乳酸对不同年龄秦川牛肉的嫩化效果

Studies on the tender effects of lactic acid on Qin-chuan beef at different ages

【目的】研究不同浓度乳酸对不同年龄秦川牛肉的嫩化效果,以筛选适宜的乳酸处理浓度。【方法】以剪切力为指标,研究不同浓度(0(CK),0.1,0.2,0.3,0.4和0.5 mol/L)乳酸按质量分数10%用量注射入肉样并于4℃放置1 d后,对不同年龄段(2.0,3.5和5.0岁)秦川牛肉的嫩化效果;通过石蜡切片观察,探讨乳酸对牛肉纤维结构的影响及其与牛肉嫩化效果的关系。【结果】随着乳酸浓度上升,不同年龄段秦川牛肉样的剪切力和pH值均逐渐下降,其中0.3 mol/L乳酸溶液对2.0岁秦川牛肉的嫩化效果较好(P<0.05),0.4 mol/L乳酸溶液对3.5和5.0岁秦川牛肉的嫩化效果较好(P<0.05);与对照相比,用乳酸处理后,牛肉肌纤维直径无显著(P>0.05)变化,肌纤维间隙显著(P<0.05)增大,剪切力显著(P<0.05)降低。【结论】乳酸能显著改善各年龄段秦川牛肉的嫩度,肌原纤维间隙也可作为衡量牛肉嫩化效果的指标。

[Objective] The effects of different concentrations of lactic acid on the tenderness of Qin- chuan beef were studied to select the best method on tenderness. [Method] In this study,beef of different ages （2.0 years,3.5 years and 5.0 years） was tenderized by injecting different concentrations of the lactic acid solution （0（CK）,0.1,0.2, 0.3, 0.4 and 0.5 mol/L）,and after that stored for 1 d at 4 ℃. Then the beef was subject to shearing force measurement and histological observations. [Result] High concentration of lactic acid decreased the shearing force and pH of beef. The lactic acid （0.3 tool/L） injection improved significantly the tenderness of 2-year-old beef （P〈0.05）, and lactic acid （0.4 tool/L） injection improved significantly the tenderness of 3.5-year and 5-year-old beef （P〈0.05）. The muscle fibrils gap result was the same to the shearing force,so it was possible to make the muscle fibrils gap as tender index. [Conclu- sion] The lactic acid injection improved significantly the tenderness of Qin-chuan beef at different ages. It is possible to make the muscle fibrils gap as tender index.