负载十三香精油的明胶/桃胶可食性膜构建及其在猪肉保鲜中的应用OA

Edible antibacterial composite films loaded with thirteen-spices essential oil(TSEO)were prepared using gelatin(G)and peach gum(P)as film-forming material at three mixing ratios(composite films with mass ratios of G to P of 3:1,1:1,and 1:3 were named GP3:1,GP1:1,and GP1:3,respectively).The application effectiveness of the composite films was evaluated by determining their physical properties,antibacterial activity and effects on the preservation of chilled pork.The results showed that the GP1:3 composite film with 1 g/100 mL TSEO added had the best performance.Its thickness was(0.09±0.01)mm,which is within the thickness range commonly used for food packaging films.The film had the following color parameters:brightness value(L*)86.58±0.07,redness value(a*)-0.05±0.14,yellowness value(b*)24.22±0.70,total color difference 21.85±0.72,and whiteness index(WI)74.53±0.66;the color could be regulated by adjusting the G/P ratio and the amount of added TSEO.In terms of optical performance,the composite film had both ultraviolet resistance and light transmittance within the wavelength range of 200-800 nm.The swelling degree was as high as(58.95±0.47)%.Due to its high water absorption and swelling capacity,the film effectively retained the moisture exuded during food storage.The GP1:3+TSEO film contained only(0.073±0.007)%volatile components,effectively limiting their escape.The retention rate of TSEO during the film-making process was(6.13±0.23)%,indicating that the composite film could immobilize TSEO.In contact with fatty food simulants,the release rate of TSEO incorporated in the GP1:3 composite film was the highest,reaching(9.42±0.76)%,which was conducive to creating an antibacterial environment.The diameters of the inhibitory zones against Staphylococcus aureus and Escherichia coli reached(8.11±0.50)and(8.13±0.50)mm,respectively.The total viable count(TVC)and pH of chilled pork packaged with the composite films and stored at 4℃increased significantly during storage(P<0.05).On the 8th day,the TVC values of the control and wood fiber paper treatment groups reached(6.200±0.226)and(6.170±0.069)(lg(CFU/g))respectively,and the pH values reached 6.71±0.18 and 6.73±0.07 respectively,indicating the pork samples to be spoiled.However,the TVC and the pH value of the GP1:3 composite film treatment group did not reach the spoilage threshold until the 10th day.This composite film extended the shelf life of pork by 2-3 days,and effectively delayed meat spoilage.Moreover,the a* of chilled pork treated with this film was higher than those of the control and wood fiber paper treatment groups,and the increase in b* was small,suggesting that the composite film effectively suppressed the decrease in redness and yellowing phenomena.