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acid even from mess to mess by an olfactory measurement. On March and the first half of April stock I do not care for any acid to show, but on later April and beginning of May goods acid should show on the hot iron clearly and perceptibly. When the curd is pressed to the metal, fine strings should just start from it immediately prior to salting. At this time you want just a little acid but not too much—too much will surely spoil spring made cheese.
The question arises, "How far must a cheese maker probe into the hidden mysteries that shroud the digestive assimilation of the product he manufactures?" We answer that he cannot probe too deeply or extend his researches too far into the minute. There are too many makers now with only a superficial knowledge of their craft, and before there can be any perceptible elevation of quality in American cheese the shoes of these novices must be filled by such men as we now term "experts." Take, for example, the subject of acid which we are here discussing. A maker who can preceive it only as it is revealed by stringing on the iron is not competent to be in charge of a factory, for anybody could detect it there. The development of lactic acid is a species of fermentation induced by the spontaneous increase of inherent minute bacteria. It takes the same experience to perceive and govern it in milk and cheese as it does practice with square and compass to become a carpenter. We cannot tell you all about it—it will take many days of careful observation and fine testing to understand its nature enough to make it your servant in the cheese making art. That is why makers without practical experience are always incompetent. Hold curd in the whey until it shows at least a quarter of an inch of acid by the hot iron and then draw off whey as quickly as possible. It is always a good plan where you have large vats and they are pretty well filled to have a third of the whey drawn off before acid develops, for then you can more quickly lay bare your
