Rice has been used as an ingredient for making rice crackers in Japan. The quality of rice as a material for cracker was evaluated mainly by the degree of expansion. However, not much has been known about the component of rice to relate the degree of expansion of rice cracker. So, relationships between physicochemical properties of non-glutinous rices and the degree of expansion of rice crackers were investigated using eight varieties which differed in amylose content (15.8-31.0%) of rice starch and protein content (6.11-9.32%) of milled rice. The degree of expansion of the rice crackers was negatively correlated with either the amylose content ranging from 21.3 to 31.0% or the protein content ranging from 7.4 to 9.32%. The amylose content had a greater influence on the degree of expansion of the rice crackers than the protein content. Starch contents of the milled rices decreased with an increase in those protein content. SDS-PAGE of the milled rice proteins showed similar patterns. The acid-solubility (0.25N HC1, 55°C) of the dried rice cakes, which was correlated with those degree of gelatinization, showed high correlation with either the degree of expansion of the rice crackers (r=0.977^**) or the amylose content (r=-0.851^**). From these results, it was concluded that the degree of expansion of rice crackers was affected by the starch content of milled rices and by the amylose content of rice starches which related to the degree of gelatinization.

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Basic information for preparing tasty kombu soup-stock was obtained by studying the relationships between the amount of components in the soup stock and the extraction time(from 1 to 90min) and temperature (from 5 to 95°C). The longer the extraction time and the higher the temperature, the greater was the quantity of components extracted. The extracted amount (Y) of each component at each temperature is well defined as a function of the extraction time (X) by the following relationship:
where a is the slope of the extraction curve during the initial stage, and b is the asymptotic value, i. e., the maximum amount extracted. Values of each component were plotted against each extraction temperature, and the apparent activation energywas calculated. The apparent activation energy for each component was also obtained from the b values. By comparing these values for apparen activation energy, we could evaluate the temperature dependence in the extraction rate of each component. The temperature dependence in the initial stage of extraction was greatest in the order of mannit, total extract, K⁺, Cl^-, and total N. The components having the greatest temperature dependence for maximum extracted amount were Ca²⁺, Glu, Mb²⁺, PO₄^3-, and total extract.

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To examine intestinal absorption of fat in calcium-added chocolate, we prepared standard chocolate and calcium added chocolate. Male Sprague-Dawley strain rats were fed on one of the semi-purified diets containing 60% standard chocolate or calcium added chocolate for a week. The results were as follows. 1) Increased fecal excretion of fat and calcium was observed in the calcium-added chocolate group. 2) Especially, the absorption of stearic acid and palmitic acid in the calcium-added chocolate group was significantly lower than that of the standard chocolate group. These results suggest that absorbed calorie of calcium-added chocolate is lower than that of standard chocolate.

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The volatile compounds of black tea were investigated by using gas chromatography (GC) and gas chromatograph-mass spectrometry (GC-MS), with comparing the methods for preparing odnr concentrates. Thirty-nine alcohols, 31 aldehydes, 28 ketones, 17 esters, 7 lactones, 4 phenols, 3 furans and furanones, 29 hydrocarbons and 14 miscellaneous compounds were identified. The odorconcentrate prepared by Porapack Q column adsorption method followed by elution with ethyl ether: isopentane (6:4) solution had a typical black tea like odor. On the contrary another odor concen trate prepared by simultaneous distillation extraction (SDE) underreduced pressure had a steamed tea leaves like odor and an astringent bitter odor. Flavor index, which was the ratio of the sum of 20 peak areas of group II, i.e., linalool and its four oxides, benzaldehyde, geranin1, etc. to that of 12 peak areas of group I, i.e., hexanal, (Z)-, (E)-2-hexenal, (E, Z)-, (E, E)-2, 4-heptadienal, pentanol, hexanol, (Z)-3 -hexenol, etc., Was 2.63 for the Concentrate prepared by Column method and 1.22 for SDE method.

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Sensory test and compositional analysis were carried out for 28 Japanese well waters. Factor analysis for sensory attributes allowed the simplification of the variability among the samples into five factors capable of clear interpretation. These five factors containing 65.7% of all information obtained from the samples were refreshing, mouth feel, aroma, aftertaste, and astringent. Water taste was successfully expressed, by a linear discriminant function, in terms of a limited number of key components as follows:
Index=-9.43+1.01 O₂+0.55logSi+0.83 logHCO₃--0.09Mg(mg/l)
The classification error-rate of this index was 18.5%. Positive index means that a sample is tasty. Three components carrying the plus sign, i.e. O₂, Si, HCO₃^-, is considered attributable to a good taste. On the contrary, Mg is seemed to confer a bad effect.

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The lemon pectin was hydrolyzed by a pectinase or H2SO4. The antibacterial activity of the hydrolyzates against Eschericia coli was investigated with culture media containing 0.1 to 1.0% of the hydrolyzates at pH5.5. While the undegraded pectin had no antibacterial activity, both hydrolyzates showed clear activities. The enzymic hydrolyzate showed stronger activity than the acid hydrolyzate. Both hydrolyzates were chromatographed on DEAE-Sephadex A-50 and Sephadex G-25 column and separated into three oligogalacturonic acids having various degrees of polymerization (DP2 to 4). The properties of both hydrolyzates differed from one another in the amount of methoxyl groups and neutral sugars. The acid hydrolyzates did not contain the methoxyl groups and neutral sugars. The antibacterial activity of the enzymic hydrolyzates seemed to be due to a) free undissociated carboxyl groups, b) methoxyl groups, c) degree of polymerization of oligogalacturonic acid and d) neutral sugars. The a), b) and c) were principal factors, but d) was not, because concentration of sugars in the enzymic hydrolyzate was low. The antibacterial activity increased with increase of amount of methoxy groups and degree of polymerization. The enzymic hydrolyzates showed strong antibacterial activity against bacteria except lactic acid bacteria, and showed weak or non-activity against yeasts and fungi.

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The effects of synthetic food colorants on oxidative deterioration of soybean oil were investigated. The oxidative deterioration of oil were apparently promoted by an addition of fast green, indigo carmine or phloxine. Especially, on addition of phloxine, oxidation of oil and decomposition of tocopherol in oil during storage at the window were remarkable. But the addition of ponceau-4R, amaranth, tartrazine and sunset yellow had no effect on oxidative deterioration of oil. On the other hand, addition of catechin and gallic acid suppressed oxidative deterioration of oil promoted by phloxin

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Pre-cultured lactic acid bacteria, Lactobacillus sp. SK-1001 was injected into the porcine muscle (longissimus thoracis) at a level of 10⁶cells/g. The meat was cured and fermented at low temperature (5°C) for 3 weeks. Changes in the microorganisms, colors and physical properties of the fermented meat products and protein degradation in the products were investigated each week, and the following results were obtained: Microflora in the products turned into lactic acid bacterial flora after one week. It was confirmed that the growth of Staphyrococci and coliforms was inhibited. The pH value (5.50) in the interior of the meat decreased to 4.97 after 3 weeks. The color of the meat differed significantly after fermentation for 3 weeks. Desirable color formation was observed, and residual nitrite content decreased during the fermentation period. The cohesiveness and gumminess of the meat increased significantly with the period of fermentation. Under these experimental conditions, protein degradation in the meat was not observed. From these results, it appears that hams fermented at 5°C with psychrotrophic lactic acid bacteria, Lactobacillus sp. SK-1001 are safe and acceptable.

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The steam injection type direct heating sterilizing method is a typical method among sterilizing operations for liquid foods, together with the plate type indirect heating method. In addition, sterilization is a vital operation for food production and a research on the certainty of this sterilizing method has been required. Despite those facts, however, the phenomena that steam injected at high speed into liquid foods abruptly mixes followed by condensation, and that heating to the sterilizing temperature and holding for the required time are performed in a holding tube, have been rarely studied. Accordingly, the sterilizing efficiency resulted from these phenomena can hardly be determined beforehand. Therefore, a steam injection type sterilizing machine for experiment was assembled using a single nozzle which has been used typically. The details of uneven temperature distribution in the holding tube were measured with multi-points and real-time measuring method as well as velocity variations. In this way, the negative effect of these factors on the sterilization was examined. Moreover, similar measurements were carried out on a practical machine, and reproducibility and variation of the sterilizing effect due to the machine size were investigated.

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Sensory test and compositional analysis were carried out for 37 Japanese and 6 imported commercial drinking waters. Factor analysis for sensory attributes allowed the simplification of the variability between samples into five factors capable of clear interpretation. They were softness, refreshing, aftertaste, mildness, and smell. They contained 75.3% of all information obtained from samples. Water taste was successfully expressed, by linear discriminant function, in terms of a limited number of key components.
Index=-2.30- 7.20 DM-3.81 DM2 + 1.25log Si + 1.36 logHCO₃^--0.09 Cl^--0.09 Mg(mg/l)
In this index, the informations of sensory evaluation about smell were introduced into this model, since the smell was well known to affect badly against the taste of water. For this purpose two dummy variables were adapted, DM1 and DM2. Consequently, the cross-validation error-rate was reduced to 9.1%. In the case of positive index, it means that the sample is tasty. Two components having the plus sign, i.e. Si, HCO₃^-, is considered attributable a good taste. On the contrary, Cl^- and Mg are seemed to confer a bad effect.

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For the purpose of utilizing Okara (a byproduct of Tofu) as a cellulosic biomass, enzymatic saccharification of Okara was conducted by using a Continuously Stirred Tank Reactor (CSTR) with a working volume of 1L, and operational parameters such as Okara concentration (S₀) of its suspended liquid, pH and temperature were examined. Some measurements revealed that the producing temperature and the specific heat of Okara were 80°C and 3.80kJ/kg·K, respectively, and shaft-torque to stir the Okara-suspended liquid in the reactor increased largely at S₀=350 g/L. The torque and the temperature of Okara after including water which was calculated from the thermal properties of Okara could help us to determine a suitable S₀ for saccharification in this reactor to be 350g/L. Also from a saccharification experiment using 1% Cellulase (Onozuka 3S) solution, operational pH and temperature to obtain a higher reaction rate were found to be 40°C and 40°C, respectively, and accordingly, the reaction rate was calculated to be 103mg/L·h for S₀=350g/L.

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Kyushu Uniuersity, 6-1O-1, Hakozaki, Higashi-ku, Fuleuoka 812 Heated and heated-sheared starches (corn, wheat, potato and sweet-potato starches containing 20 and 25% moisture(dry basis)) at l50°C were prepared with a flow tester and then cold water solubility and the degree of gelatinization were compared. For heated samples, cold water solubilities of corn, wheat, potato and sweet-potato starches containing 20% moisture were only 3.5, 3.7, 1.8 and 5.6%, respectively while for heated-sheared samples, they were 48.3, 28.5, 33.2, and 51.0% (as the average value of 30-500kg/cmcm² samples), respectively. For heated samples, the degrees of gelatinization of corn, wheat, potato and sweet-potato starches were 38.4, 40.6, 24.7 and 28.8%, respectively although for heated-sheared samples of starches, they increased up to 85.6, 90.3, 89.8 and 84.0 (ast, eaverage value of samples treated at 30-500kg/cmcm²), respectively. The trends were same for starch samples containing 25% moisture. The results of the present experiments conducted that the shearing-force on starch melt may strongly influence the increase of cold water solubility and the degree of gelatinization of low moisturized starch under heating.

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The binding isotherms of aliphatic medium-chain carboxylate anions (octanoate and decanoate) to soy β-conglycinin have been measured by equilibrium dialysis at 30°C in a Tris-HC1 buffer, pH8.0, containing 10mM 2-mercaptoethanol. It has an intrinsic binding constant of 663M^-1 for decanoate at 30°C. The number of binding sites on the native β-conglycinin was estimated to be 3. Decanoate binding was independent on the ionic strength and temperature of the incubation medium. Decanoate binding was decreased when reductant was removed from the medium. The native tertiary structure with reduced sulfhydryl group was required maximal binding of decanoate to β-conglycinin. A decrease in decanoate binding occurred when pH of the medium was raised from 8.0 to 10.0, indicating that the presence of positively charged protein sites were required for the binding. The binding affinity was enhanced by an increase in chain length of the ligand, suggesting that the major binding energy is derived from hydrophobic interactions between non-polar tail of fatty acid and hydrophobic regions of protein.

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This study was carried out to determine whether or not halotolerant and halophilic histamine (Hm)-forming bacteria (HH bacteria) produce non-volatile amines in meat during the traditional processing of fermented sardines with rice-bran (FSR). HH bacteria in FSR for 6 months increased in a number to more than 10⁴/g. Putrescine, Hm and tyramine content markedly increased in the meat of FSR after 6 months. The isolates of HH bacteria from the raw sardine were identified as Staphylococcus, Micrococcus, Vibrio, Pseudomonas III/IV-NH and Pseudomonas III/IV-H. The isolates from FSR after 6 months were identified as Staphylococcus, Micrococcus and Vibrio.

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Among several sensory characteristics to evaluate the quality of miso (fermented bean paste), aroma is the most difficult one. If results of chemical analysis of miso aroma could be transformed into numerical terms, the evaluation of miso may become easier. Therefore we investigated relationship between aroma components and sensory scores of rice-miso by multiple regression analysis. Thirty-four rice-miso exhibited at the National Miso Competition were used as the samples. Each peak area of the aroma components detected by GC analysis was normalized at its ratio to the peak area of the internal standard. The normalized values were used as an independent variable and the sensory scores were used as a dependent variable. High correlations with sensory scores were obtained for maltol and HEMF. As the result of a multiple regression analysis, maltol was selected at step 1 with the coefficient of determination (R²) of 0.509. At step 7, R2 of 0.804 was obtained. Thus about 80% of the variability in the sensory scores could be explained by the seven components. The results suggested that the multiple regression model using aroma components may be applied to the evaluation of aroma qualities of rice-miso samples exhibited at the National Miso Competition.

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Luteolin was isolated as a lipase inhibitor from Cassia mimosoides var. nomame. During an investigation on the inhibitory effects of the other related flavonoids on lipase, flavonols (kaempferol, myricetin and quercetin) exhibited activity comparable to that of luteolin, while their glycosides, flavanones and flavan-3-ols showed negligible activity. The inhibitory activity on lipase was also shown by quercitrin gallate, epigallocatechin gallate, isoflavones and chalcones.

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