Utilization of High Hydrostatic Pressure to Make Alginate Gels

Abstract

Alginate gel formation under high hydrostatic pressure was studied. Sodium alginate was mixed with various calcium salts and water was added to make slurry. An hydrostatic pressure of 900 MPa was applied. Calcium salts with different solubility were used, i.e. calcium chloride, calcium citrate, calcium lactate, calcium gluconate, and calcium carbonate

The texture of resultant gels varied with the calcium salts and their concentration. Both soluble and insoluble calcium salts could be used to make the gels. Calcium chloride provided an opaque, homogeneous, and firm gel. Calcium citrate provided transparent, homogeneous, and soft gel. Gel containing 15% alginate was also prepared, the concentration of this gel was 4 times higher than that of conventional alginate gels. These results suggest that insoluble calcium salts dissociate and that the hydration of sodium alginate is accelerated under high hydrostatic pressure.

It was found that high hydrostatic pressure treatment could be applied to make alginate gels. The gel can be utilized for calcium-enriched gel foods with unique textures and also as durable carriers for immobilization of microorganisms.