Production trials to improve the nutritional quality of biscuits and to enrich them with natural anthocyanins

The aim of the work was to improve the nutritional quality of biscuits and to enrich them with anthocyanins. The steps were (i) evaluation of various raw materials as sources of anthocyanins and optimization of anthocyanin extraction procedure; (ii) conduction of six biscuit-production trials by using anthocyanins extracted from the selected source, at different enrichment levels and with progressively less fat and sugar; and (iii) conduction of a paired-preference test to compare the best anthocyanin-enriched biscuits to control plain biscuits. Grape marc extract was selected for biscuit making. Also, the use of durum wheat semolina and extra virgin olive oil was proposed. A fat level as low as 100 g/kg was achieved, with a notable decrease of saturated fatty acids. Total anthocyanins accounted for 103x10(-3) g/kg. The color of biscuits was characterized by more intense redness and minor lightness compared to the control, and acceptability was adequate, as assessed by 103 consumers.