The slowest heating point is great importance for determining temperature of a canned food in sterilizing process. To obtain the point, the temperature profiles for solid food in oil in the can were estimated by numerical calculation from fundamental equations at unsteady state in consideration of a natural convection of the oil covering solid food. The position of the slowest heating point in the canned food in oil was obtaind accurately and an empirical equation for the position was obtained numerically under various operating conditions. The calculated temperature profiles and the position of the slowest heating point were in sufficiently good approximation to the experimental ones.

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Mechanical compression properties of gels were investigated by two methods; jelly strength test and uniaxial compression test. The gels used in the present study were agar-agar gel, konjac gel, gelatin gel, heavy oil (A) gel, and salad oil gel. Apparent jelly strength JS obtained with a Nikkansui's measuring apparatus was correlated well with a gel weight concentration by a equation (s_g-s_g0)n for five kinds of gels tested. Both apparent elastic modulus E and rupture force σ_b obtained from the force-deformation curves of uniaxial compression test were also correlated well with apparent jelly strength JS in the manner. Apparent elastic modulus E was directly proportional to rupture force σ_b for agar-agar gel, gelatin gel, heavy oil (A) gel, and salad oil gel tested. The proportional constant, "compression rupture index" β_i, is demonstrated to be useful as a parameter for evaluating the physical properties of gels.

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To compare the difference of odor quality in peel oils of acid citrus, the essential oil was prepared by solution extraction from five kinds of acid citrus; Lemon (Citrus limone), Lime (Citrus aurantifolia), Sudachi (Citrus sudachi Hort. ex Shirai), Yuzu (Citrus junos Tanaka) and Kabosu (Citrus sphaerocarpa Tanaka). Each oil was separated into fractions of hydrocarbon and oxygenated compounds through a silica gel column, and analyzed by gas chromatography (GC) and gas chromatography-mass spectrometry (GC/MS). As the volatiles, 72 components in Lemon, 76 components in Lime, 69 components in Sudachi, 71 components in Yuzu and 77 components in Kabosu were identified. As these oxygenated fractions had the characteristic aroma of the peel oils, odor quality of each fraction was estimated on the basis of a logarithmic odor unit value (log U_o). The components contri-buted to the aroma of the each peeI oil were selected. Then the similarity of odor quality among peel oils examined were estimated by sensory evaluation and multivariate analysis. These results lead to the conclusion that log U_o is the most useful index for evaluating odor quality.

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Changes in the physical property of a series of bread (prepared by an automatic home bakery) during storage have been investigated using a continuous minute deformation method of the multi-biting test. Changes in the apparent hardness of bread crumb during storage were expressed by increase of slope in the linear relationship between the biting ratio (10-35%) and the work load of the plate type plunger measured by a continuous minute deformation method of the multi-biting test. Gradient of the linear formula obtained between the biting ratio and the work load of the plunger was increased with storage. This gradient of the linear formula of bread with storage was reduced by increasing the amount of water in the bread. Resilience of bread crumb can be discussed by the slope of the linear relationship between the biting ratio and the ratio of work load of the plunger in specified biting ratio vs first biting ratio measured by a continuous minute deformation method of the multi-biting test. The slope of this linear relationship was decreased with storage of the bread. Changes in the physical property due to the degradation of starch in bread with storage were also discussed by the parameters (especially correlated to the viscosity characteristics) of the multi-biting test of liquid samples prepared from the bread.

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The baking industry has traditionally used butter not only for its rich flavor, but its plasticity lubricating ingredient mixtures and encapsulating protein, moisture, or air at various stages during and after the manufacture of a product. The laminated dough such as Danish, French and puff pastry, consists of many thin alternate layers of dough and fat, which upon baking, give a separation of strata and an open network of crisp and flaky layers. It is recognized that the appearance of baked pastry, mainly its volumetric change, may be related to physical properties of butter such as solid fat content and hardness. The structural changes of butter, which depend on its manufacturing method, was observed through cryo-scanning electron microscope and polarization microscope. Relationship between the structures, volumetric changes of French pastry after baking and their physical properties were investigated using conventional batch churned butter as a control and butter manufactured by newly developed continuous process using high fat cream as raw material whichc ontained over 82% of milk fat. More volumetric change was consequently endowed with higher hardness of butter whose structure is made up of numerous tiny crystal interlocking liquid phase.

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We have previously proposed a method for predicting optimum cooking time of potatoes, and have applied the method to other ten species of vegetables. In this study, we investigated the effects of harvest time, freshness and position of segments of carrot and Japanese radish on softening rate and optimum cooking time. The softening of all the carrot samples and Japanese radish samples was approximated by first order kinetics, and the softening rate constant was calculated. The rate constants at 99.5°C (k_99.5) of carrots and Japanese radishes varied in the range of 0.211-0.259 and 0.193-0.274 dependent on the harvest time and position of the segments, and in the range of 0.151-0.202 and 0.147-0.201 dependent on freshness, respectively. For example, k_99.5 of carrots and Japanese radishes decreased when they had been stored at room temperature for several days. The calculated cooking times for the stored samples were a few minutes longer than those for fresh samples, but the difference in the cooking time was not distinguished by a sensory test. From these results, the method for predicting the optimum cooking time could be applied to the root vegetables of various conditions.

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To get fundamemtal understanding on production of commercial frozen whole egg of uniform qualities, changes in functional properties and soluble protein composition resulted from freezing of pasteurized and unpasteurized commercial liquid whole egg were studied. The variance of function properties among samples, frozen and stored at -20°C, tended to be small after 60 days of storage, and the variance might be more obvious in pasteurized egg than in unpasteurized egg. Increasing rate of apparent viscosity of frozen whole egg was affected not only by storage temperature but also by freezing temperature. Transmission electron microscopy pointed out that aggregation of lipoproteins occured in frozen whole egg. The aggregation emerged more clearly in thawed egg magma than in freeze-dried frozen egg, suggesting that it proceeded during or after thawing. Electrophoretic profile of the soluble proteins of whole egg, prepared by treatments without ultracentrifuge and fractionated by gel-filtration on Sepharose 4 B, showed aggregation of lipoproteins during frozen storage. The fractionation patterns of soluble proteins is considered to be useful to monitor denaturation of frozen whole egg magma.

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The inorganic elements of brown and milled rices of following varieties were measured: Koshihikari, Sasanishiki, Akitakomachi, A (high amylose rice), B (high protein rice) and Nipponbare. Minerals were determined with lithium metaborate fusion-inductively coupled plasma (ICP) atomic emission spectroscopy. The following results were obtained. Koshihikari has the lowest nitrogen contents among these rices, and has a tendency to show the high ratio of magnesium and phosphorus in the milled rice. It is worthy of note that silicon content of Koshihikari showed higher and the ratio was lower than Sasanishiki, Akitakomachi and Nipponbare. The ratio of manganese in the milled rice differed little among Koshihikari, Sasanishiki, Akitakomachi and Nipponbare, but it was low in A (high amylose) and B (high protein). It was remarkable that the ratio of magnesium, phosphorus, potassium and manganese in B (high protein rice) was lower than the other. The ratio of zinc, sulfur, calcium, carbon and nitrogen in each milled rice was high as 59-100%.

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DNA hybridization method was applied to identification for meat species (bovine, pig, rabbit, chicken, horse and sheep) using digoxigenine labeled probe. The samples were obtained from the meats which were heated at 80 or 120°C for 30min. DNA extracted from a sample was spotted on a nitrocellulose membrane., followed by crosslinking to the membrane under vacuum at 80°C for 2hr. This filter was incubated in hybridization solution with probe DNA at 42°C for overnight. Colour reaction with BCIP and NBT were executed according to the manufacture's instruction. The probes for bovine, pig, horse and chicken were certainly hybridized with target DNA. However other probes showed cross-reaction in heated meats.

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The changes in free amino acid contents during ripening of normal tomato fruits and mutant, ripening inhibitor (rin), were analyzed. In normal tomato, glutamine was most abundant before ripening and tended to decrease as the fruits ripened. Also decrease in γ-aminobutyric acid and increase in glutamic acid were observed simultaneously. In case of ripening mutant (rin), glutamine was most abundant before ripening, too. However, because of its ripening process was strongly inhibited genetically, the changes in glutamic acid, γ-aminobutyric acid and glutamine were slower than normal ones. From these result, it was found that glutamine was a predominant free amino acid before ripening. A tendency of decrease in glutamine during ripening was also observed.

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Inhibitory effects of volatile mustard extract containing allylisothiocianate (AIT) as a primary constituent on the growth of yeasts isolated from high-sugar foods were studied in water activity (Aw) range of 0.97 to 0.86. The growth of all the tested yeasts were completely inhibited at all Aw values by using volatile mustard extract, while they grew at Aw 0.97 to 0.86 or 0.89 in the control. Concentration of AIT in headspace was equilibrated (2μg/ml) in 24 to 48hrs. Minimum inhibitory concentrations of AIT on these yeasts were 3-15ng/ml.

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Effect of primary processings on 5'-nucleotide content in seven species of mushrooms including Hygrophorus russula (Sakurashimeji), Lyophyllum fumosum (Shakashimeji), Armillariella mellea (Naratake), Lentinus edodes (Shiitake), Lactarius hatsudake (Hatsutake), Ramaria botrytis (Hokitake) Grifola frondosa (Maitake), were examined. Three different conditions were used to extract 5'-nucleotide from mshrooms. There was significant difference in 5'-nucleotide content among species of mushrooms. Lac. Hatsudake, Lyo. fumosum, and G. frondosa contained more 5'-nucleotides than H. russula and R. botrytis. 5'-Nucleotide contents of mushroom which desalted after salting stock were extremely low. No significant difference in 5'-Nucleotide of seven species of mushrooms was found among drying methods. Extraction periods with boiling water had no effect 5'-nucleotide contents. On the contrary the soaking for three hours before extraction with boiling water decreased the contents. Seven species of mushrooms showed similar change in the content of guanosine-5'-monophosphate.

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The effect of extracts of some vegetables on proliferation and immunoglobulin (IgM) secretion of human-human hybridoma cell lines (HB 4 C 5 and SI 102) in a serum-free medium was examined. The aqueous dialyzates of broccoli, carrot, Chinese chive, chingentsuai, kinusayaendo, oyster fungus, spinach and sweet potato promoted the proliferation of HB 4 C 5 and SI 102 cells. The relative proliferation-promoting activity of these dialyzates was about 20-40%. A similar proliferation-promoting activity was also found in the ethanol- and dimethyl sulfoxide (DMSO)-soluble extracts of oyster fungus, kinusayaendo, Chinese chive and spinach. The aqueous dialyzates of oyster fungus, Chinese chive, sweet potato and carrot, the ethanol-soluble extracts of oyster fungus, kinusayaendo, and the DMSO-soluble extracts of oyster fungus, Chinese chive, kinusayaendo and nigauri promoted the IgM secretion of HB 4 C 5 cells.

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The rapid and quantitative analysis of free quercetin in vegetables and fruits was studied. High-performance liquid chromatography (HPLC) techniques after preparation with Sephadex LH-20 were found to be suitabie for determining it and could be applied even to the crops containing small amounts of quercetin such as orange, potato, pea and celery. Onion contained the largest amount of free quercetin in the examined vegetables and fruits and its content was 29.1μg per 100g fresh weight. The crops in Liliaceae such as garlic and leek in addition to onion contained free quercetin relatively in large quantity. Quercetin in onion was almost completely localized upon the first and second scales from exterior, and the contents in the two scales were approximately 90% of all the parts. Quercetin was found to be stable when heated to 210°C for 20 min, but it was unstable to light. When it was illuminated with 15000 1x, the contents rapidly decreased and reached to half of the origital contents after 48h.

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The creep and recovery behaviors of the agar gel with the porosity below 20% were expressed by a four-element model consisting of 2 springs and 2 dashpots. Experimental values of recovery part fitted well to the predicted curve. The non-recoverable instantaneous deformation and the non-recoverable retarded deformation were not included in the behavior. The behavior of the gel with the porosity above 20% was expressed by a five-element model consisting of 2 springs, 2 dashpots and 1 slider. Expermental values of recovery part fitted well again to the predicted curve, but the instantaneous deformation was not recovered completely. The residual deformathon induced by this cause corresponded to a slider in the model (the P component: P, plastic, means non-recoverable). When air-impregnated gels with various porosities were compared, the contribution of the P component obviously increased in the gels with the porosity values higher than 20%. The P component was divided into P 1 (instantaneous) and P 2 (retarded) for the detailed examination. The change of the P component was represented by that of P 1, and P 2 remained unchanged with the increase of porosity. From both micrographic observation and model calculation, the distance between the adjacent surface of neighbouring air bubbles just above the critical 20% porosity was estimated to be 0.07mm and corresponded to one third of mean bubble diameter.

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Commercial proteases suitable for soymilk-curd production by limited proteolysis with immobilized enzyme reactor were selected from three plant and a microbial proteases. Limited proteolysis of soy-protein with the enzymes at 30, 5 and 0°C was examined by an electrophoresis. Two commercial preparations of papain and a preparation of bromelain, which were plant proteases, limitedly digested native soyprotein even under the low temperature conditions. The soy-protein solution and soymilk treated with the plant proteases at 5°C gave curd by heat treatment. The plant enzymes were immobilized on SP-Sephadex C-25. The immobilized enzymes digested the soy-protein similarly to the free enzymes. Soymilk-curd was also obtained from the soymilk hydrolyzed with the immobilized enzymes.

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The storage stability of carotene prepared from red and green pimentos was investigated as follows. (1) The stability of β-carotene was observed in different solvents which were methanol-ether, methanol-tetrahydrofuran, acetone-ether, and tetrahydrofuran. The best solvent for conserving β-carotene was methanol-ether. β-carotene in acetone-ether was remarkably destabilized by the scattering light in the laboratory. (2) The extracts of carotene from the lyophilized powders of red and green pimentos were preserved for four days at room temperature. The relative stability of carotene from the red pimento was 100% in methanol-ether, whereas that from the green pimento was only 38% in acetone-ether. The results of the preservation of lyophilized powders at 25°C showed a similar tendency to those of the preservation of carotene extracts. The retention of carotene was 82% after preserving the red pimento powder for 80 days, while it was 58% for green pimento powder after 74 days. (3) The model experiment using β-carotene and chlorophyll showed that β-carotene was more stable in an acetone-ether solution containing chlorophyll than in a solution not containing chlorophyll.

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Soymilk was found to stimulate IgM production in human-human hybridoma HB 4 C 5 cells cultured in serum-free ERDF medium supplemented with insulin (I), transferrin (T), ethanolamine (E) and selenine (S) (ITES-ERDF). The activity for immunoglobulin production stimulating factor (IPSF) was recognized in the acid precipitable fraction. The activity was observed in a peak obtained by fractionation on DEAE-Toyopearl 650M. Molecular size of the IPSF was estimened to be approximately 290kDa by gel filtration on Superose 12 HR. The susceptibility of the IPSF to heat or trypsin treatment suggested that it was a proteinous substance. Soymilk also stimulated IgM and IgG production in human lymphocytes cultured in ITES-ERDF medium.

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Whey protein concentrate (WPC) hydrolysates were prepared with trypsin and treated with microfiltration (MF) and/or ultrafiltration (UF) membrane. HPLC and the immunoreactivity test in vitro (inhibition enzyme-linked immunosorbent assay: inhibition ELISA) were performed on these hydrolysates. Although the insoluble materials were removed from the hydrolysates, no differences were recognized in the patterns of HPLC before or after MF treatment. The main peaks of fraction obtained by MF membrane treatment showed a molecular weight range of 1000 to 6000. On the other hand, fractions by UF membrane treatment were between 1000 and 3000. From the results of the inhibition ELISA, it was recognized that the antigenicity of fractions after UF membrane treatment dropped fron 1/30 to 1/200 compared with the WPC hydrolysate.

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The growth of hypocotyls of thick bean sprouts was examined using the rotary-type box cultivation method from an economical standpoint, by measuring yields, hardness, and color and moisture contents of hypoeotyls as indices of freshness, and total vitamin C content. After steeping in water for 5h at 28-300°C, the raw beans were germinated on a germinating floor (28-30°C) for 2 days and put in the rotary-type cultivation box, and then was water-sprayed at arate of 1l/min every 8h for 10min with 5rpm or 10rpm of rotational movement. By the rotary-type cultivation box method, a low speed rotation at 5rpm led to better growth than high speed rotation at 10rpm. This cultivation method with both rotatlon speeds was judged unacceptable compared with the ordinary method because the yield was markedly reduced, the hardness of hypocotyls was slightly excessive, moistuse content was reduced so much and surface color became yellow. These changes of the hypocotyls led to loss of freshness. The unacceptability of this method was more obvious at high rotation speed than at low speed. The total vitamin C content increased sharply and, thus this cultivation method is effective at least in this regard.

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