Freeze Concentration of Some Foodstuffs Using Ice Nucleation-active Bacterial Cells Entrapped in Calcium Alginate Gel

Abstract

Cells of an ice nucleation-active strain of Erwinia ananas were entrapped in calcium alginate to prepare an ice-nucleating gel usable as ice nuclei for freeze concentration. The ice-nucleating gel was also adjusted as to specific gravity. When it was placed at a desired position in a liquid material such as egg white, ice formed at this position as the material was cooled. It was possible to put the icenucleating gel in liquid foodstuffs such as egg white and lemon juice before their temperatures reached subzero points. Application of this method produced freeze-concentrated foods whose properties were not significantly deteriorated.