Effects Of Processing Methods On The Quality And Functional Components Of Solanum Nigrum Juice

Mature Solanum nigrum fruit has high edible value,which contains polyphenols,flavonoids,anthocyanins and other functional components,and the current Solanum nigrum related food is not available for sale,so this paper studies Solanum nigrum juice beverage.In recent years,people pay more attention to the development of food towards nutrition and health care.How to retain nutrients in food processing is of great significance.Food processing is the key technology of food,the appropriate processing method can better retain the nutrients.In this paper,Solanum nigrum was used as raw material to develop Solanum nigrum juice beverage.The changes of functional components of Solanum nigrum juice under different processing methods were studied,and the effects of processing methods on the quality and functional components of Solanum nigrum juice were investigated.The conclusions are as follows:(1)The contents of solanine and solanine in Solanum nigrum fruits at different maturity stages were significantly different.The juice prepared from Solanum nigrum at mature stage was safer to eat.The contents of solanine and solanine in immature Solanum nigrum were determined by HPLC.The results showed that the contents of solanine and solanine in immature Solanum nigrum were the highest,which were 0.276mg/g and 0.187mg/g,respectively.(2)Among the three different preparation methods of Solanum nigrum juice,steaming,extracting and squeezing,the best comprehensive quality of Solanum nigrum juice was obtained by pressing.According to the effects of different juice making methods on functional components of Solanum nigrum juice,the results showed that the functional components of juice made by pressing juice were higher than those by other methods,and the retention rate of nutritional components in Solanum nigrum juice was the highest.Among them,the total phenol content was 225.64±3.83mg/100 g,flavonoids content was 205.07±3.84mg/100 g,anthocyanin content was 58.47 ± 1.22mg/100 g,DPPH clearance rate was 75.42 ± 1.44%,ABTS clearance rate was 56.63±1.59%,color difference value was 1.21±0.06,browning degree was 4.22±0.09,soluble solid content was 10.00±0.21%,p H was 3.64±0.16,total sugar content was 4.60±0.22%,total acid content was 0.92±0.07%,Vc content was 40.72±0.18mg/100 g,transmittance was 42.78±0.29%.(3)The effects of pectinase,chitosan,centrifugation,heating flocculation,freezing and natural clarification on the clarification effect of Solanum nigrum juice were studied with light transmittance as the index.Single factor and response surface methodology were used tooptimize the clarification process.The optimal technical parameters were determined as follows: the Solanum nigrum juice was clarified at 49? for 61 min,the chitosan concentration was 0.08g/L,and the light transmittance of Solanum nigrum juice could reach 85.6%.(4)The clarified Solanum nigrum juice was mixed with Solanum nigrum juice beverage.The best formula was determined by single factor and orthogonal test with sensory evaluation as index.The results showed that(A)the addition of Solanum nigrum juice was 20%,(B)the addition of soft white sugar was 13%,(C)the addition of citric acid was 0.21%,(D)the addition of malic acid was 0.20%.(5)The effects of pasteurization,microwave sterilization and high pressure sterilization on functional components of Solanum nigrum juice beverage were compared.The results showed that pasteurization had better retention rate of components in Solanum nigrum juice.Compared with the non sterilized Solanum nigrum juice beverage,the best nutrient retention of Solanum nigrum juice beverage was pasteurized at 85 ? for 15 min.The total phenol content was 70.27 ± 3.82mg/100 g,the flavonoid content was 36.50 ± 0.98mg/100 g,the anthocyanin content was 22.13±0.75mg/100 g,the DPPH clearance rate was 66.38±1.35%,and the ABTS removal rate was 43.52 ± 1.48%.The results showed that the color and browning degree of the juice had no obvious changes.The soluble solid content was 11.80%,the total sugar content was 3.37 ± 0.11%,the total acid content was 0.51 ± 0.1%,the Vc content was 27.66±0.31mg/100 g,the p H value was 3.62±0.27,and the transmittance was84.28 ± 0.18%.Under these conditions,the finished product of Solanum nigrum juice beverage was purple red,rich in nutrients,with special aroma of Solanum nigrum,soft taste,and clear and transparent juice.In conclusion,using mature Solanum nigrum fruit as raw material,the beverage has high food safety and good market prospect.Different processing methods have certain influence on the quality and functional components of Solanum nigrum juice.Selecting the processing method with high functional components to develop Solanum nigrum juice beverage can keep flavor and rich nutritional value.It is very important to make Solanum nigrum juice products.