erable one, but the quality of the factory
by-product for feeding purposes, whether it is skim-milk or whey, is
impaired through the development of fermentative changes.

[Illustration: FIG. 7. Swiss cheese factory (Wisconsin), showing
careless way in which whey is handled. Each patron's share is placed in
a barrel, from which it is removed by him. No attempt is made to cleanse
these receptacles.]

~Improved methods of disposal of by-products.~ The difficulties which
attend the distribution of these factory by-products have led to
different methods of solution. One is to use another separate set of
receptacles to carry back these products to the farm. This method has
been tried, and while it is deemed impracticable by many to handle two
sets of vessels, yet some of the most progressive factories report
excellent results where this method is in use.

Large barrels could be used for this purpose to economize in wagon
space.

Another method that has met with wider acceptance, especially in
creameries, is the custom of pasteurizing or scalding the skim-milk
immediately after it is separated, so that it is returned to the farmer
in a hot condition. In factories where the whole milk is pasteurized,
further treatment of the by-product is not necessary. In most factories
steam, generally exhaust, is used directly in the milk, and experience
has shown that such milk, without any cooling, will keep sweet for a
considerable number of hours longer than the untreated product. It is
noteworthy that the most advanced and progressive factories are the ones
that appreciate the value of this work, and although it involves some
time and expense, experience has shown the utility of the process in
that a better grade of milk is furnished by the patrons of factories
which follow this practice.[4] The exclusion of all danger of animal or
human disease is also possible in this way.

~Cleaning dairy utensils.~ The thorough cleaning of all dairy apparatus
that in any way comes in contact with the milk is one of the most
fundamental and important problems in dairying. All such apparatus
should be so constructed as to permit of easy cleaning. Tinware,
preferably of the pressed variety, gives the best surface for this
purpose and is best suited for the handling of milk.

Milk vessels should never be allowed to become dry when dirty, for dried
particles of milk residue are extremely difficult to remove. In cleaning
dairy utensils they should