Preparation Of Bionic Silkworm Cocoon Shell Packaging And The Research Of Its Effect On Cottage Cheese Quality

Dairy produce industry is an important pillar industry in agriculture and animal husbandry in Inner Mongolia.Among them,cottage cheese is a characteristic dairy product of Inner Mongolia and is deeply loved by the Mongolian people.However,during storage,the cheese tends to lose moisture and dry out and harden.Its fat is precipitated.The sales is limited because of tough storage.Changing traditional packaging and enhance consumers' purchasing desire,bionic packaging is adopted in this paper.Silk fibroin,polyvinyl alcohol and polylactic acid,which are natural materials,are blended by electrostatic spinnning technology to obtain nano-fiber bionic packaging and its effect on the quality of cottage cheese is studied.The main findings are as follows:Firstly,taking cocoon shell as bionic object and cottage cheese curd as research object,Silk fibroin,polyvinyl alcohol and polylactic acid,which are environmentally friendly materials,are respectively mixed to prepare spinning solution,and the fiber membrane is successfully bionic on the surface of cottage cheese by adopting electrospinning technology.The diameter of silk fibroin and polyvinyl alcohol blended fibers was 320nm,and the diameter of silk fibroin and polylactic acid blended nanofibers was 550nm by scanning electron microscopy.The fiber has good morphology and uniform distribution.Moreover,The successful bionic packaging observed on the surface of cottage cheese by scanning electron microscope.Tensile test results show that the mixed fiber with silk fibroin is more flexible,and the compactness of the fiber is further improved and conforms to the texture characteristics of cottage cheese.The moisture permeability showed that the moisture permeability decreased after silk fibroin was added,and the moisture permeability of double-layer bionic packaging was lower,which played a further role in moisture resistance.Secondly,the total number of colonies showed that the total number of colonies in bionic packaging with PVA/SF as inner layer and PLA/SF as outer layer was at least 5.9log(CFU/g),which could effectively resist the invasion of enthetic microorganisms and had better protection effect on cottage cheese.Finally,physical and chemical indexes showed that bionic packaging with PVA/SF as inner layer and PLA/SF as outer layer had obvious influence on the texture of cottage cheese,and improved the hardness and chewiness of cottage cheese.The bi-layer bionic packaging effectively controls the fat precipitation of cottage cheese,and bionic packaging containing PLA/SF nanofibers had no significant effect on the pH and free amino acid content of cottage cheese.