How do you turn a shotgun into a precision rifle - significant heat savings through the use of kinetic laboratory data (D/z values) in large-scale pasteurization

Pasteurization of bottles and cans is an important technique for biological stabilization of beer as well as mixed beer drinks, malt beer and non-alcoholic beers. Despite recuperation, the heat requirement is very high and can be significantly reduced by lowering the maximum temperature in the pasteurizer. The current practice of calculating the lethal heat effect is based on the so-called beer formula using a globalized z-value for the temperature dependence of the inactivation. The premise experiments here is that for products containing sugar, such as malt beer, yeast cells pose the greatest danger. Therefore, the D values at various temperatures and the z values of three of the Krombacher Brewery's own yeasts (bottom-fermenting and top-fermenting) were determined in the laboratory using the capillary method. In a challenge test in the brewery, bottles with different products were inoculated with these yeasts and samples were taken from the industrial pasteurizer every two minutes and examined for viable cell counts. Accordingly, using specific D/z values, precise pasteurization can be achieved, the treatment temperature can be reduced to 55° C and 20-25% of energy can be saved.