Microstructure of high-pressure vs. atmospheric frozen starch gels.

摘要

The aim of this study was to find out whether the ice crystal size of a starch gel, a model food system, could be reduced by high-pressure freezing compared with freezing at atmospheric pressure. The size and number of pores in thawed gels was determined by light microscopy and image analysis, and was taken as an indirect measure of ice crystals formed during the different freezing processes studied. The pore size and the total area occupied by the pores were clearly reduced by high-pressure freezing at 150-240 MPa compared with freezing at atmospheric pressure at the same cooling rate. The pore size in the high-pressure (nor in the atmospheric) frozen gels did not increase during a storage time of 3 months at -24 degrees C (still air) at atmospheric pressure..