解冻方式对调理猪肉饼品质的影响

为探索不同解冻方式对猪肉饼品质和蛋白质氧化程度的影响,本试验将-18℃冻藏的调理猪肉饼分别采用室温解冻、冷藏解冻、流水解冻以及盐水解冻4种方式进行解冻,通过测定解冻后肉饼的保水性(解冻损失率、离心损失率)、pH值、TBARS值、TVB-N值,并测定猪肉饼肌原纤维蛋白羰基含量、巯基含量、蛋白溶解等,分析不同解冻方式对其蛋白氧化程度的影响。结果表明,解冻对调理猪肉饼保水性有较大影响,其中空气解冻与冷藏解冻组的保水性最好,解冻损失维持在5.03%~5.75%之间,离心损失率在31.02%~32.19%之间;同时与新鲜肉饼组相比,空气解冻、盐水解冻和流水解冻组猪肉饼TVB-N值显著上升(P<0.05),盐水解冻组TVB-N值上升至3.17 mg·100g^-1;但解冻对调理肉饼pH值、TBARS值、色泽的影响均不显著(P>0.05);通过对肌原纤维蛋白氧化程度的测定发现,解冻会引起肌原纤维蛋白羰基含量上升、巯基含量和溶解度下降,SDS-PAGE试验也证明解冻会引起蛋白质发生不同程度的降解。本研究为实际生产中冻结肉制品解冻工艺的选择与优化提供了一定的理论依据。

Effects of Thawing Methods on Quality of Prepared Pork Patties

The effects of different thawing methods on the quality of pork patties and the degree of protein oxidation was explored. The conditioned pork patties were frozen at -18 ℃, and then the frozen meat patties were thawed by four different thawing methods namely air thawing, refrigeration thawing, running water soaking and salt water soaking, respectively. The effects of different thawing methods on meat patties quality and myofibrillar protein oxidation were analyzed by the water retention properties (thawing loss rate, centrifugal loss rate), pH, TBARS value, TVB-N value, carbonyl content, sulfhydryl content, protein solubility, and SDS-PAGE gel electrophoresis. The results showed that thawing methods had a great effect on the water retention of the prepared pork patties. Air thawing and refrigeration thawing showed the best water retention, the thawing loss was 5.03%-5.75%, and the centrifugal loss was 31.02%-32.19%. At the same time, thawing of air, salt water and running water caused significant increase of the value of TVB-N (P<0.05), especially the value of TVB-N was increased to 3.17 mg·100 g^-1 by salt water thawing, but the effect of thawing on pH value, TBARS value and color difference of the prepared meat patties were not significant (P>0.05). Through the determination of the oxidation degree of myofibrillar protein, it was found that thawing methods could increase the carbonyl content of myofibrillar protein, decrease the sulfhydryl content and solubility, confirmed by SDS-PAGE electrophoresis. Comparing the thawing methods used, the oxidized degree of myofibrillar protein in refrigeration thawing was thelowest, so the quality of prepared pork patties could be well maintained. This study provides a theoretical basis for the selection and optimization of the freezing thawing process of frozen meat products for the actual production.