Impact of Low-temperature Storage on Volatile Flavor Compounds in Prepared Pork Products

[Objectives]This study was conducted to explore the dynamic changes of volatile flavor compounds in prepared pork during storage at different low-temperature conditions.[Methods]Prepared pork was stored at 4,-4 and-18℃.The volatile flavor compounds of prepared pork were determined by solid-phase microextraction-gas chromatography-mass spectrometry(SPME-GC-MS)at days 0,7,14,21 and 28,and relative odor activity value(OAV),principal component analysis(PCA)and cluster analysis(CA)were combined to analyze changes in volatile flavor compounds of prepared pork during storage.[Results]The total number of volatile flavor compounds gradually decreased with the prolongation of the storage period,and OAV analysis identified 22 key flavor compounds(OAV≥1).The results of PCA and CA showed that 2-methyl-1-butanol,1-octen-3-ol,linalool,cineole,hexanal and nonanal were the main key flavor components,and the degree of flavor degradation was low under both superchilling and freezing conditions.After 28 days of storage,the alcohol content in the chilling group was significantly higher than other two groups,and the overall content of volatile flavor compounds was also significantly higher than other two groups,indicating that the-4℃chilling storage was more favorable for maintaining the overall flavor of prepared pork.[Conclusions]This study provides a theoretical basis for finding a better storage method for prepared meat products.

牛肉饼加工工艺优化及辣椒油树脂抗牛肉蛋白氧化效果研究

辣椒油树脂(capsicum oleoresin,CO)是从辣椒中提取、浓缩制得的一种天然食品添加剂,具有良好的抑菌、抗氧化和清除自由基能力。本研究以感官评分为依据,通过正交实验优化牛肉饼热加工工艺,并测定了烤制、油炸和预调理牛肉饼在贮藏期内羰基、巯基和丙二醛等指标含量,探究辣椒油树脂抗牛肉蛋白氧化效果。结果表明:烤制牛肉饼的最佳加工工艺为190℃、12 min,CO添加量为0.2 g/kg,油炸牛肉饼的最佳加工工艺为150℃、1.5 min,CO添加量为0.2 g/kg;在3种不同的加工条件下,当贮藏至第9 d时,与对照组相比,CO对蛋白质羰基的抑制率分别为39.3%、25.4%、12.0%,对蛋白质巯基的保护率分别为4.4%、3.0%、40.5%,对丙二醛的抑制率分别为6.9%、18.7%和36.1%。研究发现,辣椒油树脂具有一定的抗氧化效果,可为辣椒油树脂及辣椒在肉制品加工中的应用提供一定的参考。

玫瑰雪菊混合浓缩液在预调理牛肉片中的保鲜研究

以玫瑰和雪菊为原材料,采用超声波水提法制备天然玫瑰雪菊混合浓缩液,分别与山梨酸钾(1.0g/kg)和Vc(0.1mg/mL)进行抗氧化与防腐效果比较,并将混合浓缩液应用于预调理牛肉片的贮藏保鲜实验。结果表明:玫瑰雪菊混合浓缩液的DPPH·自由基清除率和羟基自由基清除率分别可以达到82.50±0.06%和80.26±0.03%,优于Vc推荐浓度。抑菌方面,玫瑰雪菊混合浓缩液的吸光度可以达到0.564±0.02,与山梨酸钾效果相近。经过混合浓缩液浸泡处理的预调理牛肉片的pH、TVB-N、TBARs、羰基含量和菌落总数都优于对照组。

响应面法优化速冻预调理牛肉片中复合无磷持水剂的配比

通过响应面法优化了速冻预调理牛肉片中无磷持水剂的配比,结果显示最优配比为乳酸钠添加量0.30%、柠檬酸钠添加量0.50%、碳酸氢钠添加量0.80%,在此配比下牛肉片的吸水率可达48.0%。将加入复合无磷持水剂处理的试验组与未经复合无磷持水剂处理的对照组相比,通过相关指标测定结果显示试验组感官评分、吸水率更高,解冻损失率及蒸煮损失率更低,L值和a值更大。研究结果表明使用复合无磷持水剂可有效抑制速冻预调理牛肉片水分流失和蛋白质氧化变性,有助于提高速冻预调理牛肉片吸水率,保持速冻预调理牛肉片良好品质,为速冻预调理肉制品的生产加工提供理论依据。