Soybean is one of the major agricultural cultures in the world. Recently, soybean components, especially those concentrated in coloured seed coats, have become very interesting to researchers due to its beneficial effects and a possibility to be used as dietary supplements. Compared to the seed coats of yellow soybeans, black soybeans have a significantly higher content of polyphenols which are predominantly anthocyanins and proanthocyanidins.
For food products, especially functional one, stability of active compounds during processing and storage is essential. Encapsulation is a useful tool for improving delivery of bioactives into foods. Encapsulation is a process which entraps active agents within a carrier material. The main benefits of this process are protection of actives against evaporation, chemical reactions or migration in food, controlled delivery and preservation of stability during processing and storage, prevention of undesirable interactions with other components in products and masking of an unpleasant taste during eating.
The goal of this study was to encapsulate non-extracted bioactive compounds from pulverized black soybean seed coat in order to protect and stabilize them.
The particles were prepared by electrostatic extrusion technique. Materials used for design of protective encapsulates’ shells were alginate and pectin (plain and with 15 mass% of inulin as a filler substance).
Total polyphenol content (TPC) and the radical scavenging activity as Trolox equivalent antioxidant capacity (TEAC) were determined. The particles were analysed by optical microscopy. The release studies and rehydration properties of dried particles were performed in water and phosphate buffer saline (pH=7.4).
According to results of antioxidant assays and release studies alginate-inulin particles appeared to be suitable dosage forms. The particles, rehydrated in water and buffer were highly swollen.
The encapsulated bioactives, as a black soybean seed coat, could play a significant role in increasing the efficacy of functional foods. With applied techniques for stabilization of food ingredients and development of new approaches, we will be able to improve nutritional properties and health benefits of food compounds.
Principal investigator: Prof. Viktor A. Nedović vnedovic@agrif.bg.ac.rs
