"An", which is a Japanese traditional cake base, is made from adzuki beans and other legumes (mainly Phaseolus vulgaris) by cooking, grinding, removing hulls and washing. It is a mass of cells separated from cooked legumes. "An" was prepared from seven varieties of legumes, i.e. P. vulgaris (Otebo, Fukushirokintoki, Ofuku and U.S. Great-northern), P. coccineus (Oshirohana), P. lunatus (U.S. Baby-lima) and Vigna angularis (Erimo-shozu) to examine the variant differences in yield, chemical composition, sensory evaluation and physical properties. There were not so distinct differences in yield (wet and dry basis) and chemical composition of the "An" among the varieties. However, the moisture content of "An" prepared from Oshirohana was fairly high (66%) than those of the other varieties (60-63%). It seems to be due to pectin, because the pectin content of the "An" from Oshirohana was higher than those of the other "An". Sensory evaluation, i.e. dispersibility and stickiness in mouth was different depending on the varieties. Erimo shozu and Otebo were softer and more dispersible in mouth compared with the others. These differences corresponded to the changes of hardness, cohesiveness and adhesion force during repeated biting by a physical measurement apparatus (Tensipresser).

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The properties and compositions of the "An" prepared from Oshirohana and Otebo under different cooking periods (60, 90 and 120min) at 100°C and different temperatures (100, 110 and 120°C) for 60min were comparatively studied. The "An" of Oshirohana showed always higher moisture and pectin contents. By treatment of pectinase, both moisture and pectin contents of the "An" from Oshirohana decreased, suggesting a significant relationship between them.
The sweetened "An" of Otebo prepared at 100°C was pasty with cohesiveness, whereas that of Oshirohana was not pasty without cohesiveness. This is assumed due to the higher pectin content of the latter. Sweetened "An" of Oshirohana, which was preliminarily treated with pectinase, was pasty with cohesiveness.
The "An" of Otebo cooked at 110 and 1200°C was higher in moisture but lower in pectin contents, therefore substances other than pectin may account for the higher moisture content.

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"An" (bean jam) prepared from 6 varieties of Phaseolus group (4 P.vulgaris, 1 P. lunatus, 1 P. coccineus) and l Vigna variety (Vigna angularis) were observed under a light microscope and a scanning electron microscope. "An" particle of Oshirohana (P. coccineus) was the largest ellipsoid. Other "An" particles were all globular except Fukushirokintoki (P. vulgaris). There were differences in thickness of outer layer (cell wall-like layer corresponded to cell wall of live cel1) of "An" particls; Oshirohana and Otebo (P. vulgaris) thicker and Erimo-shozu (V. angularis) thinner. Many wrinkles, deformed cell wall-like layer caused during sample preparation for scanning electron microscopic analysis were observed on the surface of particles, and they were deeper in Oshirohana and shallower in Erimo-shozu, corresponding with thickness of cell wall-like layer observed under the light microscope. In order to elucidate the surface structure of "An" particles, they were treated with enzymes. Although proteolytic enzyme followed by cellulase did not remove the outer layer of "An" particles, alkaline solution or macerating enzyme followed by cellulase effectively exfoliated the layer. Starch granules were separated from "An" particles by treating with alkaline solution followed by cellulase to removetheir outer layer and leaching in alkaline solution again to remove remaining protein in "An" particles. The separated starch granules were found to be gelatinized because of disappearance of maltese cross by polarized micrograph.

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Oligopeptides which inhibit angiotensin I converting enzyme (ACE) were studied by industrial methods and isolated from the hydrolyzate of sardine muscle with Denazyme AP. The preparation involved QAE-Sephadex A-25, SP-Sephadex C-25 and Bio-Gel P-2 followed by high performance liquid chromatography. Five dipeptides were identified. The amino acid sequences of these dipeptides analyzed by the Edman procedure were Tyr-Pro, Val-Phe, Ile-Phe, Trp-Ile and Trp-Leu. The IC₅₀ values of these dipeptides for ACE from rabbit lung were 2440, 250, 100, 82, and 51μM, respectively. The corresponding synthetic peptides were found to be identical with the isolated inhibitors in the ACE inhibitory activities.

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Supercritical carbon dioxide (SC-CO₂) extraction of limonoids and limonoid glucosides (LGs) from defatted Natsudaidai seed meals was examined under various conditions. The total amount limonoids extracted by SC-CO₂ was less than those extracted by organic solvent. Very little amount of limonin, deacetylnomilin and LGs were extracted by SC-CO₂. The results obtained with SC-CO₂ extraction with modification of entrainers indicated that acetone was the best entrainers among tested for extracting limonoids. However 70% ethanol was more efficient for LGs. Extraction pressure and the amount of CO₂ were important factors in this experiment. The extraction yield of limonids depended upon pressure, but were not affected by temperature. The yield increased with increasing pressure and sharp increase in nomilin extraction was observed between 250kg/cm² and 300kg/cm². The extraction of deacetylnomilin, nomilin and obacunone was sharply increaed till the 50 g-CO₂/g-seed level and remained relatively constant thereafter. The yield of limonin gradually increased with increasing amount of CO₂. The optimal extraction ratios of deacetylnomilin, limonin, nomilin and obacunone were 13.9%, 19.1%, 82.1% and 38.9%, respectively. On the other hand, a higher yield (81.0%-99.4%) of LGs was obtained, except for limonin glucoside.

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Changes in respiration, ethylene production, 1-aminocyclopropane-l-carboxylic acid (ACC) content and ACC synthase activity of shredded cabbage stored at 10°C were examined. The effect of allylisothiocyanate (AITC) on them was also investigated. Respiration rate of the control shredded cabbage was increased rapidly, while the respiration of samples treated with AITC more than 2.5mg per 100g cabbage were suppressed. Ethylene production, ACC content and ACC synthase activity of the control were increased markedly during storage, while AITC inhibited their increase similarly. The treatment with 5.0mg AITC per 100g cabbage immediately after cutting suppressed the increase in ethylene production and ACC synthase activity of shredded cabbage for 72h almost perfectly. However, when the sample was treated with AITC of the same concentration after 72h to show high rate of ethylene production, the ethylene production and ACC synthase activivity of which remained at 58 and 32% of the control. The results indicate that AITC has not only direct, but also indirect inhibitory effects on ethylene production, which results in strong suppression of ethylene synthesis in shredded cabbage.

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The mechanism of heat transfer in a sterilizing process of canned foods by vacuum pack was investigated using a model can to establish the optimum operating condition. The relations between the heat transfer rate in this can and the vacuum degree or the volume of water for steam which became a heating medium for foods were experimentally investigated and an empirical equation was obtained. Furthermore, the heat transfer coefficients for steam condensation on the surface of solid food in this can were calculated numerically by fundamental equations and a relational equation was obtained.

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Chemical compositions and putrescible potential of four commercial shottsuru (Japanese fish sauce) samples produced by different manufacturers were examined. The compositions of fresh samples were as follows; PH 4.54-5.56, NaCl 26.2-30.4%, total nitrogen 301-1598mg/100ml, volatile basic nitrogen 36.2-170mg/100ml, trimethylamine 16.2-44.2mg-N/100ml, glutamic acid 378-1081mg/100ml, acetic acid 33.2-179mg/100ml, inosinic acid 4.5-9.7mg/100ml, tyramine 0.18-13.1mg/100ml, histamine 0.20-16.6mg/100ml, and viable bacterial count less than 10-5.9×10⁵/ml. After storage at 30°C for one month, only one sample whose PH was highest among the samples was putrefied. In contrast, bacteria were not detected after the storage in the other two samples which contained high levels of levulinic acid and showed low pHs of 4.54 and 5.02.

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Buckwheat flour treated with a twin screw extruder (EX-BW flour) was found to have a strong self dough-binding property with water. The EX-BW flours processed at the maximum extruding pressure obtained at around 130°C were very preferable to dried buckwheat noodle processing when formulated with an appropriate amount of common buckwheat flour. The optimum water absorption of the EX-BW flour was 11/2 times larger than that of common BW flour. Its dough showed a characteristic rubber-like elastic properties. A mechanical noodle processing with a simple formulation of the EX-BW flour and common BW flour at the ratio of (4:6) to (5:5) and 35% added water to the total flours was successfully carried out to prepare fine dried buckwheat noodles, a type of new genuine product, in a continuous 200kg flour processing scale. The optimum cooking time of the dried buckwheat noodles in ten times amount of boiling water was 5min. The organoleptical qualities in taste and texture were investigated.

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Breaking stress has been taken as "hardness" to describe mechanical properties of tofu (soybean curd). However, "hardness" is defined as a textural property indicating the resistance to deformation by applied force. Unfortunately, a number of reports on mechanical properties of tofu have given insufficient information to compare each other's data. We have carried out puncture and compression tests of tofu and monitored the gelation process of soymilk by a dynamic viscoelastic measurement. Apparent breaking stress in the puncture test depended on plunger diameter, but in the compression test it was independent of sample diameter. The following suggestions are given in destructive tests of tofu.
1) A result should include breaking stress and breaking strain data, since breaking force (load) depends on the size of the plunger and the sample gel.
2) Shape and size of the plunger and the samples and test temperature should be shown, because they affect the breaking properties of tofu.
3) Since a fairly long time is required to form a complete gel structure of tofu, a test should use samples which are aged sufficiently after coagulant addition.

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A method for determination of nitrate, sulfate and oxalate ions in vegetables and their products has been developed. Their anions were detected by electrical conductivity detector. TSK gel IC-Anion PW and 30mM boric acid-1.3mM gluconic acid-1.3mM sodium tetraborate-10% acetonitrile-0.5% glycerin (pH 7.6) were suitable as analytical column and eluant, respectively. Nitrate ion, sulfate ion and free oxalic acid could be extracted with water. Total oxalic acid could be extracted with 1% hydrochloric acid. Sample solution was measured by single column ion-chromatograph after 5 fold dilution with water followed by passing through 0.45μm filter. This method was applied to spinach and canned boiled bamboo shoots. In the spinach, the content of oxalic acid was high in the leaves, that of nitrate ion was high in the stems and the roots, and that of sulfate ion was high in the stems.

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The adaptability and precision of the Retention Index (RI), calculated on the conventional Purge and Trap Concentration System(PTC-GC), were examined. The RI values about 9 aldehydes, 10 alcohols and other 16 model compounds were measured five times on two columns of OV-101 and CARBOWAX-20M. The limit of RI values calculated on PTC-GC was 500-1900. This upper limit corresponds to hepatadecanal for aldehyde and hexadecanol for alcohol. The reproducibility of the RI values on both columns was same as that of direct injection GC, and the standard deviations of their RI values were in 0-1.1. Also the reproducibility of quantitative analysis on the PTC-GC was almost same as that on direct injection GC analysis. However, the recovery of compounds having high boiling point or higher polarity was low.

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