Study On The Physical And Chemical Characteristics Of Water Extract From Oil-spilling Lycium Barbarum And Its Application In Soybean Milk

During harvest,dry and storage,due to improper dry or air,poor storage and other problems,Lycium barbarum dry fruit will produce a large number of oil fruit,which is dark and significantly different from normal Lycium barbarum.This part of oil fruit will seriously affect the commercial value because of poor level.Therefore,how to effectively use oil-spilling Lycium barbarum to improve its utilization rate has become an urgent problem for Lycium barbarum production and processing enterprises.Because the oil fruit still contains a variety of nutrients,this paper regards the water extract of oil-spilling Lycium barbarum as the research object,compares it with different level Lycium barbarum active substance content and biological activity,preliminary explores the Maillard reaction in oil-spilling Lycium barbarum,and uses its good flavor and antioxidant activity to develop Lycium barbarum soybean milk,It provides a reference for the research and development of Maillard reaction in oil-spilled Lycium provides a theoretical basis for the research and development of Maillard reaction of Lycium barbarum.The results are as follows:(1)In this experiment,the content of 5-hydroxymethylfurfural in the water extract of oil-spilling Lycium barbarum was detected by liquid phase,which was lower than the upper limit of daily intake dose per person,proving its safety,which was the premise of its edible and utilization.The results showed that the contents of polyphenols and flavonoids in the water extract of oil-spilling Lycium barbarum were higher than those of large and small Lycium barbarum,while the content of polysaccharides was lower than large Lycium barbarum.In the antioxidant test,the water extract of oil-spilling Lycium barbarum has better antioxidant properties than big fruit and small fruit.The results showed that the original concentration of oil-spilling Lycium barbarum water extract had obvious inhibitory effect on Staphylococcus aureus and Escherichia coli.Solid phase microextraction coupled with gas chromatography-mass spectrometry(SPME-GC-MS)was used to detect and analyze the volatile components of water extracts from three kinds of Lycium barbarum.A total of 58 volatile components were detected,including esters,alkanes,aldehydes,alkenes,alcohols,ketones,heterocycles,acids,ethers,etc.Among them,only 3-hydroxy-2-butanone and 5-(1-piperidine)-2-furaldehyde were detected in the water extract of Lycium barbarum.Through Fourier transform infrared spectroscopy analysis,the molecular structure of oil-spilling Lycium barbarum and large Lycium barbarum is similar overall,The infrared spectrum scan result of small Lycium barbarum is distinguished by the C=O stretching vibration at 1720 cm-1,indicating that it contains uronic acid.(2)Based on the single factor investigation of the effect of water extract of oil-spilling Lycium barbarum,white granulated sugar and citric acid on the sensory score of Lycium barbarum soybean milk,the response surface method test was carried out to evaluate the color,tissue state,smell and taste of Lycium barbarum soybean milk,optimize the basic formula of Lycium barbarum soybean milk,and determine the optimal basic formula of Lycium barbarum soybean milk:The addition of oil-spilling Lycium barbarum water extract was 6%,sugar and citric acid was 4%and 0.05%.Secondly,with the stability coefficient as the index and the comprehensive reference viscosity,the influence of different stabilizers on Lycium barbarum soybean milk system was judged,and carrageenan,sodium alginate and guar gum were screened out to effectively stabilize Lycium barbarum soybean milk.The compound stabilizer was determined by orthogonal test as follows:guar gum 0.01%,carrageenan 0.03%,sodium alginate 0.005%.Under these conditions,the Lycium barbarum soybean milk has good stability,low viscosity and the best taste.(3)According to the national standard items and detection methods,the total solid content,protein content and urease activity of Lycium barbarum soybean milk were determined.Among them,the protein content and total solid content of Lycium barbarum soybean milk were significantly higher than the national standard.Through the study on the antioxidant activity of Lycium barbarum soybean milk and two kinds of commercially available soybean milk,it was found that Lycium barbarum soybean milk had good antioxidant activity.SPME-GC-MS was used to detect three kinds of volatile compounds in soybean milk.A total of 59 kinds of volatile compounds were detected and analyzed,including aldehydes,alcohols,ketones,alkanes,alkenes,esters and heterocycles.2-pentylfuran,1-octen-3-ol and n-hexanal were not detected in soybean milk.Therefore,the content of volatile compounds of typical beany flavor in Lycium barbarum soybean milk is low,and its beany flavor is light,which indicates that the water extract of oil-spilling Lycium barbarum has a better masking effect on beany flavor in soybean milk.