To simplify and quicken the process for refing Konnyaku-powder and to deodorize the refined crude Konnyaku-powder, it was attempted to partly improve the alcohol precipitation method for refining Konnyaku-powder by introducing a step of ultrasonication. Effects of this treatment on the physical properties and the taste of the Konnyaku-powder were studied, and the following results were obtained. (1) The Konnyaku-powder refined by this method involving a step of ultrasonication was much superior in the qualities to a control prepared by the method without ultrasonication step. (2) When refined under appropriate conditions (temperature of extracting water: 40°C, ultrasonication time: 15 minutes), the Konnyaku-powder was obtained in a 90% yield. Compared with the control, this product had a higher whiteness and provided a gel with considerably reduced odor characteristic and a so1 with somewhat higher apparent viscosity. Also, its taste was highly evaluated. Namely it is considered that the refinement method involving a step of ultrasonication can be easily performed, compared with the existing method, and is useful in the improvement of the qualities of Konnyaku-powder.

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MRA (multiple regression analysis), NN (neural network) and FNN (fuzzy neural network) were applied in order to construct the models estimated from the analysis data for the sensory evaluations of various coffee samples. The estimated values using the MRA model for several sensory evaluations did not coincide well with the real values. NN and FNN models had high precision for sensory evaluations except for the sensory evaluation of "Hard". Membership functions and production rules, which were understandable qualitatively, were obtained from the constructed FNN model.

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Near infrared transmittance spectra of normal and aged soybean seeds were measured using a specially designed sample cell for a single seed and were analysed by Principal Component Analysis (PCA) and Discriminant Analysis (DA) using PC scores for the classification of normal seeds and aged seeds. Soybean seeds were acceleratedly aged under an ambient condition of 42°C and 98% RH for 3, 5 or 7 days. As control some other seeds were also stored under condition of 15°C and 98% RH for 7 days, preserving the ability to germinate. After these treatments the seeds were dried at room temperature till they become initial water content. In multiplicative scatter corrected (MSC) spectra between normal and aged seeds somewhat changes were observed. The log (1/T) at 990 nm decreased with the increment of ageing days, while the log (1/T) at 1010 nm increased to the contrary. Aged seeds (7 days) were clearly separated from control using on the plane with the axes of second (PC2) and third (PC3) principal components, derived from PCA of MSC spectra. The results of DA using 2PC scores (PC2 and PC3) which were effective to separate aged seeds, showed that 60% of aged seeds for 3 days, 80% of aged seeds for 5 days and 100% of aged seeds for 7 days were correctly classified. Phospholipids content in soybean seeds decreased with ageing, and then became half after 7 days, while total lipids content was constant. The loading plot for PC3 were similar to the spectrum of lipids, suggesting that PC3 reflected the changes of phospholipids during ageing. Consequently, it was concluded that NIR spectroscopy had a possibility for classifying normal and aged soybean seeds, and that the change of phospholipids content was an important factor for this classification.

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Cooperative studies on the measuring condition of pasting properties of milled rice flours were carried out using new system, "Rapid Visco Analyser" (RVA) and the same 6 rice sample flours among 7 research institutes. Those rice cultivars were Tankei No-2019, Tankei No-1915, Tankei No-2018, Tankei No-2024, Nipponbare and Hoshiyutaka, of which amylose content was 6, 10, 12, 14, 20 and 25%, respectively. The measuring conditions were as follows ; 1 min of 50°C, 4 min for heating from 50°C to 93°C, maintenance for 7 min at 93°C, 4 min for cooling from 93°C to 50°C, and 3 min at 50°C. Peak viscosity and breakdown were shown to be highest for rices, of which amylose contents were 12-14%, although the higher amylose rices revealed the higher final viscosity and consistency. It was clarified that the repeating errors (2-9% CV for 3 CR and 1-4% CV for 3 D) and the instrumental errors (3-49% CV for 3 CR and 1-5% CV for 3 D) were small in case of RVA tests using the same type instruments.

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From a point of view to develop a system including a compression test for evaluation of Kamaboko gel properties, the concerned equipments and their combination and conditions for the measurement were investigated, and following results were obtained. (1) The steps from measurement to presentation of the result (operation of compression test, calculation of mechanical parameters, arrangement of the data, factor analysis, three-dimensional presentation ; texture mapping analysis) that have been operated separately were combined to construct a system consisting of a personal computer including programs for all procedures, compression tester of easier and time-saving testing, and printer for data output. (2) The influences of testing conditions on physical properties involved in texture mapping analysis were examined. The combinations of sample thickness and plunger speed, 3mm and 4.8mm/min and 4mm and 7.2mm/min, were found to be appropriate for the testing conditions. These conditions seem to be easier and practical compared to the previous condition of 2mm and 1.2mm/min, therefore, the present system is expected to be improved as to usefulness.

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To understand lipid degradation in buckwheat in more detail, the lipolytic enzyme activity of an extract from buckwheat was measured by a flu-orescent method using 4-methylumbelliferone. The lipolytic enzyme activity of buckwheat was 880 pmol/min/mg on the average, which was 5-7 times as higher as that of wheat flour. The water activity above 0.28 did not depress the lipolytic enzyme activity during 1 month stor-age at 25°C. Heating treatment (120°C, 7 sec) of buckwheat was effective to inhibit the lipolytic enzyme activity and increase in free fatty acid. These suggest that the accumulation of free fatty acid in buckwheat during storage are mainly caused by lipase.

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Lethal effects of contact glow discharge electrolysis (GDE) on suspensions of various bacterial cells and spores were investigated. Microbial cells were suspended in 100 ml of D.008% NaC1, and the suspension was subjected to GDE. GDE was carried out at 30±2°C with saturation by argon gas and with constant stirring using a glass vessel equipped with platinum wire as an anode and coil as the cathode. Viable cell counts of vegetative cell types were reduced by GDE treatment by up to more than six orders of magnitude. Death rate constants of various microorganisms were determined from survival curves. On the other hand, endospores and conidia were more resistant to GDE than vegetative cells, no matter how high a density field of GDE was applied.

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