32 



EXPERIMENTS ON THE SPOILAGE OF TOMATO KETCHUP. 



as nearly as possible the treatment would be identical. The following 

 results were obtained : 



Thermal death point of moist and dry conidia of Penicillium. 



PENICILLIUM IN 10 CC OF TOMATO BOUILLON. 



PENICILLIUM IN 10 CC OF KETCHUP. 



DRY CONIDIA. 



YEAST. 



The moist heat was very effective in destroying the vitality of the 

 conidia of Penicillium, the death point being 27 C. higher than 

 the maximum temperature for germination as given by Sykes. 

 The heating was more effective in destroying germs when applied to 

 bouillon than to ketchup, no development taking place for any tem- 

 perature above 65 C., even when applied for a short time. 



In the ketchup the lower temperatures for the longer periods of 

 time were more effective in checking the development, even though 

 they did not destroy the vitality. In the ketchup, with the excep- 

 tion of Nos. 9 and 10, the colonies started invariably along the sides 

 of the flasks. The greater access of air to those on the sides would 



