Research On The Production Technology Of Thouin Vinegar

Thouin is a kind of fruit with homology of food and Chinese medicine. This paper manyly takes the qijiang thouin as a raw material, although it is unpalatable when fresh, it includes the multivitamins and amino acid, particularly Oleanolic Acid can reduce inflammation and transaminase active,has bacteriostasic activity, meanwhile it can promote the liver cell to regenerate,prevent cirrhosis, therefore it can be processed as a kind of function fruit vinegar. This test studys on technology of Thouin vinegar, by thouin juice using liquid state fermentation included alcoholic fermentation and acetic acid fermentation. The results play the guiding role of the Thouin vinegar's industrialization production. Thouin vinegar can be used as spice and drink.This paper mainly studied the squeezing process of thouin by means of pectinase enzymolysis,the optimization of alcoholic fermentation technical parameters,the selection of higher quality acetic acid bacteria, the determination of acetic acid fermentation technical parameters and the clarification and qualitative index of the thouin vinegar. The results as follows:1. The composition of thouin is:moisture content 84.46%,the total soluble solid content 7.8 %,reducing sugar content 2.423g/100ml,the total acid content (to malic acid meter) 2.68g/100ml,pH value 2.88,protein content 0.58%.2. The optimal squeezing condition of thouin by means of pectinase enzymolysis is:Sodium erythorbate addition 0.06%,thouin:water=1:1,pectinase 0.08%,enzymolysis pH 4.0,the acting temperature is 50℃,the acting time is 2.5h. Under this condition, the thouin extraction is 83.57%, which is 1.5 times to direct extraction (56.10%).3. Through comparison of raw wine qualitative fermented by cloudy juice,clarified juice and pulp, we determined that the cloudy juice fermentation is the best alcoholic fermentation method.4. The alcoholic fermentation technical parameters was optimized by means of quadratic general rotary unitize design. The regression equation of the four factors to alcohol content(Y) was:Y=5.41429+0.30250x₁-0.03750x₂-0.04167x₃+0.11250x₄+0.00685x₁²-0.11190x₂²-0.06815x₃²-0 .08690x₄²-0.04625x₁x₂-0.00875x₁x₃-0.04625x₁x₄+0.07500x₂x₃-0.05000x₂x₄-0.01250x₃x₄Te multiple relevance R² value of this equation is 0.9525. According to the extreme value analysis of the model, we obtained the optimum alcoholic fermentation condition, they are:the initial TTS content is 17%, pH value is 3.25, vaccination quantities is 0.08%, the fermentation time is 7 days, under this condition, the alcohol content is 6.09%. Based on the equation and the other three best parameters, the sugar content could be calculated in alcohol fermentation from the alcohol content required during acetic acid fermentation.The optimum alcoholic fermentation condition obtained by single and response surface experiment are:additive amount of SO₂ 30～50mg/L,additive amount of ammonium sulfate50mg/L,initial TTS content 17%,initial pH 3.25, vaccination quantity 0.08%,fermentation temperature 28℃,and the fermentation time is 7days.5. Trough the comparison of five kind acetic acid strains:SICC1.41, SICC1.42, AS1.41, B1 and B2 from fermentation experiment, we found that the produce acid ability of AS 1.41 is strongest. And the vinegar tastes good,has typical fruit smell and strong vinegar fragrant. So we determined that the AS1.41 is the most suitable strain of acetic fermentation.6. The acetic acid fermentation technical parameters was optimized by means of quadratic general rotary unitize design. The regression equation of the four factors to acetic acid concentration (Y) was:Y=5.41429+0.30250x₁-0.03750x₂-0.04167x₃+0.11250x₄+0.00685x₁²-0.11190x₂²-0.06815x₃²-0 .08690x₄²-0.04625x₁x₂-0.00875x₁x₃-0.04625x₁x₄+0.07500x₂x₃-0.05000x₂x₄-0.01250x₃x₄Te multiple relevance R² value of this equation is 0.9789. According to the extreme value analysis and the single experiment, the optimum acetic acid fermentation condition obtained are: initial alcohol concentration6%,initial pH value4,inoculation quantity of AS1.41 acetic acid bacteria 17.5%,temperature 31℃,volume of medium 20%,rotational speed 200r/min. In four days time, the acetic acid concentration of thouin vinegar is up to 6.557±0.06g/100 mL.7. According to the effect of different clarifications on the Thouin vinegar, the chitosan was selected as the optimal clarifier. Though orthogonal experiment,we got the optimum clarification conditions, they are chitosan amount 6g/L, clarifying temperature 25℃and clarifying time was28h.8. The thouin vinegar is yellow and shiny, the smell of vinegar and fruit is strong and have no abnormal odour. The total acid content was 6.5g/100mL. The volatilization acid content is 5.6g/100mL. The solubility solid thing is 7.0%. The deoxidize sugar is 0.2g/100mL. The gross bacteria are≤200cfu/mL. The coliform is≤3MPN/100mL. There are no dangerous bacterias.We can firstly find that Thouin can be used to ferment the good qualitity vinegar after liquor and acetification, The Thouin vinegar is a kind of seasoner, has nutritional value and the health care function.