The influence of storage period on variation of phenolic content in sweet cherries

Abstract

The paper deals with bio-compounds preservation in soft fruits during storage in order to allow their consumption in off-season. The work addresses sweet cherries, the most popular consumed fruits in countries across the temperate regions like Romania, which the consumer can enjoy only in May-July period. Consequently, the aim of the study was to evaluate the influence of storage conditions on the yield of biologically active compounds. In this respect, the content of total phenols and flavonoids, and free radical scavenging activity have been analyzed in order to enable consumers to choose the most efficient storage method. The best characteristics cultivar offering the potential prospects for growers is also highlighted. Sweet cherries provided by ‘New Star’, ‘Celeste’ and ‘Giant Red’ cultivars were stored for 7 days in refrigerated and freezing conditionsand then subjected to the extraction method with hydrochloric acid in methanol. Using Folin-Ciocâlteu method total phenols content of the extracts was determined. The flavonoid content was identified using an adapted method based on rutin as reference sample. The free radical scavenging activity(EC50)of the extracts was determined using stabile 2,2 diphenyl-1-picrylhydrazyl radical. The results showed that high phenols and flavonoids contents are in ‘N Star’ cultivar (0.144 g in fresh fruits and 0.129 g refrigerated ones) while the free radical scavenging activity is better conserved in frozen fruits from ‘Celeste’ cultivar (5.94 mg/mL).