If anything will prevent sour milk from making leaky cheese, it is thorough cooking. This process you should hurry up as much as possible—always having an eye to keeping the heat even, and preventing waste of butter. The acid, acting on the butter globules, makes their coatings tender. Therefore, handle the curd as carefully as possible, cool well before putting to press, and press gently, increasing the pressure gradually. But, if you have succeeded in getting your curd properly cooked, you have done one of the best things possible to retain the butter. If, when you put the curd to press, you find you have more than the usual bulk of curd, filling the hoops fuller and refusing to yield readily to the pressure of the screw—as is generally the case with sour milk, as managed in most factories—you may know that you have not done your work thoroughly, and therefore look out for leaky, sour, poor cheese. On the other hand, if you have condensed the curd to the usual bulk, so that it works well under the screw, you may hope for a fair cheese, that may pass muster when the buyer comes along.
We often hear the remark, when anything is said about developing the acid, "No sour cheese for me; I prefer to dip my curd sweet." People who talk in this way either make bitter, bad-flavored cheese, or else get on more acid than they are aware of, in consequence of having dull taste and smell. They judge by the appearance and feel of the curd when it is in condition to dip, and may succeed in hitting the right point. In hot weather, it is hardly possible not to develop the acid sufficiently. But if they really dip the curd sweet, we do not believe it possible that their cheese can be up to the standard demanded by the best markets, though they may succeed in getting a fair price for it. Not all buyers are really good judges, and fewer still know what the matter is with a cheese that is imperfectly made. They know, perhaps, that there is something wrong about it; but what, they are unable to say. Further, we believe the average price of American cheese lower than it should be, in consequence of so little really prime cheese, and of the large amount of second-rate; and that, as yet, our buyers are not sufficiently discriminating in their purchases and prices, though they are yearly growing more so. Both buyers and cheese-makers need more experience and a better understanding of what is requisite in the manufacture of a prime article.
CHAPTER XVII. DIPPING CURDS.
There is nothing so difficult in cheese-making as to determine the exact point when a curd ought to be taken out of the vat and salted. A slight variation either way from this point makes an uneven lot of cheese, and much variation spoils the batch, so that it will not pass for "prime." Every cheese-maker has felt the want of some test whereby the exact point, when a curd is sufficiently "done" to dip, can be determined with certainty. Neither the sense of smell, the sense of taste, nor the sense of touch is infallible. The evidence of this fact can be seen in any factory during the season of cheese-making. A simple test of acidity, which is claimed to be conclusive, is the application of a hot iron to a lump of curd. The iron wants to be searing hot—not red hot, but hot enough to toast cheese. Take up a small handful of curd, squeeze the whey out of it, and touch the hot iron to it, holding it there for a moment, or until it adheres and begins to melt or toast the cheese. Then pull the iron gently away from the curd. If the curd is raw and sweet, it will break short off from the iron and appear crumbly. If slightly acid, it will slightly pull out in threads, but not very long ones. As the acid develops, the stringiness increases. At a certain point, the curd will cling to the iron and pull out in numerous fine threads an inch or two long. Beyond this point, the threads grow longer but fewer, until there will be only one, which will draw out a foot or so, and then break, recoiling somewhat like India-rubber. Indeed, the curd grows tougher and more stringy from the time it begins to take on acid perceptibly, until it finally ends in stringing indefinitely, like wax, having passed the point of breaking and flying back. The successive stages of development are gradual, but very marked, and cannot fail to be recognized after a few experiments.
Thus having obtained a means of telling the degree of acid developed, it only remains to be decided at what point to dip the curd. It is claimed that the proper one is where the threads are the finest and most numerous. Beyond this point, the threads diminish in number but increase in length, which is an indication of too much acid. It is asserted that the hot iron test is uniform and reliable, besides being easy of application. Cheese-makers can make their own experiments, and we advise them to try the hot iron to their own satisfaction. If it should prove as conclusive as good judges think it will, it will be of immense value to our dairymen.
This test reminds us of the test used by maple-sugar makers to determine when the batch has reached the point where it will "grain" and "cake" well. They make a small bow of a twig, dip it into the sugar, which adheres to and fills it, and then they blow through the bow. If no bubble forms and floats off like a soap-bubble, the batch is not done. But if they can blow a string of bubbles, or one long bubble, it is time to remove the heat. The stringing of the cheese-curd, on the application of the hot iron, seems to afford a very similar test for the cheese-maker.
It is not claimed that the use of the hot iron will necessarily insure the making of good cheese. It only determines the degree of acidity, which is one very important point. Other things are requisite to the manufacture of a prime article, and the same care, attention, and labor, in other matters, will remain just as essential. By using the hot iron, however, it is claimed that the cheese-maker can tell, every time, just how sour his curd is.