The curing of meat in this respect may be compared to the development of a cheese, except that the enzymic action in the case of meat is one of minimum extent, while in the case of cheese it is one of maximum intensity. In addition to the condimental substances above mentioned spices of different kinds are sometimes added. Vinegar is also used at times as a condimental substance and is, to a certain extent, also a preservative substance, but vinegar is chiefly used in the preservation of vegetable substances rather than meats in bulk. For meats which are spiced as well as preserved as above, vinegar is often used as one of the ingredients, intended as a condimental substance. No other substances than those mentioned above are necessary to the proper curing of meat, but convenience of application and certain other considerations have led packers of meats, when not prevented by law, to abandon the old methods to a certain extent and substitute what is known as the quick-aging process described below. =Preservation by Means of Non-condimental Chemical Preservatives.=--The use of non-condimental chemicals in the preservation of meat is practically an industry of the last quarter of a century. Up to that time the use of non-condimental chemicals was practically unknown in the meat industry. The chemicals employed are those known as germicides. In the quantities used they neither impart a taste nor odor to a preserved meat, but by their germicidal properties prevent the development of organic ferments and thus make the preservation of meat far more certain and very much less expensive. By the use of some chemicals the salting, sugaring, and smoking of preserved meats may be done with very much less care, in a very much shorter time, and at a very greatly reduced expense. For this reason the practice has gained a great vogue, not as a means of benefiting the consumers, but rather as a means of enriching the packer and dealer. Chemical preservatives are also highly objectionable because they keep meats apparently fresh, while in reality changes of the most dangerous character may be going on. They thus prevent the display of the red light danger signal.