Cut the curd very fine. Seldom, if ever, is a curd cut too fine. As
the object is to get rid of the whey, the finer it is cut, the more
easily we achieve our object. It is not as far from the center of a
small piece of curd for the whey to run out as it is from the center
of a large piece. By cutting fine, we expose more surface for the whey
to run out of, and we have smaller pieces to heat up. Curd is a bad
conductor of heat. If the pieces are large, it takes a long time for
the heat to slowly penetrate them when we want to increase it. The
small pieces, therefore, absorb the heat more evenly, and this gives an
evener action of the rennet.
"COOKING."
After the cutting is done, if the whey is separating rapidly, the heat
may be started at once. If the action of the rennet is rather slow,
it is better to wait a few minutes for the curd to harden a little,
while with your hand you carefully rub down the side of the vat, thus
removing all the curd that may be adhering to it. Not over five minutes
waiting, as a usual thing, is necessary, and generally there need be
no waiting. But as soon as the heat is started, begin to gently stir
the curd with a rake, by passing it down into the middle of the vat
and gently raising the curd on each side. If uncut pieces appear,
carefully separate them with the teeth of the rake. Keep up this
stirring, which may be more violent after the curd hardens, until the
whole is heated up to 98 or 100 degrees--or to blood heat. The reason
for constant agitation is to keep an even temperature throughout the
mass and prevent the curd from packing. This secures even action of
the rennet. The reason for going to blood heat is because rennet is
most active at this point. It is the temperature indicated by Nature.
It is the one at which we digest our food, and the one at which the
calf's stomach forms curd and afterwards digests it. The pepsin or
gastric juice is more potent at blood heat, and this pepsin or rennet
is what does the work. The heat does not cook the curd in the vat any
more than it cooks the milk in the cow's udder. We choose 98 degrees
as the proper temperature because the digestive or cheesing process of
the rennet goes on faster at this point. To go above or below it is to
lose instead of gain. This temperature should therefore be maintained
until the curd is "cooked"--that is, until the action of the rennet has
expelled the proper amount of whey and the curd is as firm as we want
it. Anent the stirring of curds, use the hands as little as possible.
There is nothing better for this purpose than the common hay rake with
the handle shortened and one tooth cut off from each end by severing
the rake-head within three quarters of an inch of the next tooth.