Development And Efficacy Evaluation Of Immobilized Fermented Brown Rice Wine

As a traditional fermented wine in my country,rice wine has always used glutinous rice as the main raw material,while brown rice,as a whole grain food,has a much higher retention rate of total rice nutrition than polished rice.As a raw material for brewing rice wine,it can not only endow traditional rice wine with richer nutritional value,but also have a unique wine-making flavor.Immobilized cells bind free cells in a certain space,limit the free movement of cells,and maintain the biological activity of cells at the same time.The use of immobilized microorganisms for fermentation has great potential.Due to the single taste of traditional rice wine,the function is limited.The development of a new type of brown rice wine can not only cater to the vast number of young consumers,but also find a suitable immobilization method that is conducive to production according to different fermentation strains to make brown rice wine.Finally,a brown rice wine product with good taste and functional activity potential was obtained.This subject takes brown rice as raw material,uses immobilized fermentation technology as the core,and aims to develop a brown rice wine product with fresh flavor and rich taste.Firstly,the product quality index between immobilized fermented brown rice wine and free fermented brown rice wine was studied,and the quality difference of brown rice wine prepared by two different fermentation methods was determined;Based on this,the optimum fermentation process of immobilized fermented brown rice wine was further determined.Finally,the differences in antioxidant and antiinflammatory activities between immobilized fermented brown rice wine and ordinary commercial rice wine were analyzed and compared.The main findings are as follows:1.This paper firstly studies the similarities and differences between immobilized fermented brown rice wine and free fermented brown rice wine by studying the basic metabolite content,microbial growth and volatile flavor index of two fermented brown rice wines in two different fermentation stages.The results showed that in the first stage of fermentation,the total acid,reducing sugar,juice yield and total ester content produced by immobilized fermentation were lower than those of free fermentation,and the alcohol content was comparable.In addition,the total number of immobilized fermentative colonies was high,the enzyme activity in the fungus was low,and the enzyme activity in the extra-column system was slightly higher than that in the free fermentation system.In the second fermentation stage,the overall basal metabolites were still higher in free fermentation,and the total number of colonies in the immobilized fermentation system was still higher than that in the free fermentation system,while the protease activity was continuously decreased due to low temperature and substrate dilution.Compared with free fermentation,immobilized fermentation has higher whiteness and lower yellowness whether it is the first or second fermentation stage.The volatile substances in brown rice wine samples were analyzed by gas chromatography-mass spectrometry(GC-MS)technique.No matter in the first or second fermentation stage,esters were the highest in content and most types in the two fermentation systems,followed by alcohols.Esters and alcohols accounted for 73.24%and 17.03%in the first stage of immobilized fermentation,44.26%and 37.65%in the second stage;esters and alcohols in the first stage of free fermentation accounted for 80.06%and 16.43%,respectively.The second stage accounted for 48.15%and 35.67%respectively.2.This paper studies the step-by-step screening of different strains of targeted immobilized bead-embedding core materials,and uses sodium alginate-polyvinyl alcohol as the wall material for all prepared bacterial beads.According to the physical and chemical properties of brown rice wine in the first fermentation stage The comprehensive score of indicators and sensory evaluations screened out loofah as the immobilized bead-embedding core material for Rhizopus oryzae fermentation,and modified cotton balls or absorbent cotton balls as the immobilized embedding core material for Saccharomyces cerevisiae and lactic acid bacteria fermentation,without core material Sodium alginate-polyvinyl alcohol beads served as a control.According to the detection of volatile flavor substances in the second-stage fermentation,loofah has been used as the immobilized core material in the stage of Rhizopus oryzae.Continued screening from both modified cotton balls or absorbent cotton balls can be used for fermentation of Saccharomyces cerevisiae and lactic acid bacteria.Immobilized embedded core material.The relative contents of esters in the modified cotton ball group and the absorbent cotton ball group were 52.16%and 50.15%;the relative contents of alcohols were 25.94%and 20.88%,respectively.Compared with the modified cotton ball group and the absorbent cotton ball group,the relative content of ester substances in sodium alginate-polyvinyl alcohol bacteria beads was higher,but the alcohol substances were lower.Because the modified cotton ball group has the highest content of characteristic flavor substances such as phenylethyl alcohol and ethyl acetate.Finally,loofah-modified cotton ball was selected as the core material in the next stage,and sodium alginate-polyvinyl alcohol bacteria without core material was used as the control.In the third stage,the repeated fermentation ability was determined.Under different fermentation stages,the repeated fermentation performance of the loofah and the modified cotton balls were better than those of the core-free sodium alginate-polyvinyl alcohol bacteria beads.In the end,in this paper,sodium alginatepolyvinyl alcohol will be used as the embedding wall material of the three strains,among which the loofah is determined as the embedding core material of Rhizopus oryzae,and the modified cotton balls are used as the encapsulation of Saccharomyces cerevisiae and lactic acid bacteria.Buried core material.3.On the basis of confirming the embedding material,this paper studies the preparation parameters of immobilized and embedded bacterial beads and the optimization of the fermentation process of brown rice wine.Through the optimization test,the suitable preparation parameters of the bacteria beads were obtained as the concentration of sodium alginate is 2%(w/v),the concentration of calcium chloride is 1.5%(w/v)and the amount of polyvinyl alcohol added is 5%(w/w).In the optimization of the brown rice wine fermentation process,three main factors,namely fermentation temperature(A),fermentation time(B),and bacterial ball input(C),were used to conduct orthogonal experiments,and the comprehensive score of flavored rice wine was used as the evaluation index to finally determine the most suitable process.The fermentation temperature of Rhizopus oryzae was 28℃/3 d,the fermentation temperature of Saccharomyces cerevisiae was 30℃/5 d,and the fermentation temperature of lactic acid bacteria was 15℃/6 d.4.Finally,this paper studies the difference of antioxidant activity and antiinflammatory activity between the immobilized fermented brown rice wine product and a commercial rice wine before and after gastrointestinal digestion.The study found that by comparing the undigested samples,the brown rice wine samples were better than the commercial ordinary rice wine in four in vitro antioxidant indexes of hydroxyl radical inhibition rate,DPPH free radical scavenging ability,ABTS scavenging ability and FRAP scavenging ability at different dilution levels.However,there is still a gap in the antioxidant activity compared with the Vc positive control.After in vitro gastrointestinal digestion,the overall antioxidant activity of the digested rice wine samples was greatly improved compared with the undigested rice wine samples,and the overall antioxidant activity of the brown rice wine samples was stronger than that of the commercially available ordinary rice wine samples.It may be because after in vitro digestion,the antioxidant active substances in the sample can be decomposed and released,thereby improving the antioxidant capacity of the sample.In the cytotoxicity test of rice wine samples,there was no significant toxic effect on cells when the samples were diluted to 100 mL for 24 h and 48 h.After treatment with 1 μg/mL LPS,the contents of TNF-α,IL-6 and NO were significantly increased,indicating that the inflammation model was successfully established.For the LPS model group that has produced inflammation,after adding different dilutions of digested rice wine samples for 24 h and 48 h,compared with the LPS group,the levels of TNF-α,IL-6 and NO concentrations decreased significantly.And after 48 hours of treatment with digested rice wine samples,the degree of inhibiting the secretion of inflammatory factors TNF-α and IL-6 between brown rice wine and ordinary rice wine also showed a very significant difference between the dilution ratios(P<0.01).The results showed that compared with the LPS group,the rice wine samples could significantly reduce the secretion of TNF-α,IL-6 and NO.Compared with the ordinary rice wine samples,the brown rice wine samples had a stronger ability to reduce the release of cellular inflammatory factors and had a higher anti-inflammatory effect.inflammatory potential.