We studied inhibitory effects of Sugar Cane Extracts (SCEs) on 4 types of chemically induced liver injury models using mice (carbon tetrachloride (CCl₄), CCl₄ with phenobarbital, α-naphthyl-isothiocyanate (ANIT) and D-galactosamine). Three types of the SCEs were prepared by different extraction methods. The Extract 1 and the Extract 2 were obtained by synthetic adsorbent resin column chromatography from sugar cane juice and distillation liquid of sugar cane juice, respectively. And the Extract 3 was obtained by the hot water extraction from bagasse. The SCEs (500mg/kg·day) were orally administrated, respectively for 5 consecutive days and any of chemical treatments was performed at 6 hours before the 5th administration. The SCEs effectively reduced both plasma GOT and GPT activities significantly cornpared with a positive control group in each model. The 4 models were induced by the different mechanisms, and the SCEs were prepared by the different methods, however, all of them were effective on all the models tested. These results suggest that sugar cane contains components which possess the potentiality reducing the several types of liver injuries though mechanisms of these effects, one of which is possibly an antioxidant effect (on the Extracts 1 and 3 which are supposed to contain polyphenols), are not known in detail (on the Extract 2 which is volatile liquid and supposed to contain phenolic compounds).

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The deodorizing activity of cacao nib and husk extracts on methyl mercaptan (CH₃SH) was measured by gas chromatograph. Cacao nib and husk were extracted with water, 50% and 100% Ethanol. Among these extracts, 50% ethanol extract of cacao husk showed the highest deodorizing activity against CH₃SH. The active components of cacao bean husk were considered to be a mixture of polyphenolic compounds, because of positive correlation with deodorizing activity and the polyphenol content of cacao husk extracts. The 50% ethanol extract of cacao bean husk was separated into six fractions (50E-1-6) by column chromatography with Diaion HP20. The fraction 50E-4 containing a large amount of polyphenols possessed higher deodorizing effect than sodium copper chlorophyllin. ¹³C-NMR analysis and gel permeation chromatography analysis showed that the main component of the fraction 50E-4 was a mixture of higher polymerized (-)-epicatechin. In the examination of deodorizing effect using procyanidin monomer to pentamer, the activity progressively increased with increasing the number of (-)-epicatechin unit.

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Antioxidative and antimicrobial activities, and flavonoid content were surveyed in the eight organically cultivated (OC) vegetables. The same varieties of vegetables generally cultivated (GC) using a chemical fertilizer harvested from nearby farm on the same day were used for comparison of the activities and chemical composition. In the study, OC vegetables, such as cabbage, spinach, broccoli, and Welsh onion were indicated to show more than 50% higher antioxidative activity compared to that of GC vegetables. OC Chinese cabbage showed higher antimicrobial activity against Salmonella, and OC cabbage and Japanese radish against Vibrio, than those observed in GC vegetables. LC/MS quantitative analysis revealed that at least two fiavonoids content were determined to be more than double (significant at 95% level in t-test) in Welsh onion, Qing-gen-cai, and spinach in comparison with those in GC vegetables.

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In order to evaluate the effect of lipid-oxidation products resulted from lipoxygenase (LOX) and autoxidation reactions on the sensory quality of tofu, particularly mouthfulness (richness), the contents of several components (protein, total lipids, free sugars, isofiavones, total carbonyl compounds, and malondialdehyde) and the sensory taste of tofu made from a normal or a LOX-deficient soybean cultivar by adding vegetable oils were investigated. The vegetable oils used were olive oil (OLO) containing 70.7% oleic acid, safflower oil (SO) containing 76.9% linoleic acid and perilla oil (PO) containing 62.5% linolenic acid. The tofus made from Fukuyutaka (normal cultivar) or Ichihime (LOX-deficient cultivar) by adding each vegetable oil were similar in their contents of protein, total lipids, free sugars and isoflavones. The total carbonyl compounds contents in the tofus of Fukuyutaka were much more than those of Ichihime. The tofu (PO-tofu) prepared by adding PO to Fukuyutaka or Ichihime indicated higher TBA value compared with those (OLO-tofu and SO-tofu) prepared by adding OLO or SO to each soybean cultivar. On the comparison of sensory taste among the tofus added different vegetable oils, the intensity of mouthfulness increased, from the lowest, in the order of OLO-tofu<SO-tofu<PO-tofu on each cultivar of Fukuyutaka and Ichihime. These results suggested that the intensity of mouthfulness was dependent on the total content of linoleic acid and linolenic acid, particularly the content of linolenic acid. On the comparison of sensory taste between the tofus of Fukuyutaka and Ichihime, the SO-tofu of Fukuyutaka was more mouthful than SO-tofu of Ichihime. Both PO-tofus of Fukuyutaka and Ichihime were mouthful. The panel judged that the tofus (SO-tofu and PO-tofu) of Fukuyutaka have desirable mouthfulness, while those (SO-tofu and PO-tofu) of Ichihime undesirable mouthfulness.
These results suggested that the lipid-oxidation products resulted from LOX reaction contributed to the desirable mouthfulness, while the lipid-autoxidation products to the undesirable mouthfulness.

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In order to visualize sugar content of a melon, the relationship between sugar content and absorption spectra was investigated using a near-infrared (NIR) spectrometer. The absorbance at 676 nm had a high inverse correlation with sugar content. A high-resolution cooled CCD imaging camera with the band-pass filter of 676nm was used to capture the spectral absorption image. The calibration method for converting the absorbance on the image into Brix sugar content was developed in accordance with NIR techniques. Applying this method to each pixel of the absorption image, a color distribution map of the sugar content was constructed. Quantitative analysis of sugar distribution for unripe, mature and fully mature melons was carried out. In addition, a special slicing device that can cut a melon in each 5mm thickness was developed in order to create a 3-D image of sugar content distribution.

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Aqueous solution of L-ascorbic acid (20-1000mg/100ml) was stored at 40-60°C for three months in the coexistence of sugars and sugar alcohols (15g/100ml). During the storage period, the total and oxidized vitamin C contents also with browning (an increase in the absorbance at 420nm) of the solution were measured. Change in the composition of sugars and sugar alcohols added to the solution caused by heating was also analyzed. The results obtained were as follows:
(1) During the heating storage, the total vitamin C gradually reduced. With increasing the vitamin C concentration and the volume of air in headspace of a glass-vessel, the reducing rate of vitamin C tended to decrease.
(2) The heating storage brought about, the browning of the vitamin C solution. There was a positive correlation between the reduction of vitamin C and the increase in the browning at the initial stage.
(3) The addition of 15% sugars or sugar alcohols to the vitamin C solution slightly suppressed the reduction rate of vitamin C. On the other hand, the browning was hardly affected by sugar alcohols, but largely enhanced by reducing sugars like as fructose.
(4) Under the conditions of the heating storage, all of the sugar alcohols, fructose, and glucose practically unchanged, whereas sucrose rapidly decomposed to the equal amount of fructose and glucose.
(5) When a portion of fructose was replaced by a sugar alcohol (such as maltitol), promotion of the browning caused by fructose was diminished.
These results indicated that the browning of vitamin C aqueous solution occurred presumably with the formation of the Maillard-type reaction product, and it was enhanced on addition of reducing sugar but suppressed by substitution for sugar alcohol.

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A new temperature control program was developed to improve the quality of natto. Oxygen concentration was also measured to decide quantitatively the relationship with quality of natto. Using the program A (MURAMATSU et al., 1995), 10³ cells/g of inoculation of three commercial natto starters gave satisfactory results. We devised five new temperature programs to improve the quality of natto, of which the best program required to set the temperature initially at 42°C, to rise it up to 47°C for 3 or 4 hours on the way and to decrease it to 5°C at the 20th hour (program 4). When the set temperature was raised up to 47°C, the internal temperature of natto raised 5°C higher than the set temperature. The flavor of the natto obtained by this program was weak and the viscosity was strong. Natto manufactured by Program 4 was more viscous than those manufactured by program A (constant at 40°C), and natto manufactured from Starter C was especially viscous. The gas chromatographic patterns of various samples of natto produced by 3 starters did not vary much. The same peaks were detected with regard to the volatile components of each natto sample, although the peak area of these peaks varied. The smaller sized soybean varieties, Akita and Shirome, which were bred for natto, were best for manufacturing natto by Program 4. Larger sized soybean, Suzuyutaka, which was bred for tofu, was better than other soybean varieties for manufacturing natto. The natto manufactured from Akita and Shirome had the flavor of so called "genuine" natto, but lacked soybean savor that was present in natto manufactured from Suzuyutaka.

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Since one of the natto flavor components, 3-methyl butanoate is a metabolite of leucine, two leucine-requiring mutants of elastase-producing Bacillus subtilis (natto) KFP 419 were obtained by ultra-violet irradiation to develop natto with weaker flavor. The natto manufactured with these mutants did not contain sticky materials at 41°C but turned to be viscous at 43°C on program A of the Automatic Natto Manufacturing lnstrument. The optimum growth temperature of KFP 419 and the mutants coincided with that for manufacturing good quality of natto. The effect of oxygen supply on the quality of natto was not clarified by an experiment using a respiramy cup at the bottom of which an air-permeable plastic laminated film was spreaded. As the odor of natto made by both mutants was weak, to characterize the natto, the volatile components of the head space gas of natto were analyzed by GLC. Although the odor of 3-methyl butanoate was smelled by sniffing at the retention time of this component, its peak was too small to determine quantitatively. It was suggested that the characteristics of the flavors of natto manufactured by the mutants were attributable to complicated quantitative ratio of many volatile components. The elastase activities of the natto of both mutants were lower than that of the parent strain when manufactured at 40°C, but were at the same level as the latter when manufactured at 43°C.

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Peeled and crushed potato (200g) treated at 100°C for 30min, rice koji (40g) and aqueous 35% (w/v) ethanol solution (100g) were used for making potato mirin, a wine-like sweet seasoning. Antioxidative activity of potato mirin obtained after incubation at 30°C for 45 days was examined with both Rodan ferric method (as linoleic acid peroxidation) and β-carotene bleaching method (as BHA equivalent). (1) Linoleic acid peroxidation in potato mirin (5% (v/v)), BHA (0.1% (w/v)) and commercial mirin (5% (w/v)) was 2%, 12% and 110%, respectively. Compared with commercial mirin, the antioxidative activity of potato mirin was very high. (2) BHA equivalent of rice koji, peeled and crushed potato and potato mirin (218.5g) was 14.3, 6.0 and 213.2mg, respectively, showing extremely high value in potato mirin. That is, it was indicated that the antioxidative activity of potato mirin was reinforced remarkably by incubation.

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The endosperm cell wall was prepared from several kinds of glutinous rice grains, and divided in pectin, hemicellulose, cellulose. The hydroxyproline of the each fraction was measured and compared with texture characteristic value of cooked glutinous rice. As the result, the hydroxyproline mainly existed for both fractions of hemicellulose and cellulose. There was a correlation between HYP contents in their fraction and hardness, adhesiveness of cooked glutinous rice. The property of the rice endosperm cell wall seemed to be one of the factors which affect the texture of cooked glutinous rice.

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Cultivar identification by the PCR method was investigated using 4 typical glutinous rice grains and rice cake as samples. (1) Two different DNA extraction methods, which were extractions from material rice grains by CTAB method and extraction from rice cakes by the "enzyme method", showed same results in the glutinous rice cultivar identification. (2) It was revealed that the cultivar identification by the PCR method can be used not only for rice grains and cooked rice but also for processed rice cake. (3) "Multiplex method", PCR using combination of several suitable STS primers, was shown to be useful to differentiate glutinous rice cultivars by small numbers of PCR and electrophoreses.

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