Development of sustainable energetic and nutritious balls based on chestnut and apple flours enriched in macroalgae from the Portuguese coast

Abstract

Macroalgae are increasingly being integrated into food, where their incorporation has contributed to an increase in its nutritional composition, namely mineral values and fibre (Gomez-Zavaglia et al., 2019; Milledge et al., 2016). This increased interest in their consumption is related to the health benefits they provide, resulting from the high number of bioactive compounds, as well as high content in polysaccharides and protein (Fradinho et al., 2019; Paiva et al., 2014). The present study aimed to develop innovative nutritious balls based on chestnut and apple flours, incorporating three macroalgae from the Portuguese coast: Porphyra dioica and Gracilaria gracilis (red macroalgae), and Ulva rigida (green macroalgal), at different concentrations (1, 3, 5 and 10% w/w). The impact of the addition of macroalgae on the rheology, nutrition, bioactivity, sensory properties (colour, smell, taste, texture and general acceptance) of the nutritious balls was studied, and the maximum level of incorporation, to understand up to what algae content the consumer accepts the product. The instrumental texture was analysed by Texture Profile Analysis (TPA), and small amplitude oscillatory shear (SAOS) measurements were carried out in a controlled stress rheometer. Colour was instrumentally measured using a colorimeter (CIELAB* system). The nutritional and chemical composition was evaluated based on the AOAC methods (lipids, ash, moisture), protein content by DUMAs methodology, and mineral profile using an ICP-OES equipment. Bioactivity was accessed by the determination of the total phenolic compounds (Folin-Ciocalteu), antioxidant activity (DPPH and FRAP assays). The obtained results showed that all the three macroalgae can be used as natural innovative and sustainable ingredients to nutritionally enrich snacks using high incorporation levels, presenting a high number of nutritional claims, namely in terms of mineral content. However, the global appreciation showed higher scores for control (4.10) than for 3% and 5% Gracilaria gracilis nutritious balls, 3.85 and 3.63, respectively