Study On The Antioxidant Of Hovenia Dulcis Thund Fruit Vinegar

The fruit vinegar is more and more popular for its unique flavor, taste, nutritional valueand healthy functions. The modern research shows that the fruit vinegar possessesantioxidational effects which can prevent and treat high blood cholesterol and cardiovasculardisease.The purpose of this study was to investigate the main components of stems; thetreatment of stems in the alcoholic fermentation; the changes of the main component,antioxidants and antioxidant capacity were researched in alcoholic fermentation andacetic acid fermentation. The antioxidants and antioxidant capacity of Hovenia dulcisThunb wine, vinegar and their concentrate and distillates were analysed and compared.The antioxidants and antioxidant capacity of Hovenia dulcis Thunb wine, vinegar indifferent solvent extracts were compared and analysed in correlation with them. Themain results are as follows:(1)The main chemical compositions of fresh Hovenia dulcis Thunb stems were testedfor 51.98% moisture content, 0.7g/100mL total acid (citric acid). The total sugar was 36.51g/100g fresh weight (glucose), reducing sugar was 22.37 g /100g fresh weight (glucose), totalascorbic acidcontent was 47.43 mg / 100g fresh weight (ascorbic acid), total phenol contentwas 267.27mg / 100g fresh weight (protocatechuic acid), total flavonoid content was 185.20mg /100g fresh weight (rutin).(2)The Hovenia dulcis Thunb stems were treated in three different ways by comparingthe alcohol content, juice yield, total acidity and total Vc of Hovenia dulcis Thunb fruit wine.The indexes of crushing fermentation were higher compared with direct fermentation andenzyme fermentation.(3)The changes of indexes were tested in alcoholic fermentation. Soluble solids andreducing sugar content with time showed a slight increase at first, then sharp decline andfinally remained the same. The alcohol was slowly increased at first, then rapidly increasedand finally remained unchanged. The acidity had upward trend. pH values were stable afterthe first decline in the trend. Fluctuation in the total phenol content, the overall was upward trend. Upward trend was in total flavonoids. DPPH radical scavenging ability was enhancedwith time. Reducing power had fluctuation but no significant change.(4)The changes of indexes were tested in acetic acid fermentation. The experimentfound that the change of indexes in start-up phase was similar to the ones in rapid phase.Alcohol decreased slowly at first, then quickly, at last stayed stably; after acidity rase slowlyat first, it increased rapidly and at last stayed stably; pH value was declining slowly.Fluctuation in the total phenol content, the overall was downward trend; total flavonoidcontent was firstly decreased and then increased; DPPH radical scavenging ability decreasedwith time; reducing power was downward trend.(5)The antioxidants and antioxidant capacity of Hovenia dulcis Thunb wine, vinegarand their concentrate and distillates were analysed and compared by DPPH radical scavengingability, total phenol and total flavonoids. Hovenia dulcis Thunb wine, vinegar and theirconcentrate had strong antioxidant capacity, and theirs distillates almost had no antioxidantcapacity.(6)The antioxidants and antioxidant capacity of Hovenia dulcis Thunb wine, vinegar indifferent solvent extracts were compared and analysed. The yield of each wine extract was:water residue> butanol extract> ethyl acetate extract> chloroform extract; the yield of eachvinegar extract was: butanol extract> water residue> ethyl acetate extract> chloroform extract.The highest DPPH radical scavenging ability was in the chloroform extract. The ability in theethyl acetate extract was weaker than one in chloroform extract, and one was the weakest inthe water residues. There were the same trend between total phenolic content, total flavonoidcontent and DPPH radical scavenging capacity, which revealed phenols and flavonoids wererelated with antioxidant capacity.