i) High temperature sterilizing:
Heat is the most reliable sanitizer especially when both temperature and time are controlled. Effective sterilization can be done by steam at 15 lbs. pressure for 15 minutes and as scalding water at 90-95 0 C for 10 minutes.
ii) Low temperature sanitizing:
Chlorine solution at 15-20 0 C containing 150-200 ppm available chlorine is used for a contact time of 1-2 minutes. The following factors should be considered in selecting a cleaning compound.
1. Its effectiveness in removing milk and other ruminants sticking on to the surface.
2. Effect on the bacteria present.
3. Effect on the equipment or material.
4. Effect on the hands, arms and clothes of workers.
5. Ease with which the compound can be prepared.
6. Cost involved.
A cleaning compound which is satisfactory for washing cans and milk pail may not be suitable for weighing scales churns or pasteurizes. It is therefore, advisable to obtain the recommendations of the manufactures regarding the types of detergent to be used for each cleaning job.