CONTROL OF MICROORGANISMS..
1) HEAT: i) High Temperature: Growth of microorganisms depends upon metabolic activities which depends upon different chemical reactions. These reactions are influence by temperature. Each organism has their cardinal temperature for their growth ie minimum,optimum, & maximum temperature. Heat is employed either at moist heat or dry heat.
Moist Heat: Moist heat kills mos by denaturation of proteins. It is more effective than dry heat because moist heat penetrates materials more rapidly than dry heat. Therefore, moist heat requires low temperature & short exposure because water molecules conducts heat better than air. Eg Clostridium botulinum are killed in 4- 20 minutes by moist heat at 120 c whereas these spores are killed in 2 hours by dry heat at same temperature.
Moist heat can be used or classified as;
- At temperature above 100c
- At temperature below 100c
- At temperature at 100c