Pasteurization
It is designed to destruct pathogenic bacteria, if any are present.
In addition, it serves a useful role in reducing the total bacterial
load and in solubilizing some of the components (proteins
and stabilizers). Both batch and continuous (high-temperature
short-time (HTST)) systems are in common use. In a batch
pasteurization system, blending of the ingredients is done in
large jacketed vats equipped with some means of heating,
usually saturated steam or hot water. The product is then
heated in the vat to at least 69 C and held for 30 min to satisfy
legal requirements for pasteurization. This is necessary for the
destruction of pathogenic bacteria. Various time–
temperature combinations can be used, depending on the
legal jurisdiction. Continuous pasteurization is usually performed
in an HTST heat exchanger following the blending
of ingredients in a large, insulated feed tank. Regulations concerning
time–temperature combinations for continuous pasteurization
usually specify a minimum temperature of 80 C
for at least 25 s.