ASEPSIS A495 
Group I. Proteins (Acids and carbohydrates in traees). 
Example: Meat, fish and eggs. 
Group II. Carbohydrates (Acids and proteins in traces). 
Example: Starch, sugar, honey. 
Group III. Proteins-+Carbohydrates (Acid in traces). 
Example: Milk, cereals, flour, greens (cabbage), vege- 
tables. 
Group IV. Acids (Proteins and carbohydrates in traces). 
Example: Vinegar. 
Group V. Acid+Proteins (Carbohydrates in traces). 
Example: Hard cheese, sauerkraut. 
Group VI. Acid+Carbohydrate (Protein in traces). 
Example: Must. 
Group VII. Acid+Protein-+ Carbohydrate. 
Example: Sour milk, butter, fruit. 
Group VIII. Acids, carbohydrates and proteins in traces. 
Example: Water. 
As Rahn points out the type of decomposition in each group is quite 
sharply defined. The decomposition of foods in Group I is a typical 
putrefaction (Faulnis). The foods under Group II contain too little 
water to permit of microbial cleavage. Acid fermentations are the 
types of change for Group ITI. 
Foop PRESERVATION 
Asepsis. According to Rahn’s system the following groups of food 
substances may be preserved by asepsis. 
Group I. Meat, fish, eggs. 
Group III. Milk, vegetables, nuts. 
Group VII. Fruits. 
By asepsis is meant the prevention of contamination of food sub- 
stances by undesirable microorganisms during their preparation. The 
following factors influence this method of food preservation. 
I. Conditions of production. 
II. Amount of moisture. 
III. Physical structure. 
IV. Chemical composition. 
V. Temperature. 
Few foods are produced absolutely free from microorganisms. If 
such were the case, they would keep indefinitely. Since this is prac- 
tically impossible, it has become necessary to reduce to a minimum 
