Study On The Product Of Fresh Jujube Composite Pulp

Jujube is one of the fruits with homology of medicine and food,and it is one of the special functional foods in China.Fresh jujube is especially rich in nutrition,the demand for natural and healthy food is gradually increasing,the products with jujube as the main raw material conform to this trend,and it can meet the needs of consumers in a large degree.The dried jujube juice is the main raw material for the jujube composite pulp product on market,its nutrient retention is less than that of fresh jujube juice products.The development of composite pulp product with fresh jujube composite juice as the main raw material can improve the comprehensive benefit of the fresh jujube industry,and speed up the processing and utilization of jujube.Therefore,study takes the jujube products consumer preference survey to female college students as the foundation,with fresh Chinese jujube concentrated juice as the main raw material,adding ginger juice,brown sugar and konjac gum,e response surface analysis with comprehensive sensory evaluation were used.The study gets a formulation of fresh jujube ginger brown sugar composite pulp,observed quality change of storage at room temperature in the process,and the quality of fresh jujube ginger brown sugar composite pulp,dried jujube ginger brown sugar composite pulp and Commercial product were compared.The results are as following:(1)The survey on jujube products consumer preference of female college students shows that: in the 302 valid questionnaires,the cognition of female college students on the nutritional function of jujube is higher,the highest awareness level is benefiting qi and nourishing blood reached 90.07%,followed by the beauty and anti-aging effect reached77.81%,The primary processing products of jujube(dried dates,fresh dates)are higher than the deep processing products of jujube(jujube cake,jujube drinks,etc.)in Purchase frequency.More than half of the female college students like moderate sweet and sour and sweet highlights jujube beverage.And the most choose to form a drink with jujube is brown sugar,followed by the Chinese wolf berry and dried longan.About half of the respondents chose liquid as the state and cans as the packaging for jujube drinks.Overall,female college students like jujube drinks with nutritional effect,in line with the traditional diet and moderate price.(2)The response surface analysis with comprehensive sensory evaluation were used,with fresh jujube,ginger and brown sugar as the main raw material for the study.The optimum formula of fresh jujube ginger composite pulp was as follows: the ratio of concentrated jujube juice and ginger juice were 2.6:1,the mount of addition of brown sugar were 29 g per 150 g mixed juice,and amount of addition of konjac gum were 0.4 g.This beverage was red-brown,free of impurities,sweet and sour,with the coordination of the smell of jujube and ginger,rich nutrient and unique taste.(3)The antioxidant activity of fresh jujube ginger brown sugar composite pulp were stronger,which content of total phenolics and total proanthocyanidin were 17.95 mg/g and118.66 mg/100 g respectively,and the ability to remove DPPH,ABTS and reducing power were 14.90 Trolox/100 g FW,9.76 Trolox/100 g FW and 11.59 mg/g respectively.(4)Fresh jujube composite pulp in storage process at room temperature,which content of soluble solid,total sugar,vitamin C and transmittance showed a downward trend,titration acid increased gradually.The content of total phenolics and proanthocyanidin decreased with the time,and the total phenols decreased relatively quickly in the initial stage of storage,and then the rate of decline slowed down.The change of product quality during storage is the key factor to affect the shelf life of the product.During the storage period,the overall change trend of the nutritional index was relatively flat,and the quality was stable.So fresh jujube composite pulp products can be stored at room temperature conditions,which does not affect the its edible quality.(5)In the comparison of physic-chemical properties of different Chinese jujube ginger composite pulp,the physic-chemical properties of fresh jujube ginger composite pulp are in the middle level,their contents are moderate.In antioxidant studies,there was a significant difference(P<0.05)in the comparison of content of total phenolics and total proanthocyanidin and the ability to remove DPPH,ABTS and reducing power.And the highest is fresh jujube ginger composite pulp,followed by dried ginger composite pulp,and the third is selling products.This shows that the antioxidant activity and the content of vitamin C of the fresh jujube ginger composite pulp are superior to dried jujube ginger composite pulp and commercial products,content of sugar andacid are moderate,and its quality is higher than the commercial products.