Study On Black Currant Postharvest Physiology And Biolygy

Black currant is small shrubs and clusters fruit trees.The fruit is the spicate berry. The fruit isnutritious which is rich in sugars， organic acids， amino acids， vitamins and minerals， the mostabundant is vitamin C content. The black currant its fresh difficulty and fresh fruit retention time isshort which severely restricted the sale of time and affect the value of the goods. To achieve theindustrial development of the black currant， We should improve black currant preservationtechniques， we must first in-depth study of the biological basis of black currant fruit storability，learn more the quality and characteristics of the black currant fruitand figure out the the black currant storability biological basis， while comparative study of blackcurrant fruit postharvest physiological characteristics is the basis of the preferred preservationtechnology.In this study， Brodtorp， Tessa， Black feng and Fourteen black currant as the researchobject， determination of good fruit rate， weight loss rate of black currant fruit， fruit firmnessand other physiological indicators， study the variation， and identify the black currant fruitoptimum storage temperature， the relationship between the indicators and black currant fruitstorage. The main findings are as follows:(1) Black currant fruit storage effect in the0℃temperature storage conditions compared to4℃and8℃and room temperature storage conditions good.(2)Black currant fruit postharvest at0℃storage， Four varieties of black currant fruit storabilityare different. Brodtorp black currant fruit is the most resistant to storage， followed by Tessa blackcurrant and Black feng black currant， the most intolerant of storage is Fourteen black currantfruit.During storage， the good storability Brodtorp black currant fruit has the lower water lossrate， Water retention ability is strong; The titratable acid content is high，speed decline， slowdecline in the sugar content， organic acid is the main respiratory substrates in the early fruitsstorage; The content of soluble protein， vitamin C， pectin and cellulose decreased faster than thepoor storability fourteen black currant. During storage， the activity cellulase enzyme，polygalacturonic acid enzyme and pectinesterase increased at first and then a downward trend，the activity of Fourteen black currant fruit enzyme increased significantly， compared withBrodtorp black currant fruit， the peak time is more early. SOD activity of Black currant fruitduring storage showed the increased then decreased and enzyme activity peaks. Compared with Brodtorp black currant fruit， the enzyme activities of Fourteen black currant changed moregreatly， metabolic instability， the enzyme activity peaks appear more early. POD activitygradually increased， but Fourteen black currant have more large variations than Brodtorp blackcurrant fruit. The activity of amylase and CAT gradually reduced， but Fourteen black currant dropfaster than Brodtorp black currant fruit. The membrane lipid peroxidation product MDA ofFourteen black currant maintain a higher level. The fruit of lipid peroxidation level is high，thesenescence speed， the storability is poor.(3) The changes of Brodtorp black currant fruit quality and the enzyme activity is basically thesame under different storage temperature conditions. With the extension of storage time， the fruitrespiration rate and good fruit rate declined. Respiration rate under0℃are always lower than4°C and8C and room temperature storage conditions， maintain a relatively low level. Good fruitunder0℃always more hign than4℃and8℃and stored at room temperature， maintain arelatively high level. The weight loss rate and shattering rate is increasing.The content of totalsugar， titratable acidity， soluble protein， VC， pectin， cellulose decreased. The activity ofcellulase， polygalacturonicacid enzymes and pectin esterase are the first to rise， peak， and thendecreased. Amylase activity gradually decreased. SOD activity showed up-peak-down "trend.POD activity gradually increased， CAT activity showed a gradual trend. The contents of MDAand and the relative electrical conductivity has been rising. Low temperature significantly inhibitthe respiration rate， reduce the rate of consumption of the substances in the fruit， and canmaintain higher protection organization activity late in the storage， help keep the black currantfruit storage quality， thus extending fruit storage period.(4) The weight loss rate， total sugar， titratable acid and so on10indicators of the Brodtorp blackcurrant fruit under0℃during storage was for statistical analysis by principal component analysis.The results show that the comprehensive evaluation index F value of black currant fruit decreasedwith the extension of storage time. The comprehensive evaluation index of black currant fruit isbetter in15days， The comprehensive evaluation index of fruit decreased rapidly after storagefor15days. Therefore， the period of maintain the Brodtorp black currant fruit quality is15days.