Blueberry polyphenol-protein food ingredients: The impact of spray drying on the in vitro antioxidant activity, anti-inflammatory markers, glucose metabolism and fibroblast migration

Wild blueberry pomace extract complexed with wheat or chickpea flour or soy protein isolate produced spray dried and freeze-dried polyphenol-protein particles. To evaluate the impact of spray drying on the biological activity of these food ingredients in vitro antioxidant and anti-inflammatory activities, regulation of glucose metabolism and ability to stimulate fibroblast migration were tested. Extracts from polyphenol-protein particles significantly decreased reactive oxygen species (ROS) production and down-regulated the gene expression of inflammation markers (COX-2 and IL-beta). Milder suppression of nitric oxide production and inducible nitric oxide synthase (iNOS) gene expression was evident. The extracts significantly inhibited phosphoenolpyruvate carboxykinase (PEPCK) and accelerated fibroblast cell migration up to 3-fold after 24 h. Complexed polyphenols retained their structural integrity and bioactive potency for both lyophilized and spray dried treatments. The data suggests that spray drying is a convenient and cost-effective technique to produce blueberry-polyphenol food ingredients with preserved phytochemicals with biological activities.