Discrimination of cucumber cultivars using a multiple-point sheet sensor to measure biting force

To define the textural differences among three cucumber cultivars, we combined two different mechanical measurements: a direct measurement of mastication force using a multiple-point sheet sensor (MSS), and a uniaxial compression test. For mastication force measurement, subjects bit a sample placed on the sheet sensor with their upper and lower incisors. During a single bite, masticatory force was measured using a computerised MSS device called the ISCAN system with a TSCAN sheet sensor. Values of maximum bite force, the time at which maximum bite force appeared, area under the force-time curve, contact area and maximum pressure point for one cultivar were significantly higher than those for the other two. For all the parameters, lower values corresponded to crispness and higher values to toughness. Overall tendencies were the same in the compression test, though the compression test tends to yield smaller standard deviations. The MSS masticatory test is suitable for analysing masticatory properties with respect to each individual, while the instrument test is suitable for analysing physical properties inherent in each sample. Combination of the actual mastication test performed in the human oral cavity and conventional mechanical tests provides the most reliable objective analysis of food texture.