International journal of food science and technology vol:35 issue:3 pages:331-340
Eight mechanical properties of three potato cultivars were measured during low-temperature blanching (55, 65 and 75 degrees C) and subsequent cooling and cooking treatments. The mechanical properties were determined with a ring tensile test. Force-based properties showed a decrease in value during blanching and cooking, whereas deformation-based properties showed an initial increase during blanching, before decreasing, during cooking or after longer blanching times. This behaviour was attributed to the loss of turgor of the fresh potato tissue. Rates of change of mechanical properties during cooking depended on the pre-blanching treatments: longer blanching times resulted in a slower decrease of the mechanical properties. The overall behaviour during blanching and cooking of the three cultivars was similar. A principal component analysis on the measured mechanical properties, for each blanching temperature separately, was used to study the blanching temperature effect and to segregate potato cultivars on their cooking behaviour.