Development And Quality Analysis Of Walnut Meal And Red Date Composite Solid Beverage

Walnut meal is a kind of good food raw material,which is the residual by-product of cold-pressed walnut kernel oil and contains rich nutrients such as protein and dietary fiber.The walnut meal obtained by cold pressing method can maintain rich nutrition and good quality.Jujube is rich in reducing sugar,vitamin C,amino acids,trace elements and other nutrients.In this paper,cold pressed walnut meal and jujube were used as main raw materials to produce walnut meal and jujube composite solid beverage,and the processing techniques,product formulation and shelf life of walnut meal and jujube composite solid beverages were studied.The main research results are as follows:1.The two methods of vacuum freeze-drying and spray drying were investigated and compared.spray drying is better than vacuum freeze-drying in terms of time consumption,water content,bulk density,color difference,solubility,microstructure,protein digestion in vitro,amino acid content and volatile substances.The best drying method is spray drying.2.The spray drying process was optimized,and the four factors of inlet air temperature,feed flow rate,air intake volume and soluble solid content were selected for single factor test.Combined with response surface analysis,the optimal process parameters of spray drying of walnut meal and jujube composite solid beverage were obtained.The inlet air temperature 1s 183?,the feed flow rate is 0.3 L/h,the air inlet volume is 50 m3/h,and the soluble solid content is 7 Brix.Under these conditions,the walnut powder red jujube composite solid beverage powder collection rate of 59.50%,the angle of repose of 400,the bulk density of 0.23 g/mL,and the moisture content was 1.5%.3.In order to improve the solubility of the walnut meal and jujube composite solid beverage and reduce the sticking phenomenon during the spray drying process,an appropriate amount of food additive should be added during the processing,and the type selection and dosage of the food additive should be adopted through single factor test and orthogonal test.The sucrose fatty acid ester was selected as emulsifier,p-cyclodextrin as stabilizer and maltodextrin as a dry aid,the amount of addition is 3.5%of the quality of walnut meal,1.4%and 5%,respectively.After verification experiments,the walnut meal and jujube composite solid beverage had the best stability after adding food additives,the spray drying effect is good,the sticking phenomenon is lighter,and the brewing solution is changed from Newtonian fluid to non-Newtonian fluid,the viscosity is slightly increased,and the product stability Significantly increased.The sensory optimization experiment was carried out on the walnut meal and jujube composite solid beverage,and the best formula was walnut meal and jujube composite powder 45 g,vegetable fat powder 55 g,white sugar 31 g,caramel color 3 g.The solid beverage prepared according to this formula had a combined sensory score of 88.32.4.During the storage process,the walnut meal and jujube composite solid beverages are affected by factors such as storage time and storage temperature.The low temperature condition helps the product to store,and has certain control on the moisture content,peroxide value and stability coefficient of the product,and can maintain good color,flavor and tissue morphology.At room temperature(25°C)under storage,has no great influence on the quality of the product.Storage temperature below 25°C,the storage period of up to 70 d.