Fabrication Of Bacteriostatic Absorbent Mats Based On Electrospinning Technology And Its Effect On The Preservation Of Chilled Meat

Chilled meat has the advantages of soft texture,good flavor,and high nutritional value,which contribute to its gradually expanding market share.However,juice loss,microbial reproduction,and fat oxidation of chilled meat occur during storage,shortening the shelf life,deteriorating the food quality,and causing serious economic losses.Nowadays,air-laid paper absorbent mats are often placed in cooling packages to absorb blood water,thus improving the hygienic environment inside the package.However,because the absorption of blood water and inhibition of the growth of spoilage bacteria are limited,the preservation of chilled meat is still not ideal.This situation demands an absorbent mat with high water absorption and antibacterial properties.In this experiment,a nanofiber,antibacterial,absorbent mat rich in eugenol was prepared by electrospinning technology combined with citric acid as a green crosslinking method,and the structure and antibacterial activity were systematically characterized.To test its application,the effect of the antibacterial,nanofiber,absorbent mat on the storage quality of chilled meat in modified atmosphere packaging was also evaluated,which provides a theoretical reference for extending the shelf life of chilled meat.The specific research results were as follows:(1)As the level of polyvinyl alcohol was increased(5%,7.5%,10%,12.5%),the surface tension,conductivity,and viscosity of the spinning solution increased significantly(P<0.05),whereas the p H value was not affected(P>0.05).Moreover,when the polyvinyl alcohol content of the spinning solution was 7.5%,electrospun nanofibers with good morphology and uniform diameter could be prepared,but higher proportions(10% or 12.5%)significantly reduced the spinning rate.Therefore,the spinning solution with 7.5% polyvinyl alcohol was selected to prepare the nanofiber absorbent mat.(2)Increasing the citric acid level(3%,6%,9%,12%)increased the conductivity of the spinning solution(P<0.05)and decreased the p H value and nanofiber diameter(P<0.05).The degree of crosslinking between citric acid and polyvinyl alcohol was also increased.After crosslinking,the thermal stability,mechanical properties,surface hydrophobicity,and water stability of the nanofiber absorbent mat increased(P<0.05).However,at 12% citric acid,the swelling rate of the absorbent mat was reduced(P<0.05).Therefore,optimal crosslinking was achieved with 9% citric acid.(3)Increasing the amount of eugenol(5%,10%,15%,20%)decreased the swelling capacity,water stability,water vapor transmission rate,and elongation at break of the antibacterial,nanofiber,absorbent mat(P<0.05),but tensile strength increased first and then decreased.The tensile strength was maximized at 15% eugenol.The addition of 10% eugenol resulted in nanofibers with uniform morphology,but doubling the amount(20%)destroyed the stable spindle structure of the nanofibers.In addition,antibacterial experiments showed that the nanofiber,absorbent mat containing eugenol had a significant inhibitory effect on Escherichia coli and Staphylococcus aureus,and this effect increased as the amount of added eugenol was increased.(4)Examining the effect of the antibacterial,nanofiber,absorbent mat on the storage quality of chilled meat in modified atmosphere packaging revealed that as the eugenol content was increased(5%,10%,15%,20%),the fresh-keeping effect first increased and then decreased.The antibacterial,nanofiber,absorbent mat with 15% eugenol exhibited the best preservation effect on chilled meat.Compared with the blank group and the air-laid paper group,the antibacterial absorbent mat with eugenol reduced the total colony count,total volatile base nitrogen,thiobarbituric acid value,and the p H value of chilled meat during storage(P<0.05).In addition,the water retention and color deterioration of the chilled meat improved in the antibacterial absorbent mat group relative to the blank and the air-laid paper(P<0.05).When the eugenol content was 15%,the relative abundance of spoilage bacteria on day 15 of chilled meat was significantly lower compared to the blank group and the air-laid paper group(P<0.05).In summary,the nanofiber absorbent mat containing 15% eugenol has the best preservation effect on chilled meat and can extend the shelf life of chilled meat by 5-6 days compared to the blank group.