Study On The Development Of Fresh-keeping Film Of Camellia Oil-tea Meal

In this paper,the contents of polyphenols,polysaccharides and protein in the extract of Camellia oil-cake were taken as the indexes,and the effects of the ratio of material to liquid,extraction time,extraction temperature and ultrasonic assisted extraction on the extraction efficiency of Camellia oil-cake were analyzed.On this basis,the decolorization effect of different decolorizer on the extract of Camellia oil-cake was studied.According to the optimum process,the extract of Camellia oil-cake was extracted.The crude extract was mixed with the pulullan,gelatin and so on,then we got the Camellia oil-cake composite cling film.The Camellia oil-cake composite cling film was applied to the freshness of southern China of pear,and the fresh-keeping effect was evaluated.The test results are as follows:(1)Oil-tea meal pretreatment technique:The optimum extraction conditions of polysaccharide-protein mixture were as follows:no ultrasonic-assisted extraction,the ratio of material to liquid was 1:10,the extraction time was 1.5 h,and the extraction temperature was 85 ?.The decolorization effect of different decolorizer was evaluated.It was found that the optimum amount of granular activated carbon,powdered activated carbon,clay and granular activated carbon-clay mixed decolorizer was 3%,the optimum amount of activated carbon in the mixed decolorizer was 10%,the optimum decolorization temperature was 70 ?,and the optimum decolorization time was 25 min.(2)Analysis of the characteristics of Camellia oil-cake composite cling film:The single factor experiment showed that the best additions of pulullan,gelatin,Camellia oil-cake extract and lactic acid were 1.5%,5%,15%and 1.5%respectively.The results of response surface analysis show that the actual tensile strength is 113.21 ±10.39MPa and the predicted value is 107.22 MPa under the optimum conditions.The results also showed that the factors affecting the tensile strength of the composite film were mainly gelatin and Camellia oil-cake extract,and the tensile strength was sensitive to the change of the addition amount.(3)The application of Camellia oil-cake composite film in the preservation of southern China of pear:The content of organic acid,reducing sugar,soluble solids and the weight loss rate were analyzed.The results showed that the content of organic acids and reducing sugar decreased gradually with the extension of storage time.The content of organic acids in the control group decreased by 85.71%on the 90th day after storage,and the organic acids in the commercial films,PG and PGC groups decreased by 57.14%,69.66%and 60.67%respectively.The content of reducing sugar in the control group decreased by 28.57%on the 30th day after storage,and the reducing sugar in the commercial film,PG and PGC treatment groups decreased by 12.08%,20.34%and 16.01%respectively,which showed that the degree of decline is much smaller than the control group.In addition,with the prolonging of storage time,the weight loss rate of southern China of pear gradually increased,and the control group increased the rate of the largest,the commercial film increased the rate of the smallest,PGC group had a similar increasing rate to commercial film.The comprehensive evaluation of external sensory quality and internal quality of southern China of pear showed that the Camellia oil-cake composite film PGC showed good preservation effect,which is close to commercial film.