of tho aeration. It is most important that cooling should be carried out in an atmosphere exposed neither to dust nor to rain and wind. Washing and Sterilising

As soon as the milking process is completed, plant and utensils should be washed and sterilised. Two distinct operations are involved, namely: (a) Tho removal of all traces of milk by thorough rinsing _ of the milking machine and utensils, first with plenty of cold water, and next with warm soda water, accompanied by scrubbing with a brush when necessary; and (b) tho heat treatment of the plant and utensils either with boiling water or with steam. Where steam is available it is a good practice to wash the plant with boiling water after it has been thoroughly rinsed free of milk sclids and finally to steam it. Wherever possible utensils such as milking buckets, parts of separator, etc., should be immersed in boiling water. It is most important to remember that milk should be thoroughly washed off the metalware before tho latter comes in contact with hot water or stoam. in order to avoid a deposit of milk stone. After the milking plant and utensils have heen sterilised, they should be allowed to drain and dry in a clean, draughty atmosphere. They should not be dried with a cloth.

The milk of newly-calved cows should not be included in the factory supply till tho animals have been in profit for a week. Similarly, milk drawn from diseased quarters of udders and that from cows receiving medicine should not be included in the bulk supply. Control of Feed Taints Certain foods impart a characteristic and undesirable odour and taste to freshly-drawn milk. Such abnormal flavour can bo detected as tho milk is drawn from the cow. Some supplementary foods are liablo to produce undesirable flavours when not fed with sufficient care. Such foods include turnips, Swedes, choumoollier, green maize, millet, clover and lucerne. Certain weeds also cause bad tTiints. Land cress, water cress and penny-royal are examples. In general, food taints can be controlled by the recognition of two principles, namely:—(a) Food should be fed in moderate quantities immediately after milking, and not within four hours before milking; and (b) particular caro should bo taken to avoid bacterial contamination, which aggravates food taints. These principles can readily be applied in the case of supplementary foods, such as turnips and the like, which should be limited to about 401b. a cow a day. Such foods should preferably be wilted. In tho caso of pastures rich- in clover the problem of controlling taints is more difficult, because frequently in the spring monthp all of tho pastures on the farm are rich in rapidly-growing clover. The best the farmer can do, in tho present stato of knowledge, is to turn his cows into tho grassiest paddocks in the afternoon, so that the animals will reduce their consumption of clover to a minimum before milking.

Absorbed Flavours Butter-fat readily absorbs any odours that may pervade the atmosphere, such, for example, as the exhaust gases from an engine, smoke from q. coal fire, paint of newly-painted buildings, disinfectants used in the milking shed or on the cow's teats, and many other similar substances. The greatest care should bo taken, in the selection of substances to apply to teats and udders, to choose compounds which are neither odoriferous nor harmful in any other way.

When every care is taken to produce clean milk, sometimes peculiar flavours arise, stich as oily flavours. These aro sometimes attributable to traces of metals, particularly iron and copper, getting into the milk from milk cans, coolers and the like. As small an amount as one part per milion may cause such trouble, especially when the milk or cream is well cooled. Care should therefore bo taken to ensure that all metals used in handling tho milk should eithor not be acted upon hy milk, or be well tinned to protect the milk from being affected by tho underlying metal. In a somewhat similar way direct sunlight causes a tallowy taste in cream and milk.