Functional properties and bioaccessibility of alginate based phycocyanin-honey hydrogels
Oya Irmak Şahin, Kubra Uzuner, Ayşe Neslihan Dündar, Mahmut Ekrem Parlak, Latife Betül Gül, Adnan Fatih Dağdelen, Furkan Türker Sarıcaoğlu, Şenay Şimşek
Abstract
Food gels have become attractive due to their biocompatibility, environment-friendly characteristics, and wide array of medical and food applications. One of the main design principles of a functional food matrix is the encapsulation, protection, and controlled release of nutraceuticals. The present study utilized two products having great interest recently, phycocyanin and honey, which were embedded in a gel-type delivery system composed of different concentrations of alginate (0.5, 1.0, 1.5, and 2.0g/100 mL) and gelatin (7g/100 mL). The phycocyanin-honey gel balls (PHB) were characterized in terms of physical, rheological, textural, morphological, and sensory properties, as well as in vitro digestion, bio-accessibility, and total phenolic content release kinetics. The increasing alginate concentration significantly increased (p<0.05) total phenolic content. Also, increasing alginate ratios caused sheet-like inner layers observed in scanning electron microscopy (SEM) images. In vitro digestibility of phenolic content derived from both honey and phycocyanin was significantly improved (p<0.05) and protected from the mouth and gastric medium by hydrogel structures of alginate and gelatin. PHB showed high release (>≈85g/100 mL) and bio-accessibility (>≈84g/100 mL) of phenolic content in the intestinal medium. Consequently, alginate could be successfully used at 1.5g/100 mL concentration with gelatin to enhance the functionality and bio-accessibility of functional ingredients without affecting sensory properties.