Variation Rule Of Quality In Storage Of Prepared Beef Patties

With the quickening pace of life,prepared meat products are widely loved by people because of their convenience and popular taste.During the processing and storage of prepared meat products,oxidative rancidity is the main cause of product quality deterioration,which brings economic losses to producers,sellers and consumers.More importantly,oxidative rancidity is likely to produce toxic and harmful substances,which will bring harm to human body after ingestion by mistake,such as carcinogenesis and mutation.Thermal processing method has a crucial influence on the quality of meat products.High temperature and long time heating will accelerate the oxidation of meat products.Adding antioxidants is one of the effective ways to control or delay the oxidative rancidity of meat products.Natural antioxidants have attracted much attention because of their safety and non-toxicity.Among them,some plant extracts have been proved to have safe and reliable antioxidant effect and are gradually applied in the food industry production.In this paper,by studying the change rule of prepared beef patty storage quality and establishing a prediction model of shelf life in storage period,we hope to provide some reference for the processing storage and thermal processing methods of prepared meat products and the screening of plant extracts with antioxidant properties.The main research results are as follows:(1)Study on the change rule of macro storage quality of prepared beef pattiesIn this paper,the longissimus dorsi muscle as the main experimental material,combined with soybean protein powder and other seasonings to develop a certain nutritional value of the prepared beef patty:longissimus dorsi muscle 95.0%(w/w),soybean protein powder 1.2%(w/w),oil consumption 1.0%(w/w),flaxseed oil 2.0%(w/w),salt 0.8%(w/w).The prepared beef patty without plant extract antioxidant was used as the control group,and the prepared beef patty with 0.02%grape seed extract,0.02%rosemary extract and 0.01%L.Barbarum polysaccharide were used as the treatment group,respectively.The thiobarbituric acid reactive substances value in beef cake were determined by means of oven baking and microwave heating.After cooling,they were packed in vacuum and stored in a 4? constant temperature refrigerator for 0,10 and 20 days.Thiobarbituric acid reactive substances value,carbonyl content,texture profile analysis,shear force,color(L*,a*,b*,c*,h)and sensory evaluation.The results showed that two kinds of thermal processing methods and three kinds of plant extracts had significant effects on the storage quality of prepared beef patties(p<0.05).Microwave heating is more beneficial to inhibit lipid and protein oxidation of prepared beef patties,among which,0.02%grape seed extract has relatively good antioxidant effect,thiobarbituric acid reactive substances value is 0.6 mg MDA/kg,carbonyl content is 1.2 nmol/mg.The texture profile analysis index values of the beef patties prepared by microwave heating were higher.The shear force value of the prepared beef patties in the oven is smaller than that in the microwave heating,the minimum value is 2101.333 g,and the a*value of the surface and section is higher,while the h value is lower.The 0.02%rosemary extract and 0.01%lycium barbarum polysaccharide could significantly reduce the cooking loss of vitamin B2,and the highest content reached 0.084 mg/100 g after cooking.The total content of pyridoxal and pyridoxol in oven baked beef patties was higher than that in microwave heated groups,and the highest content reached 0.138 mg/100 g after cooking.The sensory score of baked beef patties was higher than that of microwave heating,and the sensory properties of processed beef patties were significantly better when 0.02%rosemary extract was added,showing better color and cheesy smell.In conclusion,oven baking is more conducive to maintaining the macroscopic storage quality characteristics of beef patties.(2)Study on the change rule of micro-storage quality of prepared beef pattiesThe surface hydrophobicity and sulfhydryl content of myo fibrillary protein,in vitro gastrointestinal digestibility and microstructure of muscle fiber were determined during the storage of prepared beef patties.The results showed that the surface hydrophobicity of myofibrillar protein in beef patties was more stable after baking in the oven without adding plant extract antioxidant.The binding amount of bromophenol blue added with 0.01%L.Barbarum polysaccharide and microwave heating was 51.808 ?g,which was more conducive to maintaining the stability of the surface hydrophobicity of myofibrin in beef patties.The addition of 0.02%grape seed extract combined with oven baked beef patties increased the reactive sulfhydryl content by 5.795 mmol/g,and decreased the total sulfhydryl content by 5.711 mmol/g,which was more conducive to maintaining the stable su]fthydryl content of beef patties myofibrilic protein.The in vitro gastrointestinal digestibility of baked beef patties was higher than that of microwave heating,reaching 93.46%,and the intestinal digestibility of all beef patties was higher than that of stomach.The two kinds of thermal processing methods and plant extracts had great influence on muscle fiber structure,adding 0.01%L.Barbarum polysaccharide was more beneficial to maintain the integrity of muscle structure.In conclusion,oven baking combined with 0.01%L.Barbarum polysaccharide is more conducive to maintaining micro-storage quality characteristics of beef patties.(3)Construction of a prediction model for the shelf life of prepared beef patties during storageUsing thiobarbituric acid reactive substances value and carbonyl content as the main evaluation indexes,linear fitting and polynomial fitting were performed respectively.The results showed that the determination coefficient R2 of the polynomial fitting equation for thiobarbituric acid reactive substances value and carbonyl content of beef patties during storage period was 1.00000,indicating high fitting degree and good model effect.The linear fitting equation determination coefficient(R2)of the thiobarbituric acid reactive substances value of the oven baked beef Patty were 0.99053,0.99938,0.99628 and 0.99893,respectively.The linear fitting equation determination coefficient(R2)of the microwave heated beef patty thiobarbituric acid reactive substances value were:0.96409,0.99152,0.99628,0.99254.Except that the R2 of microwave heating control group was less than 0.99,the R2 of other groups was greater than 0.99,indicating that the model effect was good.The linear fitting equation determination coefficient(R2)of carbonyl content in oven baked beef patties were 0.75642,0.92372,0.84478,0.42689,respectively.The linear fitting equation determination coefficient(R2)of carbonyl content in microwave heated beef patties were:1.00000,0.99168,0.94527,0.59919,the effect of linear fitting prediction model of carbonyl content was poor.Therefore,the prediction model of thiobarbituric acid reactive substances value of prepared beef patties has high accuracy,which can provide some theoretical reference for monitoring the quality change of meat products during storage.