Ears of sweet corns are usually harvested in the early morning, but effect of harvest-time of the day on their quality has not been known for sh 2 hybrid type corns. The levels of tasty compounds of kernels were examined at three different times during the harvesting day. Sucrose, a dominant tasty component in sweet corns was highest in the afternoon (around 13:30). Dry matters were highest at the sunset time, and lowest at night, followed by the increase after sunrise. On the other hand, starch tended to increase from afternoon to the sunset time and decreased at night, although no statistical difference was detected among these data at the three points. The carbohydrate metabolism in kernels was also evaluated by measuring activities of sucrose degrading enzymes. An increase in ADP-glucose pyrophosphorylase activity responsible for starch synthesis was observed at the time of sunset. This observation was consistent with the accumulation of starch and decrease of sucrose content at the time of sunset. Moreover, a decrease in sucrose synthase activity at the time of sunrise suggested the decrease of sucrose translocation into the kernels at night. These observa tions indicated the diurnal fluctuation of carbohydrate contents. However, it was difficult to distinguish the tastes of the kernels picked at different times, because an amount of the change was only 5.6% (0.5g/100g fresh weights) of the sucrose content. Kernels contained other tasty components such as organic acids and free amino acids. Increase of malic acid and alanine at the time of sunset suggested their possible relation to the tastes of sweet corn kernels. The picking in the early morning takes no advantage for sh 2 type sweet corns on the base of contents of tasty compounds at harvest. Temperatures of kernels were changed according to diurnal fluctuation of air temperature with a time lag of 30min: the highest at 13:00 and the lowest at 30min after sunrise. The precooling period of corn ears harvested at low temp. was shorter than that of others. Therefore, picking in the early morning was suitable for preparing sh 2 type sweet corns for market distribution.

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The purpose of this work was to study the effects of sorbitol and sucrose on the content of taste-active components in meat block of walleye pollack during soaking and dehydration. The meat blocks were soaked in 0.5 M NaCl solution containing 0.5 M sorbitol and/or 0.5 M sucrose at 5°C for 24 hours. After soaking, the meat blocks were dehydrated at 20°C and 60% humidity for 6 hours. During soaking, nitrogenous compounds, free amino acids, lactic acid and so on in the blocks soaked in 0.5 M NaCl solution with 0.5 M sorbitol or 0.5 M sucrose were retained much more than those in the blocks without sorbitol or sucrose. Though the contents of those in the blocks with sucrose were higher than those in the blocks with sorbitol during soaking, no serious difference in their contents could be detected between sorbitol and sucrose during dehydration. These results suggested that sorbitol and sucrose in meat blocks controlled the flow out of taste-active components in those blocks during soaking and contributed to keeping those components in the blocks during dehydration, and also the latter was more effective than the former during soaking.

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Capsules were prepared by using the temperature sensitive polymer (polyvinylacetal diethylaminoacetate; AEA) as shell material. Salad oil as a core material was encapsulated and Sodium alginate (AN) was used by mixing with AEA in order to prevent the core material from leaking. The aqueous solution of 5°C composed of AEA and AN, in which salad oil was dispersed, was dropped into the aqueous solution of 80°C dissolving calcium chloride through the nozzle. It was investigated how the preparation conditions affected the properties of capsules. Capsules prepared were spherical and matrix type. As the concentration of AEA increased, the capsule sizes increased and the content of core material decreased. Furthermore, it was found that the increase in the concentration of AEA could repress the release of water contained in the matrix and core material. The degree of this repression was increased by coating the surface of capsules due to methylcellulose(MC).

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An apparatus which can facilely and sanitarily be installed in food processing equipment because of electrodeless detection has been developed. It comprises a radio-frequency LC resonant circuit, a solenoid coil as a detection cell and a personal computer for control and measurement on the circuit. Resonance magnitude (Ir) of the circuit, which reflects electromagnetic loss of conductive materials put into the cell, was measured by NCM and used as an index of specific conductance (k) of samples. Twelve detection cells having different configuration, dimension and resonance frequency were made. Their Ir-k curves in the resonance frequency ranging from 8.1 MHz to 44.1 MHZ were investigated by measuring NaCl solutions with various concentrations. It was found that location and magnitude of the minimum peak in Ir-k curves were influenced by resonance frequency, passage diameter, coil diameter and turns of coils. Based on this result, cell configuration for high-resolution detection of conductance had been determined, and was applied for a detector of cultivation process of Bacillus subtilis AR42 in liquid culture medium. Amount of the bacteria was monitored on the medium extracted by Ir measured with the optimized detection cell and by absorbance. From this experiment, it was shown that changes in Ir were in good agreement with those of the absorbance.

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Differences in respiration rate, C₂H₄ production, and rate of callus formation in the carrot (Daucus carota L. var. saliva DC) disks of different tissues and cutting modes were measured to determine the effect of cutting direction on the storability of partially processed carrot. The disks (diameter : 7mm, thickness: 1.5mm) were prepared as crosswise cut sections (CCS) or lengthwise cut sections (LCS) from phloem, cambium, or xylem, respectively. Both CCS and LCS of phloem and cambium showed significant increases of CO₂ production for the first 18 hr and slight decreases up to the end of storage. The CO₂ production of xylem increased through storage and the rate of increase in LCS was faster than that of CCS. Both CCS and LCS of phloem and cambium showed significant rises in C₂H₄ production and the peak was reached at 9 hr after cutting. The C2H4 production of xylem increased through storage and the rate of increase in LCS was faster than that of CCS. Total microbial count levels increased during storage for all tissue types. The total microbial counts of CCS in all tissues were lower than LCS and xylem tissue had the highest counts at 48 hr storage. The sections were cultured on MS solid media at 25°C. The rate of callus formation in the sections was cambium> phloem>xylem. The rate in CCS was greater than LCS in all tissues. The formation of callus may be associated with the production of wound healing polymers. These data support the facts that the lengthwise cut sections of carrot decayed more rapidly than the crosswise cut one, and that the deterioration in lengthwise cut one occurred first at the xylem part and subsequently at the phloem in our previous reports.

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It is known that soybean protein is not digested easily because of containing trypsin-inhibitor. When soybeans are not boiled but parched with heat, the trypsin-inhibitor is stable. Therefore, digestibility of protein of parched soybean-flour is low. This paper reports that the digestibility of soybean protein is high when soybean is parched before crushed, and it is low when parched after crushed. When whole soybeans were parched at 150°C for 20 minutes, for example, digestibility of their protein was high. However, digestibility of soybean flour protein was as low as that of soybean protein when soybeans were parched on the same condition after crushed. This suggests that trypsin-inhibitor is inactive in raw whole soybeans, but is active when they are crushed.

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To determine the effects of high and low viscous sodium alginates (HAG and AG5 respectively) at 2% level on the cecal microflora and levels of serum lipids, these diets were administered to male rats for a week. No significant effects were shown in the case of HAG diet, while cecal pH value, serum triglyceride, and serum cholesterol clearly dropped in the case of AG5 diet. Furthermore, the ratio of bifidobacteria to total viable counts of cecal microflora showed an increasing trend by the intake of AG5. These results indicate that the diets containing high and low viscous sodium alginates have different effects on the intestinal microflora and the levels of serum lipids.

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Effects of different fertilizers on sugar and mineral contents in melon fruits were studied. The melon fruit grown on oil cake as a main N-source contained higher soluble solids, sucrose, glucose and fructose, and lower citric acid than that grown on ammonium sulfate as a N-source. The calcium content was higher in melon fruit grown on oil cake as comparing with ammonium sulfate.

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Using a general membrane emulsification apparatus as circulating or stirring a continuous phase, we prepared W/O emulsions from food ingredients using hydrophobic microporous glass membranes. But by these apparatuses, W/O emulsions especially prepared from food ingredients, such as oils and fats with high viscosity, were easily crushed by a mechanical shear stress of pumps and rotors while the preparation of W/O emulsions required a long time. So a high-concentrated monodispersed emulsion could not have been prepared. Then we investigated the membrane emulsification apparatus to prepare high-concentrated monodispersed emulsions. We improved the system stirring the continuous phase by revolving the emulsification vessel itself, to prevent the dispersed droplets from the mechanical shear stress. As the result, it was possible to prepare monodispersed emulsions by revolving the emulsification vessel at 250-550 min-1 The greater the revolutions were, the smaller the average dispersed droplet diameter was. Then we could prepare high-concentrated monodispersed W/O emulsions using this improved apparatus.

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We prepared W/O emulsions from food ingredients using the hydrophilic microporous glass membranes immersed with oils and fats or an oil phase. We investigated methods and conditions for preparation of a monodispersed emulsion by this technology. As the result, a monodispersed emulsion could be prepared by selecting appropriate operating conditions, such as the concentration of emulsifiers and the revolutions per minute of the emulsification vessel. The average dispersed droplet diameter of the emulsions was proportional to the average pore diameter of the membrane. And the plotted straight line had a slope of nine, under using corn oil for continuous phase and the revolutions per minute of the emulsification vessel at 400 min-1 But the greater the revolutions were the smaller the average dispersed droplet diameter was. By a membrane emulsification system, the flux of the dispersed phase was too low in case of using a general hydrophobic membrane. So, it had been difficult to make this system practical for large-scale application. But using the hydrophilic microporous glass membranes immersed with the oil phase, it was possible to increase the flux of the dispersed phase or the preparation rate of monodispersed emulsions to about 20 times.

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There have been few reports concerning to discuss about the differences of components of lemon oils prepared by the same method in different countries and differences of them prepared by different methods. We discussed on the differences between lemon oils of California and Sicily prepared by Inline method and their differences among lemon oils of Sicily prepared by three conventional methods, In-line, Sfumatrice and Pelatrice-methods. GC and GC-MS analysis showed some differences between California lemon oil and Sicily lemon oil prepared by In-line method. That is, the amounts of n-nonanal, citronellal, α-terpineol, neryl acetate and geranyl acetate in Sicily oil were larger than that in California oil. Small differences were observed among Sicily oils prepared by In-line, Sfumatrice and Pelatrice-methods. However, when the fresh oil prepared by Pelatrice-method was contacted with lemon juice for 0.5, 1, 2, 3 and 5 hours, the citronellal and linalool in the oil were reduced according to contacting period. This tendency coincided with the tendency of reduction of fresh perception of the oil. The fresh perception reduction was recovered with the addition of linalool.

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