Research On The Brewing Technology Of Xuehua Pear-loquat Leaves Compound Fruit Wine

With the changes in national consumption concepts and drinking habits,the alcohol market puts forward requirements to strengthen the nutritional and functional properties of fruit wine,and advances the identification and promotion of specialty fruit wine products and production areas.Currently,pear wine has some problems such as lacking of dedicated fermentation strains,single brewing process,weak flavor and insufficient functionality.Fruit wine brewing technology and traditional Chinese medicine processing technology were combined to develop a new type of compound health fruit wine.Traditional Chinese medicines of the same food and medicine was added to Xuehua pear juice for raw material compounding.Adopting mixed fermentation,Saccharomyces cerevisiae and Lactobacillus were used as fermented strains.The main research achievements are as follows:Firstly,Saccharomyces cerevisiae XH,Lactobacillus plantarum L.p 01,Lactobacillus paracasei L.p 02 and Bacillus licheniformis B.l which had excellent fermentation performance were isolated from orchard soil,Xuehua pear fermentation broth and probiotic preparations.The highest total flavonoid content in the fruit wine containing Xuehua pear and loquat leaves was 3.36 mg/m L,which was 7.64 times higher than Xuehua pear wine.The growth and metabolism of the strain combination XH and L.p 01in the mixed fermentation broth both were the best.But the simultaneous inoculation method reduced the viable cell count of the strains in the middle and late stages of fermentation.Secondly,in order to reduce the antagonism between strains in the middle and late stages of fermentation,increase the antioxidant capacity of the pear wine,and improve the flavor of the pear wine,the two-stage fermentation method was used to brew the Xuehua pear-loquat leaves compound fruit wine.The composite fruit wine,culturing L.p 01 for 24hours and then inoculating with XH for alcohol fermentation,had the best antioxidant capacity.The total flavonoid content in the wine was 0.66 mg/m L,the total phenol content was 0.45.mg/m L,DPPH clearance rate was 21.49%and Fe³⁺reducing power was 0.858.The content of organic acids in fruit wine increased.The content of lactic acid,tartaric acid and acetic acid were the highest,which were 167.84,9.87,and 7.56 mg/L,respectively.There were 62 kinds of volatile components which increased significantly in fruit wine.Finally,the electronic nose and electronic tongue were used to measure and analyze the compound pear wine in order to establish an objective and efficient new sensory evaluation method.The evaluation formula of the electronic nose for the comprehensive value of the sample aroma:z F=96.246%×(-0.103x₁+0.101x₂-1.103x₃+0.103x₄-0.103x₅+0.098x₆+0.098x₇+0.103x₈+0.101x₉+0.103x₁₀).The evaluation formula of the electronic tongue for the comprehensive value of the sample taste is z F=98.8%×(0.986x₁+0.978x₂+0.978x₃+0.951x₄-0.827x₅-0.781x₆+0.777x₇-0.017x₈-0.644x₉)+1.0%×(0.025x₁+0.092x₂-0.174x₃-0.155x₄+0.176x₅-0.571x₆+0.511x₇+0.792x₈+0.746x₉).Through stepwise discriminant analysis,the electronic nose and electronic tongue could completely distinguish the aroma and taste of the sample.In addition,by establishing a neural network model,the content of ethanol,titratable acid and reducing sugar in pear wine could be quantitatively predicted.