Page:Popular Science Monthly Volume 80.djvu/408

404 largely depended upon to render harmless any disease-producing germs that may be contained in our food. While this is true of bacteria it is not true of all the products formed by them. Certain ptomaines and toxins may be destroyed by heat. Others are not susceptible to its influence. Therefore heat as employed in the process of cooking can not be regarded as a safeguard against ptomaine poisoning. Moreover it is often after cooking that these poisons are formed. Many of our cooked foods constitute the very best kind of culture media and as a result putrefactive changes may take place in them very rapidly. The safe plan is therefore to eat food soon after cooking or if it is reserved for any length of time it should be well protected from bacterial invasion and kept at a low temperature.

Cleanliness and low temperature afford the best means at our command for preserving foods from bacterial action—cleanliness to prevent the presence and contaminating influence of the millions of bacteria, often of the putrefactive type, which are always to be found where dirt and filth of any kind is allowed to accumulate and where flies and other insects are given free access, and low temperature to prevent the multiplication of those already in the food, no matter how careful we may have been to exclude them. Cold, even a freezing temperature, is not fatal to bacteria, but it does decidedly retard their growth. Even at the temperature of the ordinary refrigerator (about 10° C. or 40° F.) we find that most organisms multiply very slowly and as a result putrefactive changes are much retarded. Refrigeration is therefore a necessity for the proper keeping of foods, at least during the hot season. But to be efficient the refrigerator must be properly managed. Unless it be kept clean, properly ventilated and well supplied with ice it is practically useless, in fact absolutely dangerous.

Public sentiment is now demanding that those who produce and handle our foods should furnish them to us in a pure and wholesome condition and sanitary officials on every hand are endeavoring to enforce the proper regulation and protection of our food supply. This effort is most commendable. It is well to remember, however, that official regulation can extend only to our doors and to be fully effective it must be supplemented by proper management in our homes and in all places where food is consumed.

In conclusion, we must admit that well-defined cases of ptomaine poisoning are comparatively of rare occurrence when we consider the amount of food consumed and the number of consumers. They would indeed be exceedingly rare if those who are charged with the preparation and handling of our foods would always exercise the proper precautions along the lines we have indicated.