Preparation and Characterization of Tamarind Gum/Sodium Alginate Composite Gel Beads

A two-step preparation and the characterization of composite gel beads of tamarind gum (2.0 wt%) and sodium alginate (0.6 wt%) as spherically well-shaped forms are reported. In the first step, the prepared solution containing tamarind gum and sodium alginate was extruded as small drops by means of syringe into a stirred calcium chloride (CaCl2, 3.0 wt%) at 4 degrees C and then in the second step the beads were soaked in solidified agent solution (Na2B4O7, 2.0 wt%). Thus, we obtained composite gel beads with diameter range between 2 and 3 mm. We have demonstrated the properties of the composite beads, such as morphological, thermal stability and functional groups characterized by different techniques (i.e., SEM, DSC, and FTIR). The swelling behaviour in response to pH variation as well as the mechanical strength of the composite gel beads are examined and reported. The results have demonstrated that the composite gel beads not only have the advantages of rather rough surface, three-dimensionally network structure, and high anti-acid and anti-alkali properties, they are not prone to breakage under load. The composite gel beads prepared are potentially useful as polymeric carriers or supports in biotechnology and biochemistry applications.