OLIVEIRA, José Divânio Pereira de.; http://lattes.cnpq.br/3396377260312903; OLIVEIRA, José Divânio Pereira de.
Resumo:
Frozen meat consumption has increased especially in large cities, calling for more
exhaustive rescarch concerning the freezing process and its influence on consumer
products. The main objective of present study is to determine the freezing kinetics and
evaluate the physical and chemical changes that occur in the lamb loin and goat meat.
Both the lamb loin and goat meat were exposed to four freezing temperatures, -22.5 and -
45 C (freezer trade), -170 C (liquid nitrogen vapor) and -196 ° C (immersion in liquid
nitrogen). A physical-chemical water content analysis, including pH, acidity, ash and
protein content was conducted in conformity with the Instituto Adolfo Lutz's, norms
whereas for texture attributes of fiber rupture and resistance, samples cutting were done in
brand texturometer TA . XT plus. The lamb loin -22.5 and -45 ° C froze faster than the
goat meat , whose times were equal to 10200 and 10800 / 2, 6240 and 6480 / 2,
respectively. At temperatures of -170 and -196 °C, the loin meat exhibited a slight
difference in freezing weather, with freezing goat meat quickly, in about 1920 / 2, in
relation to lamb, which was 1940 / 2 and 120 125 seconds, respectively. The mean effective
diffusivities (am) of loin meat goats and sheep tended to increase with decreasing freezing
temperature. The highest values of water content, pH, acidity and protein loin of goat meat
were equal to 76.8447% (-45 ° C) 5.756 (-45 ° C), 5.733 (-90 C) and 5.770 (-196 ° C),
0.052% (-90 C) and 23.490% (-170 ° C), respectively. While the lower water content, pH,
acidity and protein were equal to 71.6773% (-90 C), 5.530 (-22.5 C), 0.032% (-170 ° C) and
18.390 (-196 degrees C), respectively. On the back of the goat meat, the highest and lowest
values for water content were equal to 77.6433 (-22.5 C) and 70, 5390 (-90 C), pH equal to
5.753 (-196 ° C) and 5.610 (-22.5 °); acidity equal to 0.047, 0.045, 0.044% (-22.5, -45 and -
170 ° C) and 0.040 (-196 ° C), protein equal to 20.643 and 20.953% (-45 and -90 C) and
18.923 and 18.720 (-22.5 and - 170 ° C), while the ash did not change significantly. The
reduction of the freezing temperature gave a trend of cutting force and rupture of the fibers
of the loin of lamb and goat meat.