Enrichmet of cakes with elderberry extract : Effects of different formulations on bioactive properties and cake quality

Abstract

Cake varieties differ due to formulation and production methods. Numerous studies have focused on enhancing the bioactive properties of bakery products by adding various fruit extracts. However, due to variations in formulations, significantly different results particularly in terms of bioaccessibility are obtained. In this study, elderberry (Sambucus nigra L.) (EB), a berry known for its high antioxidant capacity due to its phenolics, was used in the powdered extract form to enrich cakes. The effect of different cake formulations on the in vitro bioaccessibility of EB extract was investigated to determine the type of cake that provides the highest bioaccessibility of  EB extract. The powdered extract was added 2% to four formulations: foam-type (sponge cake), cream-type (pound cake), a mix of foam and cream type (chiffon cake), and the AACC cake formulation. Quality characteristics of the cakes (baking loss, color, texture) and batter viscosity were evaluated. Changes in antioxidant capacity were examined using total phenolic content, total antioxidant capacity, and in vitro digestion model. Control cakes without extract were also produced for each formulation and analyzed. The highest baking loss, lowest batter viscosity, and lowest cake hardness were observed in chiffon cake (p<0.05). While no significant difference was found in crumb color change (ΔE) (p>0.05) , chiffon cake showed the least crust color change (16.28) (p<0.05). When the pre-digestion samples were compared with their control samples, the sponge cake showed higher total phenolic content and antioxidant activity (ABTS and CUPRAC) than the other formulations (p<0.05). However, after intestinal digestion, except for ABTS, chiffon cake exhibited significantly higher antioxidant activity (CUPRAC: 527.83 mg TE/100g; FRAP: 186.5 mg TE/100g), total phenolic content (165.59 mg GAE/100g), and bioaccessibility index (138.82%–230.82%) compared to the other formulations (p<0.05). Findings indicate that ıncorporating elderberry extract into chiffon cake more effectively enhances bioactive properties without affecting quality