A RESEARCH ON RASPBERRY AND BLACKBERRY MARMALADES PRODUCED FROM DIFFERENT CULTIVARS

Abstract

ABSTRACT In this study, the changes in color, ascorbic acid, antioxidant activity and phenolic compounds of raspberry and blackberry cultivars after marmalade processing were evaluated. For this purpose, raspberry fruits (Rubus idaeus L.) of four cultivars (Aksu Kırmızısı, Rubin, Hollanda Boduru and Heritage) and blackberry fruits (Rubus fruticosus L.) of three cultivars (Bursa 1, Bursa 2 and Chester) were used. According to the results, color values of blackberry cultivars and marmalades were lower than the color values of raspberry. Raspberry cultivars were more durable to thermal processing than blackberry cultivars in terms of ascorbic acid degradation. An 84.19% decrease was seen in the antioxidant activity of raspberry and blackberry cultivars after marmalade processing. The marmalade produced from Hollanda Boduru had the highest antioxidant activity. Ellagic acid was predominant in all raspberry and blackberry cultivars and ranged from 727.90 ± 9.21 mg/kg (Rubin) to 1,828.07 ± 23.73 mg/kg (Chester). None of the phenolics was determined in marmalades. PRACTICAL APPLICATIONS Berry fruits constitute a good source of natural antioxidant substances. Particularly, phenolic compounds contribute substantially to the antioxidant complement of many small fruit species, having potential health effects. The main contribution of this work is to determine the compositional changes of different blackberry and raspberry cultivars after marmalade production.