Study On Accumulation Characteristics Of Flavonoids In Xiushui Huahong And Its Varying Patterns During Drying And Brewing Processing

Xiushui Huahong(C.sinensis(L.)Osbeck)is a kind of Rutaceae Citrus plant which is mainly planted in Xiushui county,Jiangxi province.The fruit of it,a characteristic citrus species worth developing,contains a variety of bioactive substances such as hesperidin,polysaccharide and narirutin,which is high in nutrition and health care.Through relevant experiments,this paper has unfolded systematic research on fruit quality,flavonoids,antioxidant capacity in Xiushui Huahong and the drying,storage and brewing of its peel,which is aimed at its fruit quality control and providing certain scientific basis for comprehensive development and utilization.Firstly,the appearance characteristics,physical and chemical properties of its fruit during different maturity were determined,and the composition,distribution,change rule and physiological mechanism of fruit flavonoids were mainly studied.Secondly,research on the quality influence of different drying methods on Xiushui Huahong's peel physical characteristics,flavonoids substance content,oxidation resistance,volatile flavor compounds and so on were studied,focused on the research of hot air drying dynamics and quality characteristics,on the basis of it we investigated the quality influence of simulated accelerated processing on Xiushui Huahong peel.Eventually,leaching characteristics of flavonoids during brewing processing of Xiushui Huahong peel and volatile flavor components of Xiushui Huahong peel tea were studied.The main results are shown as following:?In the process of being mature,the physical quality of Xiushui Huahong fruit,such as transverse diameter,longitudinal diameter,total weight,peel weight,pulp weight,fruit seed weight,edible rate,L*,a*,b*,a*/b*,CCI value and so on,were on the rise trend,the peel was green and the fruit was oblong.The moisture of peel and pulp were between72.05%?78.86%and 86.15%?88.87%respectively.Fruit soluble sugar and solids gradually accumulated,in this process peel was dominated by reducing sugar accumulation and pulp was dominated by sucrose accumulation.Also,when the titratable acid of peel and pulp decreased,the p H value and solid acid ratio gradually increased.Soluble protein content,total amino acid and carotenoid content of pulp increased gradually,moreover the content of peel was significantly higher than of pulp.The content of vitamin C in peel and pulp increased first and gradually decreased later,but the crude fiber content of pericarp and pulp gradually reduced,Combining with appearance and physical quality of Xiushui Huahong fruit in the local traditional harvest time,fresh eating-quality of Xiushui Huahong fruit was poor,we should exploit it from the angle of processing.?Total flavonoids,hesperidin were mainly accumulated in the peel of Xiushui Huahong fruit,its pulp's were less.And with the increase of fruit maturity,the content of total flavonoids,hesperidin in peel and pulp both gradually tended to reduce.Nevertheless,the total flavonoids economic yield of single fruit was maximum on September 23^rd,hesperidin economic yield of single fruit was maximum on October 15^th.Relevant enzyme in peel and pulp of Xiushui Huahong,such as G6PDH,PAL,C4H,4CL,CHI,POD and PPO,showed a trend of decrease in activity,and peel's enzyme activity was obviously higher than pulp's.According to the analysis,it showed that the PAL and CHI may be the key to accumulation of flavonoids,not only POD and PPO involved in the degradation of flavonoids,but they could promote the accumulation of flavonoids by regulating synthetase activity.However,during fruit ripening,weakened synthetase activity was the main reason for the lower content of total flavonoids,hesperidin in peel and pulp.In the same time,the ability of removing DPPH,OH,ABTS⁺free radical and reducing power showed a gradual decline in the law with the increase of maturity.Analysis showed that total flavonoids,hesperidin are the main bioactive ingredients for Xiushui Huahong fruit.?Physical characteristics,flavonoids content,antioxidant capacity,volatile flavour composition,drying rate and drying energy of Xiushui Huahong peel from different drying methods both showed some differences.Each Xiushu Huahong peel had its own quality characteristics,VFD Xiushui Huahong peel owned the highest content of total flavonoids and hesperidin,VD Xiushui Huahong peel showed loose structure,the number of volatile flavour compounds in MD Xiushui Huahong peel was most,including 29 species.In the actual process of drying process,we should determine the suitable drying method according to the production requirement for improving product quality.?Xiushui Huahong's peel hot air drying process was divided into three periods,which were acceleration period,constant speed period and descending period.As drying temperature increased,the drying rate of peel distinctly increased.Data fitting showed that Page model can accurately describe Xiushui Huahong's drying process in different hot air temperature.Moreover,the different processing parameters of same drying method had certain influence on the related quality of Xiushui Huahong peel.Each HAD Xiushu Huahong peel had its own quality characteristics.Water holding capacity and oil holding capacity in 50?HAD Xiushui Huahong peel were highest,the total flavonoids and hesperidin content were the highest in Xiushui Huahong peel of 60?HAD,but Xiushui Huahong peel of 90?HAD showed stronger antioxidant capacity and its number of volatile flavour compounds was most.In the actual drying process,we should determine suitable drying temperature according to the enterprise production needs.In the process of simulation acceleration,its peel total flavonoids content gradually rised with the extension of processing.In the meantime,hesperidin content firstly increased and then decreased,the capacity of removing DPPH,OH,ABTS⁺free radical and reducing power was a trend of gradual increase,besides the species of volatile flavor compounds showed a trend of increase and the relative content of D-limonene showed a trend of decrease,the results showed that dried Xiushui Huahong peel should be required to storage for a certain period of time in a suitable environment for giving full play to its better edible and medicinal value.?The ratio of material to water,water quality,brewing temperature,brewing time and brewing frequency can affect Xiushui Huahong peel's extraction of total flavonoids.When brewing it on condition that the ratio of material to water was 1:125 and water quality was mineral water,the leaching amount of total flavonoids was the highest.The increase of brewing temperature can promote the leaching of total flavonoids.As the extension of brewing time,the leaching amount of total flavonoids in its pericarp always firstly rose fast and then gradually kept stable.At the same time,along with the increase in number of brewing,the leaching amount of total flavonoids in its peel were in a trend of reducing.In the tea which contained the peel of Xiushui Huahong,39 kinds of flavor substances had been identified,among them with D-limonene relative content to highest level.Besides,volatile flavor substances mainly included 6 kinds of compounds,such as terpene alkenes,alkanes,alcohols,aldehydes,esters and ketones,mostly terpene alkenes and alcohols.