Study On The Process Optimization And Quality Change Of Pomegranate-apple Compound Juice Beverage During Storage Based On Ultra-high Pressure Technology

Ultra-high pressure technology is a nonthermal technology,better retention of fruit and vegetable nutrients,aroma components and flavor,has been widely used in the processing of fruit and vegetable juice beverage.South xin jiang is rich in pomegranate,apple resources,variety,high nutritional value,widely distributed.Acid pomegranate has high medical value,but it is difficult to eat fresh due to it is to acor.At present,these two fruits are mainly sold fresh,but the shelf life is short,a large amount of waste of resources.In order to further improve the use of acid pomegranates,apples value;To provide people with a new compound juice beverage;In this study,used acid pomegranates and apples,using ultra-high pressure technology,through single factor test,orthogonal optimization test and other methods,the technological formula of pomegranate-apple compound juice beverage was determined,the process parameters of ultra-high pressure sterilization and the type and ratio of stabilizer were optimized,the change of quality during storage was research,and the shelf life of products is predicted by shelf life prediction test.the research contents and results are as follows:(1)Determination of raw material formulation:Enzymatic hydrolysis of pomegranate juice and apple juice,the compound juice beverage technology was optimized by single factor test and orthogonal test.The best process is:added amount of granulated sugar is 3 %,the ratio of acid pomegranate juice to apple juice to water is 6:10:3(V/V),pH value of 3.5.the color of pomegranate-apple compound fruit juice beverage is reddish,fragrant,taste coordination,sweet and slightly sour.(2)Study on stability test:Choose the konjac gum,agar,arabic rubber powder,sodium carboxymethyl cellulose(CMC-Na),and so on Seven stabilizers including gelatin.It can be seen from the results of single factor test,the effect of single stabilizer on the stability of pomegranate-apple compound juice beverage was not good.Further compounding ratio,It was found that the ratio of konjac gum to agar was 3:2(V/V)and the concentration was 0.16 %,the stability of pomegranate-applecompound juice beverage was better.The centrifugal sedimentation rate was1.43 %;was lower 55.31 % than that use of 0.16% konjac gum alo(3)Optimization of ultra-high pressure sterilization process:The effects of different parameters on bactericidal efficacy and quality were studied.the results showed that:With the increase of pressure and the prolongation of holding time,the death rate of microorganism in pomegranate-apple compound juice beverage also increased,the optimal sterilization process parameters are:500 MPa processing 20 min,synergistic temperature is 25 ℃,under the condition of this technology,the pomegranate-apple compound juice beverage has achieved good bactericidal effect,pH,total acid,soluble solids,color,flavor and taste tend to best able.(4)Shelf life prediction:The accelerated shelf life test was carried out with the indexes of total acid,soluble solids,pH,centrifugal sedimentation rate and sensory evaluation.It is predicted that the shelf life of pomegranate-apple compound juice is shelf life at 4 ℃ was 207 d,and the shelf life at 20 ℃ was 58 d.After ultra-high pressure storage period,pH,centrifugal sedimentation rate,total acid,Soluble solids basically unchanged,was not detected bacteria during the whole storage period,better maintain the sensory quality of pomegranate-apple compound juice beverage.