BACTERIAL FOOD POISONS 141 



From the foregoing it becomes evident that careful 

 inspection of all food stuffs is necessary, together with 

 such storing and preparation as will keep them in whole- 

 some condition. Where proper storage facilities exist 

 (i. e., large cold-storage plants), in which edibles are 

 kept at a constantly low temperature, meat, fish, eggs, 

 fruit, etc., can be kept in good condition for months. 

 In the absence of such facilities, perishable foods must 

 be freshly consumed. In warm weather it is not safe 

 to keep fish for more than twenty-four hours. In the 

 home foods must be kept in the refrigerator. While 

 bacterial growth at refrigerator temperature is very 

 slow, it is not entirely inhibited, and for this reason the 

 ice-chest must be kept very clean. It is especially im- 

 portant that food spilled on the shelves be immediately 

 removed; the ice-box should be washed from time to 

 time with a solution of soda in hot water and quickly 

 cooled again; at all times it should be kept well filled 

 with ice. The fluctuations of temperature due to insuf- 

 ficient ice supply are especially harmful. 



From what has been said elsewhere of the habits of 

 the house-fly, it follows that no food must be allowed to 

 stand around in uncovered vessels. Food which is at all 

 suspicious as to color or odor should be discarded, and all 

 foods which are not perfectly fresh including canned 

 fruits and vegetables should be thoroughly cooked 

 before eating. 



When bacterial decomposition has taken place in 

 canned food the tops of the cans may present a convex 

 surface, making what is known as a "blown" can or a 

 "swelled head." The contents of a "blown" can should, 

 therefore, never be used for food. 



