Flash pasteurization

Pasteurising, however, does not kill all bacterial forms. It destroys those that propagate by fission only. It does not kill those that multiply by spores. The baneful kinds, unfortunately, are those which mainly breed by spore formation, and hence are more difficult to kill. In fact, only a sterilising temperature is sufficient for this  purpose. Herein lies a great danger. Unless pasteurised milk is rapidly cooled down to a temperature at which these spores become torpid, pasteurising is very dangerous, for there is every probability that all the beneficial bacteria will have been killed and only the baneful ones remain alive. Therefore artificial cooling processes must be used along with pasteurisation if the best results are to be obtained.