Relationship between producing conditions and product qualities of "Quick Cooking Rice" were investigated. It is possible to eliminate the steps of washing, soaking and steaming after cook using "Quick Cooking Rice". The product contained high amount of moisture contents (about 35%), showed high whiteness and revealed preferable texture by cooking immediately after the addition of water and expanded well during the cooking. It was clarified that the gelatinization parameters, such as peak viscosity and final viscosity, measured by a Rapid-Visco-Analyzer could be used as suitable indices for the eating qualities of the products. As results of sensory evaluation of palatability and textural properties tests, the product of low-gelatinization degree (about 80%) was the best, the product of strong washing was the better and the product of pasteurized was evaluated as the worst.

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Unsteady state behavior of moisture transfer during a poultice up process which has been applied to uniform distribution of moisture content in the course of forced ventilation drying of foods was characterized by using a fish paste sausage. For the quantitative analysis of moisture transfer, effective diffusivity (D_e) and activation energy of moisture diffusivity (E₀) were evaluated. The characteristic behavior of D_e obtained was classified into two regions depending on the value of moisture content (W₀) in the sausage : Region I (W₀>100%-d.b.) in which D_e at 50°C was decreased from 2.7×10^-6 to 1.6×10^-6m²/h with decreasing W₀ and region II (W₀<100%-d.b.) in which D_e gave 1.6 ×10^-6 (±0.2)m²/h without depending on W₀. E₀'s at regions I and II were evaluated as 16.5 (±1.0) and 9.6 (±0.6)kJ/mol, respectively. Based on the results obtained, it was considered that the mechanism of moisture transfer and the physicochemical structure of water distributed in the sausage should differently be characterized between regions I and II.

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In order to analyze the kinetic staling rate of bread made by no-time frozen dough method, the three methods were applied to determine the staling rate of bread firmness and the retrogradation rate of starch in bread. The results were summarized as follows: (1) The staling rate (staling rate constant) of bread made from frozen dough was almost similar to that of bread made from unfrozen dough. Furthermore, the freezing of dough hardly influenced the retrogradation rate of starch in bread. (2) The increase of staling (the changes of crumb firmness) in bread made from dough frozen for a long period was due mostly to a decrease of loaf volume and a degradation of fine crumb structure, which was supposed to be caused by freezing damages of yeast and dough structure.

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As for oily waste water treatment in food industries, the membrane technology has a large potential to reduce the operation time, equipment space and total costs. Using crude lecithin/water emulsion as a model of oily waste water, filtration characteristics on the flux and total organic carbon (TOC) rejection were investigated with a wide range of membranes in reverse osmosis, nanofiltration, ultrafiltration, and microfiltration. Constant flux and TOC rejection were obtained in crossflow filtration with hydrophilic membranes having smaller pores than the emulsion droplets (1-2μm). Free phospholipids were removed with reverse osmosis membranes or nanofiltration membranes having high NaCI rejection abilities. When microfiltration membranes having larger pores than the emulsion droplets were used, the membrane characteristics such as the pore structure and hydrophobicity largely affected the filtration characteristics: asymmetric membranes gave relatively high fluxes when its loose side was used against the feed emulsion as a depth filter, symmetric membranes having a spongoid pore structure and a pore size similar to the emulsion droplets brought about almost 0 flux owing to an extreme progress of pore blocking, hydrophobic membranes of adequate pore sizes showed a possibility to result in the negative TOC rejection.

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Antifungal activity of TBZ (2-(4' -Thiazolyl)-benzimidazole) against Aspergillus niger was evaluated by a conduction-type batch calorimeter. The thermograms associated with the growth of A. niger were shifted toward a longer incubation period as the TBZ content in the medium increased. The growth rate and the minimum inhibitory concentration were calculated by the use of the inhibition kinetic model proposed by TAKAHASHI et al. A drug potency (antifungal efficacy) curve of TBZ was drawn based on the kinetic parameters obtained. Therefore, the calorimetric method was considered to be useful for quantitative evaluation of the efficacy of antifungal agents.

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For liquid dairy products of O/W emulsions with high protein contents, it was noteworthy that the droplet size of emulsions changed variously under the normal homogenizing operation condition in an emulsification process and droplet coagulation was caused by homogenization and sterilization systems. And we studied the dispersed condition of the O/W emulsions. The more the repeating pass of homogenization was at a constant pressure in the emulsification process, the smaller the droplet size was with narrow distribution. But during these operations, the phenomenon of droplet coagulation was appeared evidently. To evaluate the droplets coagulation, we presented an equation (coagulation parameter B)consisted of the average droplet diameter, the droplet diameter deviation and the rate of droplet diameter below 0.5um. As a result, the condition of the emulsion was expressed properly by coagulation parameter B. The correlation between the droplet diameter size before heating and after heating was found evidently in the heating process, and the droplet diameter after heating was slightly larger than that before heating. And the correlation between emulsion viscosity and the average droplet diameter or coagulation coefficient B was observed evidently. These results clearly indicated that the droplet coagulation was enhanced in these experimental compositions by heating process.

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In order to study the relationship between cohesion and void volume of cooked rice, two-dimensional assembly of 350 cylinders was set up in the condition of the closest packing within 10×10 cm frame with a constant lateral force. The size of cylinders was 0.5 cm in radius and 5 cm in length. Three kinds of materials for cylinders, polyethylene (PE), silicon rubber (SR) and foamed rubber (FR) were examined. Normal force-deformation curve and the fractional void ratio betweencylinders were determined. PE assembly showed clear V-shaped faulting crack. With the increase in void volume by adding polypropylene straws (PPS), it seems that compressive force was absorbed by voids of PPS and breaking strain was twice as much as that of PE alone. On the other hand, SR assembly showed no clear crack. SR+PPS assembly behaved as if the force-deformation curve of PE+PPS was expanded. FR assembly was compressed mainly into the central part and void parts appeared in both sides. As compressive strength parameters, the angle of internal friction (φ) and apparent cohesion (c), were calculated by the analysis of Mohr-Coulomb curves in various lateral force data. Increasing with void between the assembly, any of these materials decreased in its friction. It was considered that the above mentioned behavior is well reflected in actual cooked rice.

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Simple and rapid extraction methods for DNA extraction from single milled rice grains were investigated for cultivar identification of domestic rices by RAPD analysis. Single grain of milled rice was treated with ISOPLANT kit (Nippon Gene) or FastDNA kit H (BIO 101), and extracted DNA solutions were used for PCR amplification. These extraction methods were applied for RAPD analysis to identify 10 dominant cultivars in Japan. RAPD data using DNA extracts from one grain of milled rice were useful for the cultivar identification of rice when the suitable primers were used in RAPD analysis. It became possible that 10 dominant rice cultivars in Japan were identified by RAPD analysis from one grain of milled rice using 5 primers and 6 discrimination bands.

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It has been known that the seed of "Moroheiya"(Corchorus olitorius L.) contains cardiac glycosides such as Strophanthidin (SP) as an aglycon. Using trimethylsilyl (TMS) derivatization and GC/MS analysis, a simultaneous method for the determination of SP and Digitoxigenin (DG) in "Moroheiya" was developed. The condition for TMS derivatization of SP and DG was examined using commercially available standard reagents. Each reagent was treated with a mixture of pyridine, N, O-bis (trimethylsilyl)-acetamide, trimethylsilylimidazole and trimethylchlorosilane and analyzed by GC/MS. Their mass spectra demonstrated the formation of the completely and partially derivatized TMS ethers, SP (TMS)₄, SP (TMS)₃, SP (TMS)₂, DG (TMS)₃ and DG (TMS)₂. The complete derivatization from SP to SP (TMS)₄ and DG to DG (TMS)₃ required the reaction for about 20h at 100°C. SP and DG in C. olitorius seeds and processed "Moroheiya" foods were prepared as follows; "Moroheiya" sample was hydrolyzed in a 1% sulfuric acid-methanol (1:1, v/v), and then the resulting hydrolyzate was extracted with dichloromethane. The extract was dried up and derivatized for 20h at 100°C. The resulting derivatives, SP (TMS)₄ and DG (TMS)₃ were determined by GC/SIM (selected ion monitoring). The mass spectra of those derivatives were not significantly affected by interfering components. Thus, this method is confirmed to be very useful for qualitative and quantitative analysis of SP and DG in "Moroheiya" samples. The detection limits of SP and DG were 5mg/kg and 1mg/kg, respectively. By the present method, 5.9-6.2g/kg of SP and 0.15-0.24g/kg of DG were detected in C. olitorius seeds, while neither SP nor DG was detected in processed "Moroheiya" foods.

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Precooked rice dishes, box lunch and "Onigiri", cooked rice ball have been increasing in the market these days. As it is obligated that the cultivar of the material rice grains of these products should be displayed without mislabeling, the development of the objective detection method is indispensable. Therefore, RAPD method to identify the cultivars of the cooked rice grains were investigated. Milled rice grains were cooked in the plastic microtubes, followed by the enzymatic digestions using α-amylase for starch and proteinase-K for proteins. DNAs were extracted by phenol solution and purified by ethylalcohol. The DNAs were proliferated by the PCR method with the existence of various kind of primers (10 mers and 12 mers). The resultant electrophoregram showed that the dominant 10 Japanese rice cultivars could be identified by the combination of 6 selected primers and suitable DNA bands. It became possible to identify the rice cultivar using a single grain of cooked rice by the enzymatic digestion of starch and proteins followed by the application of RAPD method.

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Recently, application of high pressure to food has been utilized not only for sterilization but also for the development of new materials and the improvement of food quality. But foods are different from one another in the time and the effect of high pressure treatment. In the preceding paper, we found that the high pressure treatment suppressed heat deterioration of fractionated milk fat. The purpose of this study is to show that long time pressurization can suppress the heat deterioration of hard milk fat which is used as a raw ingredient in confectionery and bread baked at high temperatures. The following results were obtained: (1) All experiments indicated that deterioration of hard milk fat proceeded with an increase in heating time. (2) It was revealed from measurements of weight change rate, electric conductivity and induction time of oxidation that the high pressure treatment for 4 h to the hard milk fat repressed the heat deterioration than non-pressure or high pressure treatment for 1 hour.

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Stems and leaves of tea shoots were separately incubated under anaerobic condition and their amino acid levels were analyzed. γ-Aminobutyric acid (GABA), which was produced from glutamic acid by glutamate decarboxylase, was more in the stems than in the leaves. Crude Gabaron tea, which was made of anaerobic incubated shoots, was also separated into leaves and stems. The contents of amino acids in each part were measured. Stems contained higher GABA than leaves as expected. From these results, tea stem is very important to ingest GABA.

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