The effects of heating conditions, vegetable protein content, moisture and setting conditions on physical properties of kamaboko with commercial vegetable proteins were tested by the determination of jelly strength, softness and expressible water. (1) The firm gel was obtained at 60°C for kamaboko with soybean protein and at 80°C with wheat gluten. (2) When moisture content of the kamaboko with 5% vegetable proteins was adjusted to 68.8 -79.0%, the changes of jelly strength, softness and expressible water of the kamaboko with wheat gluten were somewhat greater than those of the kamaboko with soybean protein. (3) When ground surimi with 5% vegetable proteins was kept at 10°C for 0-48h or at 40°C for 0 -2h followed by heating at 90°C for 30min, the jelly strength of the kamaboko was weaker than that of the kamaboko without vegetable protein. (4) The jelly strength of the kamaboko with soybean protein was considered to be mainly affected by a 3% NaCl-insoluble fraction of soybean protein and that of kamaboko with wheat gluten seemed to be affected by the gel formation ability of wheat gluten per se.

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A new type bioreactor system was developed for continuous vinegar production. Twin bioreactors were assembled from an ethanol fermentor (3l-working volume) and an acetic acid fermentor (2l-working volume) in which Saccharomycodes ludwigii and Acetobacter aceti were predominated, respectively. Both organisms were used as cell suspensions in each fermentor. Optimized conditions for continuous vinegar production were examined with saccharified rice bran medium containing 10% glucose and 1% acetic acid. Rice vinegar containing 6.1 to 6.5% acetic acid was produced at the total residence time of two fermentors of 25.6 to 38.9h and the acetic acid productivity was 3.5 to 5.0g/(l·h), when the medium was allowed to flow through the bioreactors at 128 to 195ml/h. The functions of the bioreactors were maintained constant after a successive use for 55 days. Several advantages with such twin bioreactors for continuous vinegar production were also discussed.

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A few types of noodles were manufactured under several far infrared irradiation conditions in the laboratory. Changes in the inner temperature, the moisture and the gelatinization degree of the raw noodles were measured. Rheological properties such as shear strength, hardness, cohesiveness and adhesiveness of cooked noodles were also examined. Fine structures of raw and cooked noodles were observed with a scanning electron microscope. The rheological tests revealed that the short time exposure of noodles to far infrared irradiation induced the maximal results in any kinds of tests, which was consistent with the observation of the cooked noodle's surface. It was considered that the rigid structure of gluten had been formed at the surface of noodles in the case of the short time exposure to far infrared irradiation. The same positive results were also shown between the gelatinization degree and the scanning microscopic images of the raw noodle's surface.

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A method to estimate moisture and salt contents in butter continuously non-destructively and simultaneously in a process, was investigated. According to the expectation that salt and moisture contents are independently related to specific gravity and the dielectric constant with the first term linear formula, some experiments were carried out to confirm the expectation. Butter with different moisture and salt content was prepared continuously by modulating the injection volume of water and Salt, and its dielectric constant, specific gravity, moisture content and salt content were measured. The dielectric constant was measured with electrodes installed in the outlet pipe of finished butter, and specific gravity was measured with the oscilation density meter installed after a samp1ing pump on the branch line connected to the outlet pipe of butter. The butter ejected from the density meter was analyzed with respect to moisture and salt contents by mean of the drying method and the Mohr's method, respectively. The results of non-salted butter showed that the moisture content could be estimated with the linear regression formula of the dielectric constant. Furthermore the better estimation of moisture content was possible with complex linear regression formula of the dielectric constant and specific gravity. Also, the results of salted butter showed that both the moisture content and the salt content could be estimated satisfactorily by mean of different complex linear regression formula of the dielectric constant and the specific gravity. Accordingly, this estimating system was confirmed to be available for the simultaneous estimation of salt and moisture contents, and for the process control of butter manufacturing.

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The effects of palatinose, fructo-oligosaccharides, coupling sugar, linear gluco-oligosaccharides, branched gluco-oligosaccharides, maltitol, hydrogenated linear gluco-oligo- saccharides and lactulose on the stability of oils in cookies containing δ-tocopherol (δ-Toc) were investigated. The stability was evaluated by the changes of peroxide value (PV) of the oil fraction after baking and storage at 40°C. PV of oils in cookies blended with palatinose, maltitol and lactulose remained low after baking and storage for 7 months. On the other hand, PV of those blended with fructo-oligosaccharides, coupling sugar, linear gluco-oligosaccharides, blanched gluco-oligosaccharides and hydrogenated linear gluco-oligosaccharides remained low just after baking but rapidly rose after 4 months storage. The addition of δ-Toc was effective for prevention of deterioration of oils in the cookies blended with fructo-oligosaccharides, coupling sugar, linear gluco-oligosaccharide, branched gluco-oligosaccharides and hydrogenated linear gluco-oligosaccharides.

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Antioxidative activities of extracts of black sesame and their fractions were examined in comparison with white sesame, using 10-14 domestic strains. The index of the activity was expressed as the days of induction period (I.P.) in the autoxidation of emulsified linoleic acid containing the test samples at 40°C. Averaged I.P. of 80% ethanol extracts of crushed seeds from 5 kinds of black seeds was higher, (35.4±12.9) days, than those from 5 kinds of white seeds, (31.6±10.3) days, but the difference was not significant statistically. I.P. values of water extract from 4 kinds of black seeds and 1 white seed were>30 days, and those from 3 kinds white seeds were<30 days. Water extracts of black seeds was black in color and showed reactions with catechol tannins. The extracts were fractionated by gel filtration chromatography (Sephadex LH-20), by sucessive elution using methanol, 50% acetone and water, with detecting peaks of 280nm absorption. Five fractions obtained were examined for their antioxidative activities and f1 and f3 eluted by methanol and f4 eluted by 50% acetone showed high I.P. values.

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Plasma protein was hydrolyzed with trypsin or pepsin in order to improve solubility and emulsifying activity. Plasma protein was only slightly hydrolyzed with trypsin. Emulsifying activity index (EAI) of plasma protein changed little by the tryptic hydrolysis. After the peptic hydrolysis, EAI of plasma protein decreased to about 50% of the original level. During heat treatment of these hydrolyzates, EAI of the tryptic hydrolyzates decreased, while EAI of the peptic hydrolyzates changed little. The peptic hydrolyzates were fractionatedusing hydrophobic chromatography. The hydrophilic fraction showed lower EAI than that of the peptic hydrolyzates and the hydrophobic fraction showed higher. It was shown that hydrophobic chromatography is effective for the preparation of a material having high emulsifying activity. After the enzymatic hydrolysis of plasma protein, hydrolyzates were ultrafiltrated and the solubility and EAI were measured. These properties were improved under several conditions of pH and ionic strength by the combination of enzymatic hydrolysis and ultrafiltration.

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Growth inhibition of six species of bacteria by allyl isothiocyanate (AIT) and its some derivatives was studied at 30°C on shaking culture to elucidate the relationship between chemical structure of AIT and the inhibitory action. Among allyl derivatives tested, 0.8mM allyl alcohol inhibited the growth on stationary phase of Proteus vulgaris and Bacillus cereus, and 0.8mM diallyl disulfide extended the lag phase of Staphylococcus aureus, Pro. vulgaris, Pseudomonas aeruginosa and B. cereus.However, allyl chloride, allyl cyanide and diallyl sulfide did not exhibit any inhibition. Comparison of the inhibitory activity of alkyl isothiocyanates showed that methyl isothiocyanate was most effective, followed by ethyl isothiocyanate, and n-propyl as well as nbutyl isothiocyanate was less effective. AIT, an alkenyl isothiocyanate was more effective than ethyl isothiocyanate. From these results, it was concluded that isothiocyanate radical is essential for the inhibition, whereas allyl radical is not. Generally, alkyl isothiocyanate of low molecular weight is more active than that of high molecular weight. Alkenyl isothiocyanate is more active than corresponding alkyl isothiocyanate.

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Edible refined oils prepared from four varieties of conventional Japanese soybean seed (Suzuyutaka, Tachinagaha, Tamahomare, Horei) were investigated for the flavor and oxidative stabilities as well as the fatty acid composition. The linolenic acid level in refined soybean oils prepared from Tachinagaha and Horei was low (3%) in comparison with those of Suzuyutaka and Tamahomare (6%). No difference was observed in off-flavor during photo-oxidation of four refined soybean oils, although the oxidative stability of refined soybean oils depended on varieties of soybean seed. The randomization, however, decreased the flavor stability of soybean oil.

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Retention indices of a homologous series of aliphatic compounds on a gas chromatogram were expressed as a linear equation. Fifty three equations for aliphatic compounds, such as alkanals, alkenals, carboxylic acids, alkanones, alkanols and so on, were calculated using a program written in BASIC language to find out possible compounds for unknowns. A retention index I value of an unknown compound measured on an OV 101 (nonpolar column) or Carbowax 20M, (polar column) was compared with those calculated from several linear equations, and the compounds having a small difference between observed I value and calculated ones were displayed on a monitor as a table. In the compounds listed in both tables, the compound identified was displayed on the monitor as the most suitable compound.

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Bifidobacterium growth promoting activity of defatted rice bran hydrolyzed by Aspergillus oryzae (rice bran koji extract) was tested. It was effective as much as yeast extracts known as a Bifidobacterium growth promoting factor. It was found that defatted rice bran was more effective than wheat bran and hatomugi bran as koji material to produce the factor. We isolated the active substances from rice bran koji extract. The active fractions, having stimulants on the growth of Bifidobacterium were separated by ion-exchange chromatography, and those fractions were found to promote the growth of B. longum, B. bifidum, B. infantis, B. adolescentis and B. breve. Low molecular weight peptides in these fractions were suggested to play significant roles as Bifidobacterium growth promoting factor.

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One of the production methods of hydrolyzable starchy material under high concentration was developed by the addition of thermostable α-amylase using a twin-screw extruder, in order to get more useful application on white rice bran. Paddle screw elements were more effective than kneading screw elements during the first extrusion. On the second extrusion with the addition of thermostable α-amylase, screws assembled by only forward elements were the best one, because temperature increase of the extrudate was small during extrusion. The highly hydrolyzable starchy material manufactured in this series of extrusions was completely gelatinized and over 90% of the α-amylase activity was maintained. The starchy material produced by two-stage extrusion process was hydrolyzable up to 50% based on substrate concentration. Moreover, hydrolyzation by the addition of 0.1% (v/w) glucoamylase could be brought to about 85% of the reducing sugar ratio based on total substrate as sugars after 48hr reaction.

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The screening was carried out to find strains in Monascus fungus that would produce a high activity of acid proteinase. Monascus sp. No. 3404 was found to have the highest activity of the enzyme, which was formed by addition of defatted soybean meal to the medium.
The enzyme was purified to homogeneity from the culture broth of this organism grown on defatted soybean meal. The molecular weight of the purified enzyme was determined to be 43000 by gel filtration method and 46000 by SDS-polyacryl amide gel electrophoresis method. The optimum pH was 3.2 and the optimum temperature was 50°C. The enzyme was active on human hemoglobin, milk casein and bovine serum albumin, and Km values for them were calculated to be 0.80, 1.45 and 1.80mg/ml, respectively. The enzyme was markedly inhibited by pepstatin A and chymostatin, and Ki values for them were calculated to be 28nM and 0.13mM, respectively.

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The effects of salt (6.3-8.3%), ethanol (0-2%), glucose (0.3-2.3%) and pH (4.0-5.0) on the growth of 6 species of lactic acid bacteria (Lactobacillus plantarum, L. brevis, L. bavaricus, L. coryniformis subsp. torquens, L. coryniformis subsp. coryniformis, and Lactobacillus sp. 1), which were isolated from salted "Daikon", were studied by using fractional factorial experimental design for factors at three levels. L. plantarum and L. brevis grew in the presence of 6.3-8.3% sodium chloride, while no growth of the other 4 species was observed in the medium containing over 7-3% salt. The growth of L. plantarum and L. brevis was inhibited when the concentration of sodium chloride was increased and when the medium pH was decreased. Ethanol had an inhibitory effect at increased concentrations on the growth of L. brevis, but not on the growth of L. plantarum. Inhibition of growth of L. plantarum and L. brevis was most marked by pH, followed by sodium chloride and ethanol. Effects of glucose on the growth of these lactic acid bacteria (6 species) were not clearcut.

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A bioreactor consisting of 2 columns of porous ceramics, onto which Acetobacter aceti IFO-3284 was adsorbed, was applied to the continuous production of vinegar from a synthetic medium containing ethanol or from Unshu mandarine orange wine. The bioreactor was operated under either open or closed condition with the synthetic medium containing varying amount (428-8.80% (w/v)) of ethanol. The maximum concentrations of the acetic acid obtained were 8.10% from 8.41% (w/v) under the open condition, and 8.39% from 7.24% (w/v) under the closed condition. The maximum conversion ratios of acetic acid from ethanol were 81.1% under the open condition, and 98.3% under the closed condition with the synthetic medium. Using the bioreactor, the vinegar without problem in taste and flavor was obtained from Unshu mandarine orange wine under the closed condition. The amount of supply of oxygen under the closed condition was enough to oxidize ethanol in the substrate.

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