Valorisation of grape skin and seed, as industrial waste, in some confectionery products as bulking agent and source of bioactive compounds

Nowadays, the use of plant-based by-products obtained after food processing has gained importance, as these products are nutritious and cheap. One of the aim of this study was to determine the effects of grape skin and seed powders with different particle sizes (100, 200, 288 and 415 μm) on the texture, sensory, color, and rheological properties of soft candies. In conclusion, it was shown that grape-derived components can be successfully used in the formulation of soft candy if particle size was adjusted below 200 μm. Another aim was to apply grape pomace (GP), a processing sidestream comprising of grape skins and seeds that are rich in dietary fibers and polyphenols, in wafer sheet at different concentrations [5.00 (GP5), 10.0 (GP10) and 15.0 g/100 g (GP15)] for the partial replacement of wheat flour (WF) and improve the functionality of wafer sheets and it is concluded possible to partially replace the WF with GP at a concentration of 5.00 g/100 g in wafer to develop wafers having higher functionality and nutritive content. Last aim of the study was to use grape pomace (mixture of grape seeds and skins) powder (GPP) in the white chocolate formulations at different concentrations [10.0 (GPP10), 20.0 (GPP20) and 30.0 (GPP30) g/100 g] for the purpose of partial replacement of sucrose. Considering the low cost and high bioactive content of GPP, possible utilization in white chocolate formulations would have advantages in terms of both consumer demands and environmental issues. In conclusion, instrumental and sensorial results showed that it is possible to partially replace the sucrose with GPP at a concentration of 10.0 g/100 g in white chocolate.