The investigation of the effect chitosan on the quality parameters of Ribes Nigrum L

Abstract

Blackcurrant (Ribes nigrum L.) is a shrub commonly grown in various parts of the world in temperate climate. The blackcurrant berries are known to have high nutritional value, high level of polyphenols, anthocyanins, phenolic acids, flavonols and proanthocyanidins. In previous studies of polyphenolic compounds in blackcurrant it was determined, that highest level of total phenolic compounds, flavonoids and radical scavenging activity is found in berries of polyploid plants, which were collected at the end of fruit harvesting period. The shelf life of blackcurrant berries is short (two days), therefore extending the shelf life is investigated in this study. Blackcurrant berries were coated with different molecular weight chitosan, which is considered as a natural preservative for extending the shelf life of sensitive fruits. During the shelf-life period for determination of physico-chemical and nutritional parameters following methods were used: (i) titration for the content of vitamin C and for (ii) the anthocyanins, (iii) spectrophotometry for the phenolic compound content, (iv) refractometry for determination of total solids, (v) pH change of the juice, (vi) micro-dynamometry for the firmness of berry peel and (vii) weighting method for the mass loss during the shelf life period. The chitosan coating improved the quality of the blackcurrant berries with respect preservation of to vitamin C content, anthocyanins, polyphenols and user-acceptable firmness. Specific details and problematics will be discussed during the conference. The chitosan coating can be used to extend the shelf-life of the berries of blackcurrant.