Elements of the theory and practice of cookery

449. Death and decay are necessary to life. — On first thoughts the work of bacteria, particularly the bacteria of putrefaction, does not compare favorably with the work done by yeast. But if there were no decay, the surface of the earth would become loaded with dead matter in useless form, and after a time no plants would grow because the earth would have no food for them. You see now that we could not live Avithout bacteria. These " tiny toilers " feed upon what has been called the " broken-down remnants of things once alive," reducing them, finally, to inorganic substances suitable to be taken up by plants and again made into living matter. Thus bacteria form an invisible link between us and the dust; a link essential to the continuance of life on the globe. 450. Ways of preserving food; preservatives. — Condi- tions favorable to the growth of yeast being, in general, favorable to the growth of bacteria, a simple rule to keep the latter from troubling us is to treat them in just the opposite way from that we took to make yeast thrive and grow. That is to say, keep food cold, or dry it, or cook it. Cooking is effective for a time only, unless the food cooked be immediately sealed up so that no other bacteria can reach it. A fourth way of preserving food is to add a disinfectant (§ 59) to it if it is liquid, or to coat it with a disinfectant if it is solid. Disinfectants used on food are called preservatives. Preservatives injurious to health are often used in can- 284 THEORY AND PRACTICE OF COOKERY ning factories and by dealers in meat, milk, and other food. The process of destroying bacterial life is called ster- ilization, and anything that has undergone this process is said to be sterilized. Salt has a preservative effect on food, as has sugar, when used in large quantities. Dr. T. Mitchell Prudden has -written three interesting little books about bacteria : The Story of the Bacteria, Dust and Its Dangers, and Drinking-ivater and Ice Supplies. The last is perhaps the simplest. " The Bacteriology of Household Preserving," American Kitchen Magazine, September, 1898, is practical and helpful. Section 2. Canning and Jelly-making 451. We do well to take a lesson from the bees, and in the long summer days to store up food for the win- ter. If we can kill the bacteria in food, and then seal it up so that no more can get in, it will keep indefi- nitely. This we do in canning. CANNING 452. Can each kind of fruit in its season, when it is best and cheapest. Select it under-ripe rather than over-ripe. To insure success in preserving it observe carefully the following directions : — 453. Preparing the jars. — For a small family use pint jars. Buy jars with tight-fitting covers, and fit them each year with new rubber rings. Old rubber PLATE XIT. HI ^^^^^^^^^^Mk^^^w "^ i ^HIME~ — 9^"^ '^^^■ik IS^^^'^^^^^^^^^^B/im Filling Fruit-jars. Scales Jars Jelly-bag Measures Jelly-tuinblcr Siuicepan, with perforated wooden mat to stand Cover and ring jars upob Strainer Skimmer Funnel Paraffin Silver spoon "Wooden spoon Utensils used in Canning and Jelly-making. THE PRESERVATION OF FOOD 285