In a factory aseptically packed tomato based vegetable soup has been sterilised by heating 13 seconds at 120 centigrade degrees. The processor detects some spoiled packages very frequently. Therefore, he would like to develop a safer heating process to obtain 1/ 20000 probability of spoilage (B. coagulans spores in tomato juice have a Do of 0.082 min and z of 10 centigrade degrees).

(a) What should be the Fo of this process to obtain 1/20000 probability of spoilage? (b) Compare the Fo values of the current and new

processes.

(c) To obtain the new Fo what should be the heating time at 120 centigrade degree ?

Fo= Do (log No - log N)

D = t/log No - log N