Hints on Dairying

by T. D. Curtis

CUTTING.

The coagulum should be cut as soon as it will break clean across the finger when placed in it and lifted gently upward. This early cutting is essential. There is seldom, if ever, any waste from cutting a curd too soon. The clearest whey will always be obtained by cutting early. The whey exudes from the curd much more freely when it is yet young and tender—and the only object in cutting the curd at all is to get out the whey. When cutting is begun, let it be continued as expeditiously as possible until it is finished. Do not stop and let the curd stand and toughen. It cuts more easily, with less friction and less waste by loosening fine particles of curd, when it is tender and parts easily before the knife. The more it toughens, the harder it cuts, the more friction there is, the more the curd is torn and bruised, and the more the waste. If we could cut early and cut instantaneously, it would be all the better.

CUT FINE.

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.

DRAWING THE WHEY.

We next draw the whey down to the curd—leaving enough to stir it in easily, and cool the whole mass down to 90 degrees, to avoid too much packing, and draw off the balance of the whey. The whey should be run off before the acid develops, because acid, formed from the milk in the sugar, dissolves the minerals and cuts some of the oils in the curd, and these run off in the whey. Many curds, by remaining in the whey too long, become whey-soaked, and make cheese that is soggy and hard, with a sour flavor. This kind of firmness is not desirable, notwithstanding it is called for by buyers, who seldom know anything about cheese making. If the acid develops before the whey is properly expelled, or the curd is "cooked," it carries off the minerals, which are in the form of phosphates, and this makes the cheese poor indeed. These phosphates are of lime, iron, magnesium, etc., but the principal is phosphate of lime. The affinity of these minerals for lactic acid is stronger than for phosphoric acid; so they let go of the latter and unite with the lactic acid, forming lactates and leaving the phosphoric acid free. But if we get all of the whey out of the curd that we desire, and then get the curd out of the whey—that is, draw off the whey—before the acid comes on, we retain the phosphates and fats in the cheese—all the goodness that belongs in it. The acid will come on afterward, but we have reduced the sugar to a minimum, and the amount of acid developed does no serious injury. As the whey is already expelled, of course it cannot wash out the minerals that are dissolved. These remain, and in the process of curing recombine with the phosphoric acid. We have left in the curd about 3½ parts of the 87 parts in 100 parts of milk. The whey left in the curd contains, we will say, 1-10th of the sugar that was in the milk. The acid formed from this, though too small to do any known injury, is large enough to do all the good required, if it does any good at all. We are, therefore, safe when we get the whey out of the curd and the curd out of the whey before the development of the lactic acid.

SALTING.

When the whey is well out of the curd, so as not to waste the salt, the salt may be applied and stirred in. The salt does not stop the development of acid, as is popularly supposed. When applied, it aids in keeping the curd loose. Then the curd may stand, with occasional stirring, almost any length of time for the purpose of airing and cooling, of getting rid of any bad odors, of developing flavor by oxydation from contact with the atmosphere, and of letting the acid come on. It is safest not to put the curd to press until it has a positively clean sour smell. This shows that certain chemical changes have taken place, freeing the curd of the gases generated by this process, and prevents any huffing of the cheese on the shelf in the curing room. Where cheddaring and grinding are practiced, the salt is of course applied after the curd is ground. Cheddaring is the easier and safer method, as the whey can be drawn early, and there is no danger from the acid. Salting at the rate of 2½ lbs. of salt to 1,000 lbs. of milk is the usual practice and not far from right. For long keeping, 3 lbs. of salt are not too much. Use none but the best dairy salt—the best of all the dairy salts, as well as the cheapest, being the Onondaga, F.F.