Process Research On Fruit And Vegetable Juice-Yogurt Beverage Based On Double Fermentation

The paper studied a kind of special flavor and rich in nutrition fermented milk beverage which is fermented by compound lactobacillus based on fruit and vegetable juice,milk respectively,then compounded with the additives such as sweeteners,sour agents,stabilizers and others.Firstly,the paper studied the best ratio of compound lactobacillus,tamed strain,selection and optimization on the condition of the fermentation for the fruit and vegetable juice.Secondly,determination on the ration of compound fruit and vegetable juice,evaluation on the double fermentation beverage formula and the stability,finally,evaluation on the quality of beverage via systematic sensory evaluation and selection of the best formula and process parameters.The paper also compared the change of amino acid and fragrance substance of fruit and vegetable juice before and after fermentation,and the result could provide target level of product quality in the process of industrial production.Comparing to single cultures and compound lactobacillus fermentation respectively,the result showed compound lactobacillus fermentation had a better effect,and CH-1 had the optimum effect to ferment carrot juice after separate domestication.Taking the single factor experiment and orthogonal experiment on the conditions of fermentation,determination of the inoculum size,temperature,and the dilutability of the carrot juice for fermentation.Determination of the ratio of fermented fruit and vegetable juice as semi-finished product by single factor experiment,the specific ratio was 7:2:1(Brix12(fermented carrot juice): concentrated orange juice: concentrated apple juice).According to the determined ratio above,prepared the double fermentation fruit and vegetable juice which was optimized by orthogonal experiment.Taking a large number of single factor experiments and orthogonal experiments on the preparation of double fermentation fruit and vegetable juice,finally,the determined best formula of the beverage was fermented milk 40%,compounded fruit and vegetable juice 40%,white granulated sugar 9%,pH value 3.8,and the ratio of percentage of unfermented orange juice and apple juice added in the fermented carrot juice 20%:10%.And the influence size of each factor: pH value>content of fermented milk>content of white granulated sugar> content of fruit and vegetable juice> unfermented orange juice and apple juice added in the fermented carrot juice.Due to dietary fibers of juice,protein denaturation of yogurt,low viscosity to increase the chance of the precipitation and drainage,the study took the single factor experiment and orthogonal experiment on the stability of kinds of common stabilizing agents which could stabilize double fermentation fruit and vegetable juice-yogurt beverage,the result showed optimum dosage of stabilizers were CMC 0.5%,pectin 0.3%,and PGA 0.4%.The paper analyzed the fragrance and amino acid substances before and after the fermentation of carrot juice,found six new fragrance substances in the fermented carrot juice,and the content of the existing five fragrance substances in unfermented carrot juice increased inordinately;and the content of 12 kinds in the existing 17 kinds of amino acid obviously increased,the other two kinds had no change,and generated a new kind of amino acid.WTAA increased from 7.544% to10.943%.The study attained a kind of fruit and vegetable juice-yogurt beverage based on double fermentation which could be in industrial production.In this paper,we created the complete formula and all process parameters for industrial production,and set up sensory,physical and chemical and health criterion which could be very helpful for industrial guidance.