Effects of cryoconcentrate blueberry juice incorporation on gelatin gel: A rheological, textural and bioactive properties study

Abstract

Abstract Cryoconcentrate blueberry juice (CBJ) at different concentrations was incorporated into gelatin gel and the effects on rheological and textural properties, total bioactive compounds (TBC) and antioxidant activity (AA) were evaluated. Specifically, CBJ at 20 g/100 g reinforced the gel structure, since the sample showed the highest gelling (15.0 °C) and melting temperatures (27.4 °C) in comparison to the other samples. Additionally, this CBJ concentration had an increase of 28%, 46%, 47% and 54% in relation to the initial gel strength, hardness, gumminess, and chewiness, respectively. In TBC and AA terms, the values were close to 55 mg GAE/100 g, 4.5 mg C3G/100 g, 18 mg CEQ/100 g, 42, 29 and 738 μmol TE/100 g, which are equivalent to 18%, 11%, 14%, 8%, 3% and 32%, for total polyphenol, anthocyanin and flavonoid contents, 2,2-diphenyl-1-picrylhydrazyl (DPPH), ferric reducing antioxidant power (FRAP) and oxygen radical absorbance capacity (ORAC) assays, in relation to the initial CBJ value, respectively. Scanning electron microscope images revealed that the CBJ-gelatin gels formed a structural network with porous and thick walls. Therefore, CBJ has the potential to be an excellent ingredient to add during gelatin gel preparation since it delivers bioactive components without affecting the rheological and textural properties.