Effect of the Addition of Apple Pomace and Erythritol on the Antioxidant Capacity and Antidiabetic Properties of Shortbread Cookies

Abstract

Apple processing into juice generates vast amounts of a by-product, namely fruit pomace, which poses a serious problem for the processing industry. At the same time, fruit pomace features a high health potential. The aim of the present study was to develop recipes of 8 variants of cookies with wheat flour substituted by apple pomace (0, 10, 30 and 50% of flour weight), sweetened with sucrose and erythritol. The cookies were analyzed for their nutritional value; antioxidant capacity (ABTS•+ scavenging activity and oxygen radical absorption capacity – ORAC); the ability to inhibit α-amylase, α-glucosidase and pancreatic lipase; and consumer acceptability. In total, 13 phenolic compounds were identified in the cookies with pomace. Cookies with 50% addition of apple pomace had an approximately 8-fold higher content of dietary fibre than traditional products (without the apple pomace) and simultaneously reduced energy value (by 32.6 and 40.5 kcal/100 g of cookies sweetened with sucrose and erythritol, respectively). The antioxidant capacity of cookies was 0.032–0.316 mmol TE/100 g in the ABTS assay and 1.153–2.070 mmol TE/100 g when ORAC was determined. The IC 50 enabling α-amylase and α-glucosidase inhibition ranged from 138.1 to 221.8 mg/mL and from 976.4 to 1374.9 mg/mL, respectively. The anti-lipase activity of cookies with the addition of 50% apple pomace and erythritol was the highest (IC 50 of 7.3 mg/mL). Both antioxidant capacity and antidiabetic potential increased significantly with the increasing proportion of pomace in cookies. Replacing sucrose with erythritol favorably influenced the consumer assessment. The study results show that the proposed products can be a perfect alternative to traditional sweet snack products, especially for consumers with diet-related diseases. The feasibility of using waste raw materials, which are a challenge to the food industry, has been proven as well.

Keywords

• apple pomace
• erythritol
• shortbread cookies
• lc-ms
• antidiabetic activity
• antioxidant activity