不同方式二次杀菌的红烧卤牛肉在贮藏期间的品质变化

Quality Changes of Braised Beef during Storage after Two Cycles of Sterilization with Different Methods

摘要:

为延长红烧卤牛肉保质期，但不影响产品感官品质。将红烧卤牛肉真空包装后，采用三种杀菌方式：沸水杀菌1（BWS1），沸水杀菌30 min；BWS2为沸水杀菌30 min，室温放置48 h再沸水杀菌30 min；高温杀菌（HTS），杀菌公式为15′-28′-15′/121 ℃；未杀菌组（CK）。CK、BWS1和BWS2组在0~4 ℃、HTS组在常温下贮藏。4组产品在0 d进行感官评定，并测定其在贮藏过程中的微生物及理化指标变化。结果表明，CK组在贮藏第14d时微生物数超标（菌落总数、乳酸菌数、假单胞菌数、肠杆菌科数分别为4.38 lg(CFU/g)、4.28 lg(CFU/g)、4.01 lg(CFU/g)、<1 lg(CFU/g)），TBARS值升高至0.18 mg/kg，pH、色差值和亚硝残留量显著降低。HTS组贮藏过程中未检出微生物，BWS1和BWS2组在贮藏第180 d时，微生物数尚未超标，尤其BWS2组显著低于BWS1组（p<0.05）。随着贮藏时间的延长，BWS2组亮度值最高，亚硝残留量显著低于BWS1组（p<0.05），脂肪氧化程度最低（TBARS值为0.42 mg/kg），感官品质良好。故此，对红烧卤牛肉进行2次沸水杀菌是较好的杀菌方式，可以较好地保持产品品质，又能使冷藏期延长至180 d。

Abstract:

In order to extend the shelf life of stewed beef without affecting its sensory quality, the braised beef after vacuum packaging was sterilized in three ways: boiling water sterilization 1 (BWS1; boiling water sterilization for 30 min); boiling water sterilization 2 (BWS2; boiling water sterilization for 30min, then standing at room temperature for 48h, and finally boiling water sterilization for 30 min); High temperature sterilization (HTS); sterilization formula was 15'-28'-15'/121 ℃). A non sterilized group was set up as the CK group. The CK, BWS1 and BWS2 groups were stored at 0 ~ 4 ℃, whilst the HTS group was stored at room temperature. Sensory evaluation was performed on the four groups of products on Day 0, and the changes in microbial and physico-chemical indexes during storage were measured. The results showed that the number of microorganisms in the CK group exceeded the standard on the 14th day of storage (total colony count, Lactobacillus count, Pseudomonas count, Enterobacteriaceae count were 4.38 lg (CFU/g), 4.28 lg(CFU/g), 4.01 lg(CFU/g) and < 1 lg (CFU/g), respectively), the TBARS value increased to 0.18 mg/kg, and the pH, color difference and nitrite residue decreased significantly. No microorganisms were detected in HTS group during the entire storage. The number of microorganisms in BWS1 and BWS2 groups did not exceed the standard limit on the 180th day of storage, especially the number of microorganisms in BWS2 group was significantly lower than that in BWS1 group (p<0.05). With the extension of storage time, the BWS2 group had the highest luminance value, significantly lower content of nitrite residue than BWS1 group (p<0.05), the lowest degree of lipid oxidation (TBARS 0.42 mg/kg), and good sensory quality. Therefore, two cycles of boiling water sterilization of stewed beef is a better sterilization method, which can maintain better the product quality while prolonging the cold storage period to 180 days.