There are two practical and effective methods of purifying
wash-water, viz., (1) Filtration, and (2) Pasteurization. Which
of these two methods is the most practicable and the most
effective in the creamery depends upon the conditions and
upon the quality of the water. In the case of water from deep
wells, which contains little or no organic matter, but at the
same time is infested with undesirable germs, pasteurization
is perhaps more expedient. Filtration, if the same degree of
thoroughness is to be reached as in pasteurization, is a com-
paratively slow process. Pasteurization of wash-water is a
trifle more expensive than filtration. Wash-water can be
pasteurized at the same time that the churning is being done,
thus economizing in time and fuel. Pasteurization is quite
effective in rendering the water germ-free, but it is not so
effective in removing any organic matter or other tangible
impurities which may be present. If the creamery does not
already have a pasteurizer, filtration can be employed very
profitably, and under average conditions it will perhaps give
the best results.
