Horse mackeral (Trachurus japonicus), frog flounder (Pleuronichthys cornutus), japanese whiting (Sillago japonica), hard clam (Meretrix lusoria), arkshell (Scapharca broughtoni), and scallop (Patinopecten yessoensis) were subjected to various drying processes to investigate the alteration of their eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) levels in each dried product. Dryings by hot drier, far infrared and microwave ovens were examined. On each sample, lipid content per unit increased, because water content of these decreased. But percentages of EPA and DHA in the lipids were not affected, and the peroxide value in case of drying by far infrared and microwave ovens did not impair the quality. These results suggest that dried products of fishes and shellfishes include more amounts of EPA and DHA than perishables. So these products should be rediscovered as effective functional foods for human health.

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The changes of fibrinolytic activities in various okara nattos (ON) fermented by Bacillus subtilis were investigated at different water contents, temperatures, inoculum sizes, nutrients and types of okara. The properties of fibrinolytic enzyme purified from ON were also investigated. The protease activity and fibrinolytic activity in ON and natto during the fermentation were different, and both activities in ON were more than 2.5-fold higher than those in natto at 25 hrs to 30 hrs of fermentation. The fibrinolytic activity in ON having 80% moisture was higher than that having 60% moisture under the same conditions of fermentation. The fibrinolytic activities in ON fermented at different temperatures (30, 37 and 45°C) for 25 hr were 550, 1105 and 525 CU/g, respectively, and that in ON at 37°C was the highest. The fibrinolytic activity in ON fermented for 15 and 25 hr showed higher values at larger inoculum size. The fibrinolytic activity in ON was little affected by nutrients (1%, 10% soy milk and 1% glucose) added to okara. When okara, grounded okara smaller than 30 mesh, and the endosperm and seed-coat prepared from okara were fermented at 37°C for 24 hr, fibrinolytic activities of these were 870, 1065, 725 and 960 CU/g, respectively. The fibrinolytic enzyme partially purified from ON was about 30000 in molecular weight on SDS-PAGE. The activity was stable in the range of pH 7.0 to 10.0, and remained 50% by heating the enzyme for 10 min at 60°C. The enzyme also hydrolyzed D-Val-Leu-Lys-pNA as a synthetic substrate, and its activity was strongly inhibited by DFP.

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We have investigated the changes in flavor of a coffee drink during sterilization heating. Gas chromatography-Olfactometry (GC-O) revealed that five potent aroma compounds (2-furfurylthiol, methional, 3-mercapto-3-methylbutyl formate, β-damascenone, and skatole) made significant contributions to the difference between heating and non-heating. Furthermore, the behavior of these five aroma compounds was studied in detail using a model system. The residual ratios for these compounds after heating were 0.3-79.0%. Especially, the three sulfur compounds showed low ratios (2-furfurylthiol:3.6%, methional:26.0%, 3-mercapto-3-methylbutyl formate:0.3%). The volatile compounds obtained from 2-furfurylthiol, methional, and 3-mercapto-3-methylbutyl formate after heating included difurfuryl disulfide, which was accompanied by 2-furfural and 2-furfuryl alcohol, dimethyl disulfide, and 3-mercapto-3-methylbutanol, respectively. These results suggested that potent aroma compounds in a coffee drink were changed by oxidation, thermal degradation, and/or hydrolysis during heating.

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The effectiveness of aminopeptidase produced by Aeromonas caviae T-64 on accelerating Gouda cheese ripening was studied. After 8 weeks of ripening, flavor of Gouda cheese treated with the peptidase in combination with Neutrase (NA) was enhanced significantly (p<0.05) compared with the untreated control cheese (C). After 12 weeks of ripening, a synergic effect of the aminopeptidase with Neutrase on flavor development was observed in NA of which flavor was significantly (p<0.05) intense compared with the cheese treated Neutrase alone (N). Protein hydrolysis measured by trichloroacetic acid soluble N and sulphosalicylic acid soluble N (SSA-N) was also enhanced by the addition of Neutrase and the aminopeptidase. Capillary electrophoretic analysis of the enzyme-treated cheeses revealed that Neutrase accelerates hydrolysis of para-K-casein (CN), βA₁-CN and βA₂-CN so that the 55, 85 and 70% of those caseins were hydrolyzed during 12 week maturation. Free amino acid composition in the cheese NA was similar to those of N and C, whereas high SSA-N in the cheese NA compared with that of the cheese N indicated that the aminopeptidase increased the amount of amino acids.

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In order to evaluate the effect of lipoxygenase (LOX) on the sensory taste of tofu, relationships between the contents of several components (protein, total lipids, free sugars, isoflavones, total carbonyl compounds and hexanal) and the sensory taste of tofu made from normal or LOXs-deficient soybean cultivars were investigated. The tofu made from Suzuyutaka (normal cultivar) tasted sweeter and more mouthful (rich) compared with those from LOX-2, 3-deficient Yumeyutaka and LOX-1, 2, 3-deficient Ichihime. No difference in the degree of undesirable taste could be detected among the tofus made from the three soybean cultivars by panel. The three different tofus were similar in their contents of protein, total lipids, free sugars (sucrose, stachyose, raffinose, glucose) and isoflavones. The total carbonyl compounds and hexanal contents in the tofu of normal soybean Suzuyutaka were much more than those of LOXs-deficient soybeans (Yumeyutaka and Ichihime). These results suggest that oxidation products of unsaturated fatty acids by LOX contribute to the mouthfulness (richness) for the taste of tofu, and strengthen sweetness in the presence of free sugars by contrast effect.

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Hasukappu (Lonicera caerulea L.), belonging to Caprifoliaceae, is perennial shrub and is naturally distributed in Hokkaido, Sakhalin and Siberia. Since 1973, it has been cultivated in Hokkaido. In order to develop processed food for Hasukappu, the chemical composition and characteristics, ie., Brix, pH and a berry weight, of three strains and two samples on the market in Hokkaido were investigated. The berries contained calcium (38.4mg/100g), iron (0.61mg/100g), vitamin C (44.3mg/100g), α-tocopherol (1.07mg/100g) and dietary fiber (2.15g/100g). The berries contained much more of those components than any other berries and fruits. Vitamin C was stable during frozen storage over a period of a year. Citric acid was the major organic acid, and the total amount of organic acids was 2.92g/100g. The average pH and weight of a berry were 2.77 and 0.9g, respectively. Positive correlations between ash and potassium, and ash and magnesium were recognized on dry matter bases.

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We discussed the differences among the lemon oils of California prepared by In-line and Sicily prepared by the three conventional methods, In-line, Sfumatrice and Pelatrice-method (C-I, S-I, S-S and S-P, respectively) in the previous paper. In this paper, we analyzed the components of oils after separation by elution chromatography and evaluated each flavor of fraction. The lemon oils were separated into two parts, hydrocarbon and oxygenated fraction on silica gel. Then oxygenated fraction was subjected to elution chromatography and separated to seven fractions. All fractions were subjected to GC-MS analysis and to flavor sensory evaluation. Some differences were observed among the components of the lemon oils. That is, the amounts of citronellal, neral, geranial, 1, 8-cineole in lemon oil cropped in Sicily were larger than that in California. This indicated that lemon oil in Sicily was more fresh than that in California. Among Sicilian oils, geranial, neral and 1, 8-cineole effect on flavor evaluation, that is, S-P is highest in fresh and next is S-S and last is S-I. C-I is inferior to S-I. In comparison with components among the four fraction-3 (these fractions obtain the highest score in lemon note) separated from oxygenated compounds fraction of the four lemon oils (C-I, S-I, S-S and S-P), large difference is observed in neral content (S-P is highest). On the contrary, geranial content shows just against this tendency (S-P is lowest). A flavor matrix of lemon beverage model prepared from oxygenated fraction separated from the four lemon oils is proposed. Comparing this flavor matrix with that of original lemon oil, it is obvious that hydrocarbon fraction also contributes lemon flavor boosting.

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Twenty vegetable juices were investigated for the scavenging abilities of the superoxide anion radical (O₂-) and their change during heat processing using xanthine-xanthine oxidase system (nitro blue tetrazolium (NBT) and luminescence methods). The fresh vegetable juices were cooked by five methods. All fresh vegetable juices had O₂- scavenging abilities measured by the NBT method. Furthermore, the juices of broccoli, cabbage, green pepper and leek showed the strongest abilities of a11. The abilities of the juices from carrot, tomato, onion and bean sprout decreased due to heating process, particularly boiling and microwave cooking. The juices of vegetable rich in chlorophylls had also the strongest abilities, except for cucumber, Japanese pumpkin and lettuce after heating. Considerable amounts of chlorophyll a remained in spinach after cooking, although its scavenging abilitywaslowerthanthatofβ-carotene and α-tocopherol. Fresh carrot juice showed the strong scavenging ability by NBT method, but it did not show the activity by luminescence method.

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"KABURAZUSHI"is a traditional fermented food in Kanazawa district, made of turnip and yellowtail. The sugar, organic acid and free amino acid composition and bacteria counts of KABURAZUSHI were investigated. The bacteria counts of Lactococciwere10³-10⁷/g, and that of both Lactococci and Lactobacilli increased to about 10⁶/g in 9 day. In all samples, the major sugar component was glucose. Sucrose was decreased during fermentation, and not detected in the final stage. The major organic acid components were acetic acid and formic acid in all samples. Lactic acid increased to about 10 times during fermentation. The total amounts of free amino acids were 231-535mg/100g. Sensory evaluations indicated that the sample has strong"umami"and has not so strong sweetness and sourness was preferred most.

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Southern blot hybridization was applied to differentiate between Japanese black cattle and the other four cattle breeds (Holstein, Aberdeen-Angus, Hereford and Murray Grey). The probes, P³²-labelled human DNA (DRB 1 and DQB 1) were hybridized with the bovine DNA fragments on nylon membranes. The restriction enzymes, which were optimized to differentiate between the breeds of cattle, by the preliminary experiment were Pvu II, Bgl II and Stu I. The bovine sample were digested with Pvu II and Stu I and hybridized to the HLA-DQB 1 probes. For the results, Japanese black cattle of Pvu II fragments hybridizing with the DQB 1 probe had the specific fragments of 7.6kb, 5.8kb, 5.0kb and 4.8kb. The other bovine breeds of Stu I fragments hybridizing with the DQB 1 probe had the specific fragments of 8.0kb and 6.0kb (Holstein), 5.0kb (Aberdeen-Angus), 13.0kb, 12.0kb, 5.2kb and 3.8kb (Hereford), 9.0kb and 1.8kb (Murray Grey) respectively. From the restriction fragment patterns of bovine DNA samples digested with Pvu II, Bgl II and Stu I followed by the hybridization with HLA-DRB 1 and DQB 1 were possible to discriminate between Japanese black cattle and the other four breeds.

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An Adiabatic Expansion Sterilizer in a moment is developed by using combination works between a taper steel valve and link-motion mechanism, which is able to run over 380000 MPa/s of decompression velocity at 200MPa. Mechanism of present high pressure sterilization on Bacillus stearothermophilus IFO 12550 spore was physical destruction of the spore coat by adiabatic expansion of water permeated through the spore coat under pressure. Water volume permeated through the spore coat under pressure is rate-determining on spore disintegration, which was influenced by temperature. Sterilization was promoted over 75°C. The spore of B. stearothermophilus IFO 12550 was almost ruptured at 100MPa. D value under 200MPa is 17min at 75°C, 11min at 85°C and 6min at 95°C, respectively, when B. stearothermophilus spore IFO 12550 (D₁₀₀°C values=3000min) are compressed for 20min. Spore coats are broken to brittle fracture exactly when balk strain velocity of water exceeds in 42.4/s/sec (at decompression of 200MPa).

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