Preparation and characterization of jellies with reduced sugar content from date (Phoenix dactylifera L.) and lemon (Citrus limon L.) by-products

Introduction. The increase in diabetes and obesity has increased the demand for reduced sugar products such as jams and jellies. Four jelly formulations were prepared using date juice which was enriched with pectin and lemon flavors. Materials and methods. Reduced quantities of sugars (45% and 55%) were added to the juice at different pH (3 and 3.5). The prepared jellies were evaluated for physico-chemical and sensory properties. Results and discussion. The water activity values for jellies ranged between 0.767 and 0.804, making them safe from the development of the majority of bacteria. The addition of less quantity of sugar, as well as the decreased pH, resulted in significantly firmer jellies, with higher adhesiveness, chewiness and cohesiveness. Sensory evaluation showed that the prepared jellies averaged 4.17-5.47 and 4.59-5.67 for taste and firmness, respectively, in a 7-point hedonic scale consumer acceptance study. The most appreciated jellies were those prepared with the lowest sugar content, with a slight preference for that with a pH of 3.5. Significant differences were not found between scores for the other sensory attributes (color, transparency, brightness, odor and springiness).