350 PHARMACEUTICAL BACTERIOLOGY 



from the camp fire, salt, brine, vinegar, wine (alcoholic beverages) and 

 sugar was noted. Thus primitive man made use of the germicidal powers 

 of sunlight, drying, dry heat, moist heat, wood ash, smoke, creosote (in 

 smoking meats), salt solutions, acids (in vinegar) and alcohol, without 

 having any idea as to why these agents retarded or prevented the decom- 

 position of organic food substances. 



In modern times the use of food preservatives is based upon the germ 

 theory of decomposition. The time-honored preservatives above referred 

 to have continued in use and many new ones have been added, as benzoic 

 acid, sodium benzoate, boracic acid, borax, saUcyHc acid, sodium sulphite, 

 sulphurous acid, formahn and many others. A somewhat generaUzed 

 theoretical assumption is that the chemical preservatives in foods are more 

 or less injurious to health. It cannot be denied that some of the preserva- 

 tives used are irritating to the kidneys and skin and some perhaps interfere 

 more or less with food digestion and assimilation. It has long been known, 

 for example, that the prolonged consumption of salted meats produces 

 serious skin affections designated as scurvy. The sulphites are irritating 

 to the kidneys; formahn interferes with digestion of foods, etc. However, 

 there can be little doubt that in the comparative sense it is far more con- 

 ducive to health and longevity to eat preserved foods than foods which are 

 more or less decomposed. We are daily making use of foods which contain 

 small quantities of natural preservatives. Cranberries, for example, con- 

 tain benzoic acid; formalin and phloroglucin are present in minute quan- 

 tities in certain plants; a multitudinous variety of salts, acids, sugars, 

 aromatic oils, etc., are present in food plants. Food chemists do not 

 appear to be seriously worried about these natural preserving agents nor 

 about the old-time artificial preservatives as smoke creosote, salt, brine, 

 sugar, and vinegar, and it is reasonable to suppose that careful investiga- 

 tion will disclose new chemical preservatives which are superior to those 

 mentioned. The whole discussion regarding artificially added chemical 

 food preservatives will no doubt simmer down to the following: What 

 is the smallest amount of the least objectionable chemical food preservatives 

 which must be added to certain food substances in order to preserve them 

 until they are to be consumed? Also the following correlative rule should 

 hold good: No chemical food preservatives whatsoever should be used as 

 such excepting in cases where modern methods of heat and cold sterilization 

 and preservation fail or are inapplicable. 



The use of sugar and of salt in moderation are, of course, always permis- 

 sible, since these substances are essentials in many foods. The objection 

 and danger in the use of food preservatives he in the fact that careless 

 manufacturers are too prone to use them in order to avoid employing 

 harmless, though perhaps less simple, and more expensive means of food 



