reatest amount of soluble nitrogenous products
are to be found in the innermost part of the cheese, a condition that is
not reconcilable with the view that the most active ripening is on the
exterior.[192]

The course of development of bacteria in cheddar cheese is materially
influenced by the ripening temperature. In cheese ripened at relatively
low temperatures (50 deg.-55 deg. F.),[193] a high germ content is
maintained for a much longer period of time than at higher temperatures.
Under these conditions the lactic-acid type continues in the ascendancy
as usual. In cheese cured at high temperatures (80 deg.-86 deg. F.) the
number of organisms is greatly diminished, and they fail to persist in
appreciable numbers for as long a time as in cheese cured at temperatures
more frequently employed.

~Influence of temperature on curing.~ Temperature exerts a most potent
influence on the quality of the cheese, as determined not only by the
rate of ripening but the nature of the process itself. Much of the poor
quality of cheese is attributable to the effect of improper curing
conditions. Probably in the initial stage of this industry cheese were
allowed to ripen without any sort of control, with the inevitable result
that during the summer months the temperature generally fluctuated so
much as to impair seriously the quality. The effect of high temperatures
(70 deg. F. and above) is to produce a rapid curing, and, therefore, a
short lived cheese; also a sharp, strong flavor, and generally a more or
less open texture. Unless the cheese is made from the best quality of
milk, it is very apt to undergo abnormal fermentations, more especially
those of a gassy character.

[Illustration: FIG. 31. Influence of curing temperature on texture of
cheese. Upper row ripened eight months at 60 deg. F.; lower row at 40
deg. F.]

Where cheese is ripened at low temperatures, ranging from 50 deg. F. down
to nearly the freezing temperatures, it is found that the quality is
greatly improved.[194] Such cheese are thoroughly broken down from a
physical point of view even though they may not show such a high per
cent of soluble nitrogenous products. They have an excellent texture,
generally solid and firm, free from all tendency to openness; and,
moreover, their flavor is clean and entirely devoid of the sharp,
undesirable tang that so frequently appears in old cheese. The keeping
quality of such cheese is much superior to the ordinary product. Th