Thermal, antioxidant, morphological and bioactive properties of starchy material extracted from the bacupari (Garcinia brasiliensis (Mart.)) seed using aqueous and alkaline maceration

Despite their being rich in bioactive compounds, by-products produced during fruit pulping are usually discarded. The present paper aimed to investigate the potential of bacupari seeds (Garcinia brasiliensis (Mart.)) as an alternative source of starchy material extracted in aqueous and alkaline conditions, as well as the flour from bacupari seed by-products (BSB) generated after each extraction. Bacupari seed starchy material (BSS), obtained from seeds of unripe (UN) and ripe (RI) fruits, as well as their BSB were characterized according to their physicochemical, antioxidant (DPPH, ABTS, FRAP), microstructural (SEM, XRD), thermal (TGA, DSC) and pasting properties (RVA), as well as their physical properties (hygroscopicity, wettability and solubility) and bioactive compounds (UPLC) and FTIR. The micrographs revealed that both UN and RI starchy material from alkaline maceration resulted in granules having smoother surfaces and more oval characteristics. The seeds from immature fruits resulted in starchy material with a lower amylose content, which in turn resulted in greater crystallinity and peak viscosity. The extraction methods and maturation stages affected gelatinization temperatures and enthalpies. The starchy material sample obtained from ripe fruits submitted to water maceration exhibited greater thermal stability, an observation that can be attributed to the higher amylose content and lower degree of crystallinity, resulting in a stronger interaction with the other components. The results obtained made it possible to verify that the seed can be used as a raw material for isolating an unconventional starchy material that shows potential as an antioxidant and bioactive material whose properties make it ideal for insertion into the food industry for use in industrial thickeners, gelling agents, as well as main macromolecules of biodegradable and edible films. Moreover, both BSS and BSB exhibited antioxidant activity, meaning that the BSB by-product may also be inserted in the industry.

Automated summary

This study investigated the potential of bacupari seeds as an alternative source of starchy material and characterized the properties of bacupari seed starchy material and its by-products. The results showed that bacupari seeds can be used to extract unconventional starchy material with antioxidant and bioactive properties.