Walnut planting is widely distributed in China,walnut kernels because of their high nutritional value and health food function is loved by consumers,and other components of walnuts such as walnut shells,distracted wood,etc.as waste in the industrial processing process,resulting in waste of resources and environmental pollution,and studies have shown that these by-products contain functional ingredients such as antioxidants and bacteriostasis.Chinese sausages are loved by consumers in China,but their high fat characteristics lead to the product is very easy to oxidize and deteriorate,in the process of industrial processing and production,often use synthetic antioxidants and chemical preservatives to inhibit bacterial preservative and inhibit rancidity,although these food additives in accordance with the national food additive health standards when added safe,but possible abuse and improper use also have certain safety risks.Moreover,with the change of consumption concepts,people are more looking forward to the ingredients added in meat products from natural products,and the search for natural plant extracts that can replace the function of synthetic antioxidant and bacteriostatic additives has received special attention.In this project,the content analysis of total phenols and total flavonoids was analyzed and in vitro antioxidant and antibacterial activity experiments were carried out after extraction from walnut shells,walnut kernels and distraction.The results showed that the total phenolic and total flavonoids of the distraction extract were the highest,and the antioxidant properties and antibacterial activities in vitro were the best.Further 0.05%,0.15% and 0.30% distraction wood extracts were added to Chinese sausages,compared with 0.02% antioxidant food additives BHA and BHT(BHA:BHT =1:1),and a blank group was set up to compare the antiseptic preservation and quality characteristics of the neutral sausages during the storage period of0~35 days,and the main results were as follows:(1)The analysis of component content,in vitro antioxidant and in vitro bacteriostatic properties of walnut parts showed that the total phenolic content of walnut shell,walnut kernel and distraction extract was 5.34±0.29 mg GAE/g,8.12±0.29 mg GAE/g,10.44±0.39 mg GAE/g,respectively;The total flavonoid contents were 7.78±0.25 mg QE/g,12.91±0.81 mg QE/g,and23.88±0.39 mg QE/g,respectively.The half inhibitory IC50 s of DPPH radical scavenging rate were 0.25 mg/mL,0.13 mg/mL and 0.05 mg/mL,respectively,and the half inhibitory IC50 of ABTS+ radical scavenging rate were 0.95 mg/mL,0.46 mg/mL and 0.08 mg/mL,respectively,and the total antioxidant capacity was 1.47 mmol/g,2.54 mmol/g,and 4.01 mmol/g,respectively.The MICs for Staphylococcus aureus were 50 mg/mL,50 mg/mL and 12.5 mg/mL,and for Escherichia coli: 25 mg/mL,12.5 mg/mL and 6.25 mg/mL,respectively.MBCs for Staphylococcus aureus were 100 mg/mL,100 mg/mL,and 25 mg/mL,respectively,and MBCs for Escherichia coli were 50 mg/mL,25 mg/mL,and 12.25 mg/mL,respectively.The total phenolic and total flavonoid content,in vitro antioxidant properties and in vitro antibacterial activity of walnut extracts were as follows: distraction wood extract> walnut kernel extract >walnut shell extract.(2)The physicochemical characteristics of Chinese sausages added with 0.05%,0.15%,0.30% distraction extract,0.02% food additive BHA and BHT(BHA:BHT=1:1)control group and blank group were studied,and the experimental results: the pH,moisture content and water activity of Chinese sausages added with distraction extract were not significantly different,but they could significantly inhibit their acid value,peroxide value,malondialdehyde,volatile saltbased nitrogen value,protein oxidation,and add 0.15%,The acid price of Chinese sausages in the 0.30% concentration of distraction wood extract group was lower and the performance effect was better than that of the control group.The peroxide value of the group with 0.30%concentration of distraction extract was the smallest overall,indicating that the control group and Chinese sausages with different concentrations of extract could inhibit the primary oxidation of oil,and the primary oxidation effect of distraction extract on lipids was concentration-dependent.The TBARS values of each group were significantly lower than those in the blank group,and the TBARS values of the three groups with the added extract were lower than those in the control group and the blank group during the whole storage time,but the TBARS value was not positively correlated with the concentration of the extract.The TVB-N values showed a significant upward trend,and when the added content of distraction wood extract sausage reached 0.15%,it had a good effect on the spoilage of sausage,and even better than the inhibition level of the control group.The content of protein carbonyl group in the blank group was the highest in each group,and the protein inhibition effect of 0.15% and 0.30%distraction extract group was stronger than that of the control group,which was concentrationdependent,while the content of protein sulfhydryl group decreased significantly with the extension of storage time,and there were significant differences between the blank group and the other four groups,among which the content of protein sulfhydryl group was concentrationdependent with the addition of distraction extract.(3)With the extension of storage time,the total number of colonies increased significantly.In the same storage period,there were significant differences between the blank group and other groups,and the total number of colonies in the blank group was the highest during the whole storage period,and on the 35 th day,the total number of colonies in the group with 0.15% and0.30% distraction extract was lower than that in the control group,and the total number of colonies in the 0.30% distraction extract group was the lowest.The results showed that distraction wood extract had the effect of inhibiting microorganisms,preserving,and improving the quality of sausages in Chinese sausages. |