POTATO CUBES RESPONSE TO WATER BLANCHING AND HIGH HYDROSTATIC-PRESSURE

High hydrostatic pressure treatment (400 MPa, 15 min, 5-50-degrees-C) of potato cubes (2 x 2 x 2 cm) was compared with hot water blanching (100-degrees-C, 30-180 sec). Inactivation of microorganisms and polyphenoloxidase, texture and density change, leaching of potassium and loss of ascorbic acid were monitored. Reduction of microbial counts was comparable for both methods and polyphenoloxidase was completely inactivated at 20-degrees-C, when dilute citric acid solutions (0.5 or 1.0%) were used as ''immersion'' medium. Hot water blanching and high pressure treatment resulted in samples of similar softness. Leaching of potassium was reduced 20% after pressure treatment on vacuum-packaged samples. Retention of ascorbic acid in pressure-treated samples was temperature dependent ranging from almost-equal-to 90% at 5-degrees-C to almost-equal-to 35% at 50-degrees-C.