Physico-chemical, sensory and volatile profiles of biscuits enriched with grape marc extract

The aim of this work was to characterize the physico-chemical, sensory and volatile profile of functional biscuits enriched with grape marc extract. Control biscuits, without the addition of extract, were produced for comparisons. The enriched biscuits showed higher phenolic content and antioxidant activity than control. Moreover, they had higher sensory scores for color (confirmed by greater values of a* and 100-L*), fruity odor, and sour taste, coupled with lower friability. The volatile analysis pointed out higher amounts of compounds derived from Maillard reaction (with the exception of pyrazines) and from lipid oxidation. The latter, imputable to the presence of grape seeds in raw materials, were far from provoking off-flavors. The principal components analysis, carried out on the volatile compounds and color data, discriminated biscuit types on the basis of the presence of grape marc extract. PC1 explained 68% of data variability.