• Characteristic distance;
  • characteristic time;
  • first bite;
  • jaw movement;
  • penetration rate


Curves of three biting variables, i.e., force, teeth opening and penetration rate, against time during first bite with different foods (apple, cheese, carrot, hula hoops and biscuits) and different sample thickness (5, 10 and 20 mm) have been examined. The characteristic times and distances of incisor penetration during three stages (loading, unloading and accelerating) were investigated. Results show that the food type and sample size have significant effect on the jaw movement pattern. The mean characteristic time and distance of soft foods were longer than those of hard foods during the unloading process, but there were no obvious difference during the other two stages. For the same food, all mean characteristic parameters (except the accelerating times for apple) increase as the thickness of the sample increases. The analyses on the relationships between the different characteristic parameters and the variations of the incisor penetration rate during first bite are also presented.

Practical Applications

As an important quality attribute, texture strongly dominates food acceptability and people's choice. Understanding the mechanisms of texture perception is therefore a basic task in food science and technology. Food texture is a sensory property being perceived by human senses and influenced by the manner of food reduction in the mouth. Biting variables during first bite contain important information about the interactions between the human body and the food. The present work shows that the teeth's closing movement can be precisely managed by the central nervous system based on the mechanical properties and sample size of foods. The mechanical information used to discriminate the food types during the sensory evaluation should mainly come from the early loading stage. Some results obtained in this study may have great potential for use in the study and application of food texture science.