The use of rack type grain drying facility with a simple operation mode is increasing in recent years and the paddy is processed by individuals. This kind of facility is convenient for establishing a traceability system for grain production. However, as the deep bed drying is performed in this facility, serious uneven drying may occur. It is therefore necessary to consider the proper conditions for aeration and operation in order to prevent quality deterioration. We developed a simulation program to analyze the effect of the various conditions on the grain's drying process. In the simulation, the average value as well as the distribution of moisture content could be obtained. This program will be used to obtain the proper conditions for different types of grains, such as paddy, brown rice, wheat, soybean and so on.

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The genetic relationship among 15 lettuce cultivars (Lactuca sativa L.) was examined by RAPD analysis using 12 dodecamer primers singly or combining two primers in a single PCR. The cultivars examined were classified into three groups based on the numerous polymorphisms of DNA fingerprints. The main group consisted of thirteen cultivars with crisphead lettuces having compact leaves form tight head (6 cultivars), such as 'TE242', 'Shizuka', 'Shisuko', 'King Shisuko', 'Sodegaura', 'V lettuce', a cultivar looseleaf lettuces with a bunch of green or red leaves (5 cultivars), such as 'Redfalder', 'Banchu Redfire', 'Chimanchu', 'Dancing', 'Red Wave', cultivar cos lettuces having long upright leaves (1 cultivar), such as 'Romaine lettuce' and stem lettuces like big asparagus shape with thin leaves (1 cultivar), such as 'Stem lettuce'. The second group included 1 cultivar of cos lettuce such as 'Cos lettuce' and the third group included a stem lettuce cultivar, 'Cairn'. The largest genetic distance was the relation with 'Cos lettuce' and 'Cairn', while the smallest genetic distance was found among the crisphead lettuces, such as 'TE242', 'Shizuka' and 'Shisuko', and looseleaf lettuces, such as 'Redfalder', and 'Banchu Redfire'.

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Effects of air-blowing treatment on the yield, characteristics of leaf stomata, transpiration and vase life of the cut stems were investigated in rose (Rosa 'Asami Red') plant. The yield of cut flowers was increased by air-blowing treatment, especially in winter when humidity in a greenhouse was high. Cut roses obtained from the plants given air-blowing treatment had a reduced stomatal size compared to the control group. The cut roses in the air-blowing treatment group showed a lower transpiration rate after harvest than those in the control group. The air-blowing treatment resulted in delayed bent neck symptom and longer vase life of cut stems. Air-blowing may be considered to enhance CO_2 absorption and transpiration in a greenhouse by thinning leaf boundary layer and bringing functional stomata. It is concluded that air-blowing treatment is an effective method to increase yield and to prolong the vase life of cut roses.

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The purpose of this paper was to clarify the effects of prostrate and erect canopies on the soil temperatures and the deviations of 10 soil temperatures beneath film mulch in a field and inside a glasshouse. Six experimental plots were prepared inside and outside the house. These plots had either no mulch, or black mulch, and had either prostrate canopy, erect canopy, or no canopy. The deviations of soil temperature were larger inside the glasshouse than in the field. Further the deviations among canopy types and the time of day were very small in the house, as compared with those in the field. In order to determine the high-low relationships of the soil temperatures between two plots, threshold values of soil temperatures were adjusted. Comparison of the threshold in the field and inside the glasshouse showed that a higher threshold was required inside the glasshouse than in the field to determine the high-low relationships. The effect of the presence or absence of a canopy on the threshold in the glasshouse was less than that in the field.

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Moisture conditioning is one of the most important unit operations in rice processing plant because the quality of polished rice depends mainly on this treatment. The moisture adsorption properties for polished rice depend on the surrounding air conditions and its internal structure. In this study, we investigated the effects of moist air temperature, humidity and moisture content of polished rice on equilibrium moisture content and adsorption rate coefficient. As for equilibrium moisture content, the empirical equation was derived and the significance of parameters was tested statistically. The semi-theoretical equation for prediction of adsorption rate coefficient was also derived as a function of moist air temperature, humidity and moisture content of polished rice. These equations will be useful for design of moisture adsorption system for polished rice.

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Microwave cooking of sweet potato involves temperature, moisture content and volume changes that strongly coupled. A microwave heating simulation model considering heat and mass transport coupled with large volume change due to moisture loss was developed and solved numerically. Results from modeling agreed with the experimental results in starch gelatinization process as observed by a scanning electron microscope (SEM). Moisture content measurement also carried out to verify the model at microwave radiation power of 400W and 600W. The model was applied to optimize intermittent on-off heating of diced sweet potato with fixed microwave radiation power of 125W. The result of this simulation showed that the intermittent on-off heating could lead to more uniform temperature distribution within the sample while constraining the maximum surface temperature of 65℃ to prevent inactivation of - amylase that helped producing sugars. The development of this study is useful to improve the quality of cooked sweet potato.

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Freezing operation has been established as excellent method of preserving high quality in foods. The quality of frozen food is closely related to freezing and thawing processes because damage to the product is mainly associated with rate of ice formation, which is related to rate of heat removal. We developed and validated a freezing model based on the thermal diffusion equation with phase change of water in green pea. The model was solved numerically by using the orthogonal collocation method and was verified experimentally with the data collected using a fluidized bed freezer. We also investigated the estimation of freezing ratio simply as a function of temperature. The estimated result agreed well with the data in literature. Attained results in this article may contribute to the understanding and improvement of the freezing process of foods.

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