Study on liquid core barberry (Berberis vulgaris) hydrogel beads based on calcium alginate: Effect of storage on physical and chemical characterizations

Abstract

Production of barberry hydrogel beads containing suspended pulp was investigated based on reverse spherification method. Beads with different concentration of sodium alginate (0.5%, 0.8%, and 1% w/v) and calcium lactate (1%, 1.67%, and 2.2% w/v) were prepared. Total phenolic content (TPC), antioxidant capacity, membrane thickness, microstructure, hardness, and thermal properties of beads were evaluated at the time of production and after two months of storage. Textural studies indicated that an increase in sodium alginate concentration, improved hardness (from 67.2 to 207 g) of liquid hydrogel beads and reduced the destruction of antioxidants and total phenolic contents during storage. Calcium lactate concentrations had an adverse effect on hardness of hydrogels. Evaluation of micrographs confirmed a significant difference between the network structures of hydrogels containing various concentrations of calcium ions. TPC contents of the sample containing the highest concentration of sodium alginate were higher than beads containing 0.5% and 0.8% sodium alginate. Practical applications As a result of this paper, we will be able to fabricate a method to produce hydrogel beads filled with barberry syrup. This product can be easily consumed as a nutritional snack by people of different ages. This product will be interesting for children due to its unique mouthfeel as the liquor in the beads bursts into the mouth with teeth pressure. Protection of the nutritional properties of herbal extracts using reverse spherification method will be possible as a result of our developed method, which can be applied for different products in the future.