Critical Factors for Thermal Processing of Institutional Pouches.

Institutional-sized pouches filled with whole kernel com in brine and condensed cream of celery soup were heated in a still retort. The sterilization values (F) and heat penetration parameters (j, f, f) were determined from temperature/time data as a function of the residual air in the horizontal pouches, pouch thickness, product fill, and circulation of the heating water. The F value for the soup was reduced from 11.5 to 2.5 min as the residual air in the pouch was increased to 250 ml The f value nearly doubled as a result of the insulating effect of the air layer at the upper surface of the pouch, Eliminating the circulation of the heating water between the pouch layers increased the critical dimension for heat transfer and reduced the F for the soup to 0.6 min, an unacceptable value.