Congelamento inicial da carne suína a baixas temperaturas e posterior armazenagem a -30ºC: alterações das características físicas e organolépticas .

Abstract

Pork (boned ham) was submitted to six freezing temperatures, -30, -60, -90, -120, -150 and -180° C and to three periods o f storage in freezer, 0, 90 and 180 days, under temperature o f -30° C. It was determined the kinetics of cooling and freezing and the physical and sensorial alterations. For the frozen pork to -30 and -60° C, the cooling phases, freezing and sub-freezing obtained a time of approximately, 12, 34, 44 and 10, 20, 66 minutes respectively. For the cooling phases, freezing and sub-freezing when the pork was frozen under-90 and -120° C, the obtained times were of approximately 5, 13, 45 and 5, 11, 26 respectively. When the freezing temperatures were o f -150 and -180° C, the times obtained in the cooling phases, freezing and sub-freezing were 4, 5, 40 and 3, 5, 40 respectively. pH presented a fall tendency in the 90 initial days of storage by having maintained since then and until 180 days a tendency of stabilization. The loss o f weight of the product during the storage presented an increase tendency. It can be observed that the freezing temperatures only influenced the tendency of weight loss under 180 days o f storage. The pork density in relation to the time of storage presented a discharge tendency and also it has been observed (an increase tendency) in relation to the freezing temperatures. Resistance to the fibers traction of pork presented a discharge tendency until 90 days of storage followed by a tendency to the stabilization during the rest of the storage. Pork suffered influences by the freezing temperatures on the fibers resistance. Pork softness presented a tendency to increase during the 90 days under storage, by presenting stabilization in the values during the rest of the storage. Freezing temperatures influenced pork softness. Pork appearance and flavor were neither not affected by the storage nor for the freezing temperatures. xiii