Study On Fermentation Process And Bitterness Substances Of Citrus Wine

This study took the citrus as raw material,researched the optimal fermentation conditions,detected limonin and nomolin by high performance liquid chromatography,compared the effect of three different methods of removing bitter citrus wine.The main objective was to provide scientific and technical support for developing and to promote citrus wine.The main results were as follows: 1?Fermentation techniques of citrus wineThe pretreatment methods and fermentation strains were selected for the fermentation of citrus wine.The optimal fermentation conditions were explored by single factor and orthogonal experiments.The best fermentation conditions were obtained as follows: using citrus juice,inoculated SC wine yeast,total sugar for 24%,inoculation amount for 0.04%,and fermented at 26 ? for 6 d.Under these conditions,the alcohol of the wine was 12.4%vol,the sensory score were 83 points,and the citrus wine is golden,clear and bright,with a typical aroma,the physical and chemical indicators meet the national standard requirements 2?The main content and method for the determination of bitter substances in citrus wineTo establish an Reversed High performance liquid chromatography(HPLC)method to determine the content of limonin and nomilin.Limonin and nomilin were separated by Agilent ZORBAX SB-C18 column(4.6×250mm,5?m)with acetonitrile-0.1% phosphoric acid water(45:55,V:V)as the mobile phase,the column temperature was 35 ?,the flow rate was 1.0 m L·min-1,the detective wavelength was 210 nm.The two compounds were effectively separated and determined in 7 minutes.The Calibration curve were good linear in the range of 0.86-34.4mg/L for limonin and 0.92-18.4 mg/L for nomilin.The average recovery of limonin and nomilin was 100.83% and 95.88%.The results show that the method is accurate,reliable and effective.The contents of limonin and nomilin in citrus wine were 12.878mg/L,10.023mg/L.3?Study on the process of citrus wine bitter removingThe ?-Cyclodextrin,naringin,X16 resin were added to citrus wine,the loss rate of limonin,nomilin and vitamin C were as the evaluation index,It is found that X16 resin on the citrus wine bitter effect of the best.According to the research,the best debitterize conditions were as follows: the resin usage was 4%,adsorption temperature was 25?,adsorption time was 25 min,rotation speed was 100 r /min,the debittering rate of limonin and nomolin were 49.54%,33.69%,the vitamin C loss rate was 25.12%.The bitter substance is reduced to a bitter threshold and is suitable for drinking.