Effect of aronia berry honey syrup used for sweetening jams on their quality.

Abstract

The effects of sweetening agents on the quality of low sweetened jams were compared with respect to blackcurrant, raspberry, sour cherry, strawberry, and bilberry jams. The sweetening agents were sucrose, aronia berry honey syrup, and sucrose + honey syrup at a ratio of 1:1. The level of physicochemical indices, especially the content of vitamin C and anthocyanins determined directly after production and after 3- and 6-month storage, was used as the quality criterion for the evaluation of jams. Moreover, after 6-month storage the products were subjected to sensorial analysis. According to the accepted method of the investigation the produced jams were characterized by a 32-33% content of extract. During the production and 6-month storage the content of acids slightly and that of pectin considerably (from 26 to 46%) decreased, although the consistency of the jams was not affected thereby. In the case of vitamin C, its pronounced losses concerned raspberry (62-67% of the initial value), strawberry (57-61%), and sour cherry (57-58%), being distinctly smaller in blackcurrant (13-16%) and bilberry (15-35%) jams. With respect to anthocyanins a similar regularity was observed, the losses reaching 49-63% in strawberry jam, 40-56% in raspberry, 33-39% in sour cherry, 30-36% in blackcurrant, and 28-36% in bilberries. In almost all the products the losses of vitamin C and anthocyanins were higher when sweetening agent was aronia berry honey syrup. The organoleptic evaluation showed that the addition of aronia berry honey syrup to raspberry and strawberry jams slightly spoiled their colour but improved the aroma and taste. In the final score the significant differentiation in favour of the addition of aronia berry honey syrup concerned only blackcurrant, sour cherry, and bilberry jams.