Effects of Different Freezing Methods on the Quality of Braised Beef with Potato
The effects of immersion freezing and air freezing at different temperatures(-18 and-38 ℃)on the quality of braised beef with potato were studied by physicochemical measurements,microstructural observation and sensory evaluation.The results showed that freezing at-38 ℃ maintained better quality of braised beef with potato compared with freezing at-18 ℃,and immersion freezing was significantly superior to air freezing.The freezing time of beef and potato in the dish under-38 ℃ immersion freezing was shortened by 96.02％and 97.34％,respectively,compared with air freezing at-18 ℃,and the time required to pass through the maximum ice crystal formation zone for beef and potato was 9.67 and 10.92 min,respectively,suggesting improved freezing rate of the dish.Under this condition,the L*,a*and b*values of beef and potato were closer to those of the unfrozen dish;the hardness and elasticity of beef were significantly higher than those of the other frozen treatment groups(P＜0.05),and the shear force was 25.35 N,which was closer to that of the unfrozen sample(26.70 N),indicating good toughness of beef;the hardness of potato was 341.95 g,which was significantly higher than that of(P＜0.05)air-frozen samples,indicating good texture.Scanning electron microscopy(SEM)showed that beef muscle fibers were not broken after immersion freezing at-38 ℃,the gap between muscle fiber bundles was the smallest,arranged in an orderly manner;the cell contour of potato was clear and compact.The overall sensory score of the immersion-frozen sample was higher than that of the air-frozen one,and the sensory scores of beef and potato in the dish after-38 ℃ immersion freezing were 88.80 and 86.80 points,respectively,indicating higher acceptability.These findings provide a theoretical basis for the development of freezing preservation technologies for industrialized Chinese dishes.
braised beef with potatoesair freezingimmersion freezingdish quality
万方数据
维普
