This study presents the results of conventional aqueous (CE) and non-conventional ultrasound-assisted (UAE) extractions of polyphenolic compounds from lees extracts of red wine varieties (Merlot and Vranac). The effect of ultrasound extraction time (t, s), and amplitude (A,%) from a 400 W ultrasound processor with different ultrasonic probes diameters (Ds, mm) on the amount and profile of polyphenolic compounds in the obtained extracts was investigated and compared to CE. The optimal conditions resulting in maximum extraction of phenolic compounds were: Probe diameter of 22 mm, amplitude 90% and extraction time for Vranac wine lees 1500 s and for Merlot wine lees extraction time of 1361 s. UAE proved to be significantly more effective in enhancing the extraction capacity of trans-resveratrol glucoside (30.57% to 300%), trans-resveratrol (36.36% to 45.75%), quercetin (39.94% to 43.83%), kaempferol (65.13% to 72.73%), petunidin-3-glucoside (41.53% to 64.95%), malvidin-3-glucoside (47.63% to 89.17%), malvidin-3-(6-O-acetyl) glucoside (23.84% to 49.74%), and malvidin-3-(6-O-p-coumaroyl) glucoside (26.77% to 34.93%) as compared to CE. Ultrasound reduced the extraction time (2.5-fold) and showed an increase of antioxidant potential by 76.39% (DPPH) and 125.83% (FRAP) compared to CE.

Apple and beetroot pomace flour (APF and BPF), along with two sweeteners, sucrose and a blend of sucrose substitutes (erythritol, stevia, inulin, and fructose), were simultaneously incorporated into three matrices formulated with agar, pectin, or gelatin as gelling agents. The aim was to produce jelly candies with high content of dietary fiber and dietary phenolics, and reduced energy value. The simultaneous incorporation of sucrose substitutes and pomace flour resulted in decrease of Carb:Fiber and Sugar:Fiber Ratio to extremely low values of 2.7–3.4 and 1.3–1.6 respectively, as well as in Energy:Fiber Ratio decrease to 9.2–12.3 kcal/g DF. Relative Antioxidant Capacity Index (RACI), as indicator of antioxidant potential, was calculated by assigning equal weight to Folin–Ciocâlteu, DPPH and FRAP assays applied upon in vitro digestion of 18 formulations of jelly candies. Results obtained for formulations with and without sucrose, as well as with and without APF or BPF, enabled insight into effects of pomace flour addition and sucrose substitution in each gelling matrix on functional properties. The incorporation and the substitution impact on postprandial glucose response were followed in vivo. Their superimposing resulted in glycemic index below 30 and low glycemic load. Efficiency of applied approach in functionalization of confectionery burden with energy and minimization of glucose spike represent an example of agro-residues re-introduction with the highest potential contribution to anti-obesity strategy.