EXPERIMENTS WITHOUT USE OF PRESERVATIVES. 



19 



the kitchen, one in the incubator, and one in the porch, making a 

 total of 108 bottles. The average number of days for those kept in 

 the incubator was four, the minimum two, and the maximum six. 

 The average number of days before spoilage in the kitchen was five, 

 the minimum being three arid the maximum nine. Those kept in 

 the porch gave an average of twenty-three days, the minimum num- 

 ber being eighteen days and the maximum seventy- three days. 

 Thus it is seen that the ketchup lasted nearly five times as long at a 

 temperature of 30 to 60 F. as it did at 72; and also that when 

 ketchup is kept in a warm place before opening, spoilage occurs 

 somewhat sooner, the average for the fresh samples opened under 

 the same conditions being one day more with the incubator and 

 kitchen samples and four days more witli the porch samples. 



A third set of bottles of the ketchup was opened on June 6, 1908, 

 or two hundred and sixty-five days after manufacture. They had 

 been kept in a basement at a temperature of about 70 F. 



One set was placed in the incubator at a temperature of 95 F., one 

 set in the kitchen at about 82 F,, and one set in the refrigerator at 

 46 F. The weather was warm and the conditions favorable to the 

 spoilage of fresh foods. The minimum time for spoilage in the incu- 

 bator was two days, the maximum time four days, and the average 

 time three and two-tenths days. The minimum time in the kitchen 

 was two days, the maximum time six days, and the average time 

 four and four-tenths days. The minimum time in the refrigerator 

 was nine days, the maximum time nineteen days, and the average 

 time thirteen and sixty-six one-hundredths days. 



These data are grouped in the following table for easier comparison: 



Time of spoilage of ketchup at different temperatures after opening. 



OPENED ON NOVEMBER 5, 1907, IMMEDIATELY UPON RECEIPT FROM FACTORY; 

 MAXIMUM AGE, FIVE WEEKS. 



KEPT AT 70 F. FOR ONE HUNDRED AND FIFTY DAYS BEFORE OPENING ON 



FEBRUARY 11. 



Incubator. 

 Kitchen . . . 

 Porch . . . 



23 



2 

 3 



is 



73 



KEPT AT 70 F. FOR TWO HUNDRED AND SIXTY-FIVE DAYS BEFORE OPENING ON 



JUNE 6. 



