| As an old and emerging wine,foamed wine is not only suitable for various occasions,but also used as an aperitif.It is becoming more and more popular with the early drinkers and young people.The low degree bubbling wine is a new variety of wine which is popular in Europe and America in recent years and is called the future of the world wine.At present,the production of blisters has a small scale and high cost,and the advantages of the pot production are outstanding,the production cycle is short,the operation is simple and the benefit of the liquor is more industrialized.In this study,a non-saccharomyces was isolated from Kombucha,and mixed with commercial Saccharomyces cerevisiae,fermented by secondary fermentation in tank fermentor,and made from Ningxia’s advantageous agricultural product resources,grapes,medlar,sea buckthorn,and Ou Li as auxiliary materials.The grape compound juice was prepared,and low alcohol sparkling wine was developed.The indexes of the product were determined.The experimental results are as follows:(1)53 yeast strains with typical characteristics were separated from Kombucha fermentation medium,and9 non Saccharomyces cerevisiae were tested by tolerance test and fermenting performance test.On this basis,the sensory evaluation and the determination of alcohol production capacity were further carried out,and a non brew yeast H8 with good tolerance and good fermentation performance was finally obtained.(2)In the preparation of compound grape juice,a single factor test was conducted to determine the amount of glutinous juice added,the amount of eucalyptus juice added,the amount of sea buckthorn juice added,and the initial sugar content.The orthogonal test was performed according to the results of the single factor test to obtain the optimal combination.10%of Lycium chinensis fruits juice,9%juice of Cerasus humilises fruits juice,3%of sea buckthorn fruits juice,adjusted sugar content of 23°Be’.The sensory evaluation score reached 87.5 points under the optimal combination.The pH of the system was 3.41.(3)Two stage fermentation conditions were optimized by Box-Behnken design and analysis of variance.The microbial populations in Kombucha medium were analyzed,and the fermentation broth that had been cultured until the 4th day was used as a seed solution for compound grape juice fermentation.The results show that kombucha inoculation amount was 7%,fermentation temperature was 30℃ fermentation time was 4d,pH was 3.41,retained fermentation broth residual sugar 13°Be’,to ensure the secondary fermentation during the first fermentation.The second fermentation optimization results:mixed bacteria inoculation amount of 7%,non-saccharomyces cerevisiae inoculation ratio of 65%(non-Saccharomyces:Saccharomyces cerevisiae ratio of 13:7),fermentation temperature of 12.5℃,fermentation time 5d,the end of fermentation alcoholicity At 5.02%Vol,the residual sugar was 4.48°Be’,the pressure in the tank was maintained at 0.14 MPa,the temperature was lowered to 4℃,and sulfuric acid was added to prevent the contamination of the bacteria.The physical and chemical indexes of the product were:residual sugar 44.2g/L,alcohol content 5.01%Vol,CO20.14%(0.14MPa),free SO 237mg/L,total acid content 6.21g/L,dry extract 46.4g/L.(4)The volatile aroma components of the product were determined and analyzed by headspace solid phase microextractions and gas chromatgraphy mass spectrometry.A total of 44 volatile substances were detected,of which 33 were esters and 7 were alcohols.The total relative content of acids,ketones,aldehydes,and phenols was 78.08%;the calcium content of the product was 1.58 mg/100 g,the Vc content was 73 mg/L,and the total flavonoid content was 47.28.The mg/L polyphenol content was 458.25 mg/L,and the DPPH radical and ABTS radical scavenging rates were 79.29%and 51.94%,respectively.In summary,the compound low alcoholic sparkling wine is a good product with rich nutrition,good sensory and aroma,suitable for most consumers to drink. |
