Abstract: Method and apparatus for heat treating a fluid product, in which the product is preheated in a countercurrent heat exchange process and heated to the desired treatment temperature in a throughflow heat exchange process, wherein in the primary countercurrent heat exchanger section, a higher pressure than the atmospheric pressure prevails, and both in normal operation and during recirculation through the final-temperature heating section, the secondary countercurrent heat exchange section is maintained at a higher pressure than the pressure in the primary countercurrent heat exchanger section, whilst, should the pressure difference between the primary and the secondary countercurrent heat exchanger sections drop out, the supply and discharge of the product are stopped and the product to be treated is recirculated through the final-temperature heating section.

Abstract: Bacteria cultures for use as an inoculant in the preparation of starters and fermented milk products are produced by culturing a milk sugar fermenting bacteria on a culture medium containing whey, a non-whey protein in an amount of about 0.1 to 0.5 weight percent and a buffer mixture. After culturing, the bacteria may be concentrated and freeze dried to produce a starter culture concentrate which can be added directly to cheese milk. When preparing the culture medium, the whey and non-whey protein are pasteurized separately.