Hand-book on cheese making

by George E. Newell

COAGULATION OF MILK.

If the milk you have in your vat is mature, or, in other words, slightly tending toward sour, heat it as rapidly as possible when preparing for the application of rennet. In the cool extremes of the season heat milk to 86° Fahrenheit and in warm weather to 85° before rennet is applied. If the milk is all right as to sweetness, as the bulk of milk is, heat it up to the desired point gradually, stirring it gently at frequent intervals with a long-handled dipper. You stir for the purpose of keeping down the cream and evenly distributing the warmth that is permeating the lacteal mass. You stir it with great gentleness and care because milk globules are eggs in miniature, and, like their large relatives of biped production, they must be handled with care. If you wish to heat to 85° and have an under-heater vat or fire flue beneath the milk, withdraw the fire before it has quite reached that point, as the after warmth will carry it up a degree or two. Be perfectly precise in all such little points, for on them hinge big results.

With milk in normal condition as to maturity, standing at a temperature of 85° in both ends of the vat, and with no cream visible on the surface, you are ready to take another step in the course of manufacture. If colored cheese are desired, now apply annottoine sufficient to give a rich, golden hue. Know exactly by experiment its strength as a dye, always know the quantity of milk to a pound and portion out accordingly. Work the coloring into the fluid with the same gentleness with which you have heretofore manipulated it while raising the temperature. When the milk is all of one even, yellow tinge, attesting that the annotto is represented equally in every part, it is ready for the real inceptor of cheese, rennet. The tendency of modern cheese making is toward quick coagulation of milk. The larger infusion of rennet necessary for this purpose begets cheese that can be quickly cured for a market where they are expected to be soon consumed. The old rule of coagulation in twenty minutes is now nearly obsolete, although it will always hold good for cheese of long keeping qualities. Fall made cheese that are expected to be consumed during the winter months should be strengthened for age by coagulation in from fifteen to eighteen minutes. When we are dealing with the average spring and summer make, trade demands more perishable stock and we must cater to it. If you do not know the strength of your rennet and you want the milk to thicken in eight or nine minutes, as it should do, previously test the lactic juice by putting a teaspoonful into a tumbler of milk kept warm at 85°. If the glass of fluid thickens in five minutes, you need one quart of such rennet juice for every 800 pounds of milk to effect coagulation, as stated above. If the tested quantity thickens in less or longer time, a proportionate less or greater amount is required for your purpose. Measure the rennet extract with exactness, so that there will be no miss in its proper adjustment to the milk, and then incorporate it into the vat of lacteal fluid. In infusing it into the milk structure, manipulate your dipper with the same caution that has characterized your former attitude toward the fragilely constructed fluid under your hand. After stirring for five minutes, withdraw the dipper and let the surface of the milk come to a calm. Then pass the bottom of the empty dipper lightly over the vat to drive back any particles of cream that may be struggling to the surface. The milk will soon begin to roll up in the wake of the tin utensil in your hand in a rapidly thickening wave. Immediately withdraw the dipper, for the rennet has accomplished its mission. Turning to your vat cover, stretch it tightly over the fermenting milk. The cover mentioned should consist of a strip of canvas cloth or sheeting running the entire length of the vat and lapping slightly over its width. The cloth should be tacked to lath or other light wooden strips the width of the vat, and these supports should be about two feet apart. When not in use, the cover can be rolled up like a section of carpeting and is not at all awkward to handle. Place the cover in a closed form on one end of the vat, and, unrolling it as fast as you walk, you can stretch it to the other end in half a minute, thus keeping your milk snug and close. I prefer to use such a cover every day during the season, and they are indispensable in spring and fall. Without some such device the crust of the rapidly forming curd is chilled, retarding the action of the rennet, and the temperature of the whole mass is perceptibly lowered, which is not only undesirable but positively detrimental to the natural and perfect formation of cheese.

In the course of twenty or thirty minutes after coagulation examine your crude cheese material and see if it is ready to cut up. Thrust the forefinger into the mass, and if the curd will split cleanly in front of it, it is ready for the knives. Milk should stand about forty-five minutes after the infusion of rennet before it is cut, but if the milk is very mature in quality rennet will act on the caseine more spontaneously. It may be firm enough to cut before that time; if, in such a case, the same amount of rennet had previously acted slowly on a proportionate quantity of milk, you can at once consider the quick action as a fair warning from nature that you must scald your curd in haste to keep ahead of the swiftly multiplying acid germs. As previously stated, as soon as the curd mass will cleave brittlely over the finger prepare your knives. First pick up the one with horizontal blade and hold it a second in hot water. This will warm the steel so that it will not chill the curd. Cut the mass lengthwise, turning corners deftly without lifting the instrument once until you are through. Then lay this knife aside for its work is done. Insert the perpendicular knife also in hot water and with it cut the curd first crosswise, then lengthwise, then crosswise again, being sure to lap over the course of each cut. The curd is now in small cubes that are fast discharging whey from their severed cellular system. They gravitate toward the bottom of the vat. If the curd has been cleft by the blades, gently and with great care, the rising whey has a clear, greenish cast, attesting that it is freed from most of the albuminous substances of the milk and will render a good ratio to the patrons.