The objectives of this study were to propose a new method for determining thermal diffusivity and to use this method to estimate the thermal diffusivity of certain foods. The thermal diffusivity of 5 samples (sucrose solutions, rough rice-packed beds, burdock, carrot, and radish) were estimated using an inverse technique. The burdock and radish were cut into cylinders prior to analysis. To examine the effects of size and shape on the diffusivity determination method, cylindrical, disk-shaped, and rectangular parallelepiped carrots were used for the measurements. Samples were heated in a water bath at 60℃ or 90℃. The 2- and 3-dimensional transient heat conduction problems were solved numerically by a finite element method using the COMSOL Multiphysics^® commercial software. The thermal diffusivity of each sample was determined by an ordinary least squares method based on the temperature profiles of the sample. The advantage of this method is that the device and the estimation method are simple. This method can be applied to the materials that have an atypical shape and size. The results obtained in this study can be utilized in the design of equipment and in calculations involved in thermal processing of certain foods.

　The vibration characteristics, contact load, and breaking strength of Satsuma mandarin stacked in a triple-wall fiberboard box under a vibration treatment (2-30 Hz, 0.6 G) were investigated for evaluating the feasibility of using a bulk container (BC) for fresh produce transportation.

　Acceleration transmissibility (AT), which is the value obtained by the acceleration of individual fruit divided by that of the vibrating table, was used as the index for vibration characteristics of BC and carton box. The maximum AT values for both BC and carton box were recorded for the top layer mandarin. This maximum value of AT of the top layer fruit, at 1,000 mm from the bottom as the maximum height for the practical use of BC, was 3.6 times of carton box.

　As for vibration load, when the number of stacking increases, BC contact load would increase with lower peak frequency.

　Breaking strength values, obtained by the compression test for individual fruit, were dependent on several factors such as compression direction, growth conditions, and storage period, and the addition of artificial scratches. The value of compression for 'top and bottom direction' was higher than that for 'equatorial direction'. The breaking strength value of greenhouse-grown fruit with scratches was half of that without scratch. Furthermore, stored fruits with and without scratches showed significantly higher breaking strength value than that of greenhouse grown type.

　Breaking strength is determined by the mechanical characteristics of fruits and compression speed. Therefore, it is crucial to prevent the inclusion of damaged fruits in the BC and to set stacking heights based on the mechanical characteristics and transport conditions to ensure safe transportation of Satsuma mandarin using BC.

　Glutinous rice flour gel was prepared using rare sugar d-allulose (Alu). The texture property and the storage stability of gel with Alu were evaluated by texture profile analysis (TPA) and were compared with three control gels: gel with sucrose (Suc), gel with d-fructose (Fru), and gel with trehalose (Tre). TPA results showed that gel with Alu, though similar in value in cohesiveness to the three control gels, had lower values in hardness than the three control gels and lower values in adhesiveness than gels with Suc and Tre. Alu was more effective in preventing gel from hardening during storage than Suc, Fru, and Tre. The results of X-ray diffraction spectroscopy showed that Alu has higher inhibitory effect on retrogradation of gelatinized rice flour than the three sugars Suc, Fru, and Tre. The present results suggest that Alu is useful to prevent hardening during storage of glutinous rice flour gel.

　We determined the peptic starch content, amylose content, free sugar composition, and amylases activities of 20 varieties of conventional beans from Hokkaido. Multivariate analysis was conducted using the quantitative value for each ingredient. The result demonstrated that main factors, which had effects on the definite grouping and clustering into the individual varieties, included peptic starch and sucrose contents in addition to β-amylase and α-glucosidase activities.