DIRECT MEASUREMENT OF BITING PRESSURES FOR CRACKERS USING A MULTIPLE-POINT SHEET SENSOR

A multiple-point sheet sensor was used to observe the distribution of surface pressure during the biting of crackers adjusted to various wat er activities. The textural characteristics were clearly reflected in the three-dimensional displays so obtained. Textural differences betwe en samples were most evident in the first 0.3 s. The magnitude, positi on and duration of biting pressure varied among subjects. For all subj ects, crisp crackers with low water activities showed a large pressure distribution with respect to both time and position. Samples with hig h water activities displayed a higher maximum force on the area under the incisors than samples with low water activities, and required more work per incision, These results are opposite to the rheometric data measured with a single-point sensor. Using this method, we could direc tly display textural differences due to the mechanical and geometrical properties of food, and could evaluate their changes in the oral cavi ty during biting.