WASTE SAVING BY IMPROVEMENTS IN MILK PLANT
EQUIPMENT
.'     ;-fF-i?-';^'     ' Dr. H. A. Trebler '¦'¦¦'; J,
Chemical Engineer, Sealtest, Inc. Baltimore, Md. ;
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The wastes in the dairy industry may be classified as follows:
1. Wastes of spoiled products. These occur especially in the summer time and are mostly due to insufficient cooling facilities on the farms or insufficient plant capacity to handle the incom¬ ing milk before it sours.
2. Wastes of by-products such as whey, buttermilk or excess skim milk. These are due mostly to the fact that many plants are not yet fully equipped to utilize these valuable materials and the farmers are not always in a position to take them back to the farm for stock feed. Anyway during the period of maximum milk production the farmers may have a minimum of young stock to feed.
3. Wastes due to poorly designed or poorly maintained equipment and due to negligence or poorly trained i>ersonnel.
4. Unavoidable wastes in rinsings and wash waters from equipment. However, in a modern plant these can be kept to a minimum. In some cases these wastes may still be strong enough to require sewage disposal facilities. ,;'..;      '¦
The wastes mentioned under 1 and 2 are not due to lack of knowledge of what to do, or to a lack of profitable outlets for these products. They are due rather to lack of transportation and manu¬ facturing equipment and so a great deal of progress can be expected when the war is over. One great difficulty which the dairy industry shares with other food industries is that raw materials and most of the final products are perishable and also that there are large seasonal variations in volume. This difficulty is gradually being over¬ come to some extent by efforts to even out milk production on the farms by better winter feeding and by improved methods of manu¬ facture of dairy products of better keeping quality.
The fourth type of waste, namely the wash waters, is the most unavoidable.    However, it will be reduced in strength as progress