Gmm. Sandberg et al., THERMAL-PROCESSING CANNED MEAT WITH SUB-FREEZING INITIAL TEMPERATURES- THERMAL AND MICROBIAL VALIDATION, Journal of food science, 59(4), 1994, pp. 693
Retorting from the frozen state is attractive with respect to product
quality and economy and was investigated in canned bentonite and flake
d ham. A two dimensional finite difference model was written in which
thermal diffusivity varied with temperature. Heat penetrations were co
mpleted with initial temperatures of 0, -5 degrees, -10 degrees, -15 d
egrees and -20 degrees C. In ham, decreasing initial temperatures resu
lted in increased lag factors (j(h)) but did not affect heating rate i
ndex (f(h)). In bentonite, f(h) but not j(h) increased. D and Z of Clo
stridium sporogenes PA 3679 spores were not affected by previous freez
ing. Sub-freezing initial temperatures were judged to be consistent wi
th safe processes if validated with heat penetration studies.