The objective of this study was to develop an energy-saving ventilation system for a Shiitake cultivation facility. While in the cultivation stage, the spawns generate heat and CO₂ during their growth. To maintain an optimal growth temperature and labor-safe CO₂ concentration, an air conditioner and ventilation must employed. For energy saving, a heat exchange ventilator is widely used. For a more efficient utilization of this ventilator, we focused on two modes: heat exchange and normal ventilation. When the room temperature is higher than the outside temperature, using cool air with normal ventilation benefits the air conditioner. Moreover, we propose that spawn heat may be used as a heat source with heat exchange ventilation, when the room temperature is low. To determine the ventilation mode, we designed a control unit considering the inside and outside temperatures of a cultivation facility. After operating this system for one year, the highest efficien cy was observed at an outside average temperature of 10 to 15℃. Therefore, a 25 % energy saving was achieved in this cultivation facility in Tamano city, Okayama.

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Rice bread has a low volume and hard texture compared with wheat bread because rice flour contains no gluten. We aimed to investigate whether partially replacing non-glutinous rice flour with extruded gelatinized rice flour could improve the textural characteristics of the batter and baked bread. In rice bread containing glutinous rice flour, partial substitution with gelatinized rice flour improved the Young’s modulus and bread volume. A substitution level of 15% gelatinized rice flour provided batter with the largest bubble and film thickness and rice bread with the most pleasant texture. In contrast, in rice bread containing rice gruel partially replaced with gelatinized rice flour, the volume and Young’s modulus were not affected so any improvements in the physical properties would not be expected. Changes in the dynamic viscoelasticity (G′ and G′′) of the batter containing glutinous rice flour and rice gruel corresponded with changes in sensory evaluation scores and the valu es of Young’s modulus in the baked bread. The partial replacement of non-glutinous rice flour with gelatinized rice flour has been shown to change the characteristics of rice batter, and consequently, the physical properties and texture of the baked rice bread.

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To develop a rapid method for miso quality assessment, the availability of visible/near infrared spectroscopy was evaluated. Visible/near infrared reflectance spectra of miso samples were measured, and the relationship between the sensory evaluation scores and visible/near infrared spectra was examined by partial least squares regression analysis. As results, there was a close relationship between the sensory evaluation scores and visible/near infrared spectra, and visible/near infrared spectroscopy could be used to assess the quality of miso.

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Mackerels are generally preserved using salt, and salt is known to preserve the taste component of fish. Bittern is a liquid with a salinity ; therefore, it is expected to exert similar protective effects on fish taste component. The main taste component in fish is inosinic acid (IMP), and suppression of IMP-degrading enzyme activity is necessary to preserve this component. In this study, we compared the effects of salt and bittern on the activity of IMP-degrading enzymes in chub mackerel. At 5 % NaCl, the main component of salt, the activity of IMP-degrading enzymes decreased to 80 % that observed in the absence of salt treatment. At 2 % MgCl₂, the main component of bittern, the activity of IMP-degrading enzymes decreased to 70 % that observed in the absence of salt treatment. These results suggest that bittern can preserve the taste component in fish.

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