In the first report, it was shown that the cooling effect at Japanese radish is obtained by carrying out vacuum cooling after pre-wetting process. When carrying out vacuum cooling after pre-wetting at produce like Japanese radish, in which the effect of cooling is not same between surface and inside, it is needed to grasp the internal temperature distribution in order to evaluate the cooling effect. However, it is difficult to measure temperature distribution inside a Japanese radish simply. Then, how to presume temperature change inside a Japanese radish during vacuum cooling was examined. A change in temperature on the surface of the Japanese radish can be measured comparatively easily by thermocouple. By using temperature change on this surface of a Japanese radish as boundary condition, using a heat conduction equation, the change of internal temperature of Japanese radish, especially the most difficult part to cool (; the center of the thickest part), can be grasped simply and correctly.
In the case of Japanese radish that has a big cooling unevenness, by attaining equalization of temperature distribution after vacuum cooling under low-temperature state, the effect of vacuum cooling can be increased. Therefore, it was concluded that the combination vacuum cooling and keeping under low-temperature state is effective to cooling Japanese radish. Moreover, the relation between the temperature that becomes uniform and inside temperature right after vacuum cooling was grasped.
In the result, it was proved that the way to cool with combination of vacuum cooling and operation keeping temperature cool (5°C) is effective. It became possible to estimate the temperature that is finally equalized within cooling room as well as the internal temperature of the Japanese radish during vacuum cooling. And it was found that it is possible to grasp the cooling condition of Japanese radish from vacuum cooling to the end of operation keeping cool.

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The fluorescence coenzyme F₄₂₀ was measured as an indicator of methane fermentation. The liquid portion from the methanogenic fermentor was irradiated at an excitation light of 420nm and observed by fluorescence microscopy. Changes in the fluorescence pixel rate were calculated by an image analyzer during the batch growth of acetotrophic and hydrogenotrophic methanogens. Correlation between the fluorescence pixel rate and the methane production ratio in both methanogens was high. This measurement can potentially help to characterize more metabolic status of the methanogenic bacteria.

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We measured the temperature and the relative humidity of the upper airspace of a grain silo and the atmosphere nearby the outside silo wall, to investigate the moisture movement in a rough rice storage silo of a country elevator. Using the measured values and results of model experiment, we estimated complementarily the temperature and the moisture distribution in grain layer by numerical analysis, and investigated the possibility of the dew condensation to the inside wall and the ceiling of the grain silo. As the result, we reached the conclusion that main cause for the uneven moisture distribution is the dew condensation and the water droplet from wall or ceiling into the grain layer rather than the water vapor movement through the air between the grain kernels.

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It is necessary to utilize Okara which is a byproduct of soybean processing. For this purpose, an anaerobic methane fermentation system is proposed to transform Okara to biogas which is used as recycling energy. In this experiment, a bench scale anaerobic contact process which is composed of CSTR's was experimentally used to treat the supernatant of liquefied Okara from the liquefaction reactors in the steady state. Four experimental runs with COD loading rates from 1980 to 3440mg/L/d were conducted at 30 days of HRT. It was found that the gasification process worked and showed the VS removal ratio from 72 to 80% as long as its pH was controlled within the range of neutrality. Obtained v_max and K_s as apparent kinetic parameters based on the material balance and the growth model for the process were 0.55mg-COD/mg-VSS/d and 5400mg-COD/L respectively. They indicated that the phase separation of methane fermentation activated the microbial growth and the reactors required the improvement in the mixing method. The simulation based on the energy yields in this experiment revealed that the feasibility of the anaerobic methane fermentation system to produce the recycling energy from Okara would be best improved by increasing the VA yield for the liquefaction rather than trying to improve the methane yield for the gasification.

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In order to apply magnetic force for biological wastewater treatment, method for production of magnetic immobilized cell bead was studied. In addition, magnetic bead column reactor (MBCR) with fixed bed mode was employed to investigate the process performance on denitrification process. According to the results of batch and semi-continuous operations, the appropriate magnetite (Fe₃O₄) content of the bead was 2.0% (w/v), providing high specific gravity, high permeability and low floating ratio. MBCR achieved 99.5 to 100% of nitrate removal with nitrate removal rate (NRR) of 14.49 to 43.1mg N/l/hr at low/moderate nitrate loading of 14.49 to 43.40mg N/l/hr. At high nitrate loading rates of 93.2 and 162.0mg N/l/hr, MBCR provided 80.1 and 67.8% of nitrate removals with rates of 74.8 and 110.5mg N/l/hr of NRR, respectively. Regarding the reactor design of MBCR with fixed bed mode, area nitrogen loading rate (ANLR, mg N/cm² area/hr) appeared to be an important factor. The relation between ANLR and NRR were Y=31.092ln(X)+234.8.

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In order to improve process performances of magnetic bead column reactor (MBCR) on denitrification, a turn table mode MBCR (TMBCR) was employed. Compared to a fixed bed mode MBCR (FMBCR), TMBCR had a rotating magnet turn table for the formation of a mobilized bead bed. Due to this function, TMBCR was expected to overcome the clogging problem in or on the bead bed. At 1 hour of HRT, TMBCR provided 90.69% of nitrate-N removal efficiency and 97.44mg N/l/hr of nitrogen removal rate which are 10% and 23% higher than those of FMBCR, respectively. And also, TMBCR increased the maximum applicable nitrate-N loading rate from 70 to 107.19mg N/l/hr. Additionally, scanning electrode microscope (SEM) observations of magnetic immobilized cell beads were conducted. In order to establish visible investigations of the magnetic cell beads and the immobilized microorganisms with SEM, an appropriate pretreatment method was proposed in this study.

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Countermeasures to chronic disease, occurred in many swine housings, should be carefully studied, if intended to complete the rationalized swine production systems. As one of the effective countermeasures, a segregated early weaning system has been introduced to the swine husbandry, in which the weaning age of pig is a very important factor.
In this paper, the authors discussed the appropriate weaning age of pig, measuring the periodical changes of γ-immunoglobulin content in blood plasma of 10 head of SPF sows and 19 head of pigs produced from the above sows. IgG content of nursing pigs decreased with the age increasing, and the decreasing rate of IgG content became smaller with the age increasing (P<0.01). For a seasonal effect, there was a tendency for the decreasing rate of IgG content in the season from winter to spring (P<0.08). Furthermore, the decreasing rates of IgG content with the age of pigs were highly correlated to the diurnal range of temperature (r=-0.82) and relative humidity (r=0.88) of air surrounding pigs. However, there were no relationships with the birth weight of pigs, IgG content of sows and a number of litters. Considering the immunity level of pigs, an early weaning, especially less than 14 days, should be recommended, as possible. But the effect of early weaning is little after 16 to 18 days of age, in such case it would be necessary to control the environmental temperature in swine housings in which diurnal change of temperature should be depressed.

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To verify the effects of lot management and all-in/all-out system in swine production, the authors performed 6 times feeding experiments using 1, 385 head of pigs at the large-scaled farm in which 800 head of sows were continuously raised.
By carrying out the lot management and all-in/all-out system, mortality due to chronic disease decreased to half of it in comparison with an ordinal continuous raising system, and also decreased to one fifth, if provided with sufficient ventilation air. Within the range of 16 to 25 days, dispersion of weaning age due to grouping the pig lot did not significantly affect to the feeding performances, and acclimatized feeding at furrowing pen was not necessary. However, pigs showed symptoms of some disease after 2 weeks from weaning, and then mortality became worst after 3 to 4 weeks. Therefore, it was considered that modification for raising management and pig environment was very important at the farm infested to chronic disease.

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