Food Science and Technology Research
Online ISSN : 1881-3984
Print ISSN : 1344-6606
ISSN-L : 1344-6606
Volume 6, Issue 4
Displaying 1-22 of 22 articles from this issue
Review
  • Tomoyuki KATSUBE-TANAKA, Shigeru UTSUMI
    2000 Volume 6 Issue 4 Pages 241-247
    Published: 2000
    Released on J-STAGE: January 30, 2007
    JOURNAL FREE ACCESS
    Plant transformation techniques were first developed as analytical tools of basic research on the regulational mechanism of gene expression and gene function. Presently, they are also used as applied tools to develop valuable crops. Practical methods for plant transformation to date include Agrobacterium mediated, electroporation, and particle gun methods, all of which have positive and negative attributes. Most of the GMO developed so far (the first generation of GMO) have such features as improved productivity or environmental and grower-friendly advantages, so that they are beneficial mainly to growers. It is, however, predicted that the second generation of GMO is likely to be placed at the center of future development of GMO. These are more related to consumers’ interests, which include benefits in health promotion and palatability for developed countries and nutritiousness and peroral immunization (vaccine) functions for developing countries.
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  • Shyam Narayan JHA, Takahisa MATSUOKA
    2000 Volume 6 Issue 4 Pages 248-251
    Published: 2000
    Released on J-STAGE: January 30, 2007
    JOURNAL FREE ACCESS
    Consumers are now more conscious about quality and source of their foods. Attempts made to determine the quality of food materials are numerous, but most of them are destructive in nature. In recent years, nondestructive methods of quality evaluation have gained momentum and a considerable attempts have been made to develop them. This paper reviews application of these non-destructive methods: magnetic resonance imaging, x-ray computer tomography, near infrared spectroscopy and a few other important techniques for determination of different quality attributes with emphasis on fruits and vegetables, and discusses their pros and cons for practical exploitation.
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Technical papers
  • Jie Yu CHEN, Keiichi ISOBE, Han ZHANG, Ryuji MATSUNAGA
    2000 Volume 6 Issue 4 Pages 284-287
    Published: 2000
    Released on J-STAGE: January 30, 2007
    JOURNAL FREE ACCESS
    Experimental drying curves of udon noodles in an air temperature (dry bulb) range of 15 to 65°C and a relative humidity range of 60 to 80% were evaluated to develop an appropriate mathematical model to predict the moisture content of udon noodles at any time during the air-drying process. Three simple mathematical equations were used to try to fit these curves, and it was found that Page’s equation had the best fittings for the experimental drying data by doing comparative analysis of the coefficients of determination and standard deviations. Page’s equation was finally selected to describe the drying curves of these noodles and the dependency of the drying parameters (e.g., slope and intercept) on air temperature and relative humidity was investigated. A generalized model based on Page’s equation with drying parameter K (function of air temperature and relative humidity) and n (constant) provided a suitable description of hot-air drying behavior of udon noodles.
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  • Yutaka KITAMURA, Kiyohiko TOYODA, Bosoon PARK
    2000 Volume 6 Issue 4 Pages 310-313
    Published: 2000
    Released on J-STAGE: January 30, 2007
    JOURNAL FREE ACCESS
    The relationship between electric impedance spectroscopy (EIS) parameters and the conventional parameters of pH, acidity and hardness was discussed to evaluate the technique’s applicability as an on-line monitoring system of food processing automation, specifically yogurt processing. To determine pH, acidity and hardness, impedance (Z) obtained with an EIS measurement system was used during the yogurt processing at different temperatures. Time course curves for both pH and acidity had only gentle slopes showing the progress of lactic fermentation; however the time course for hardness had bending points indicating the start of coagulation. Also, these bending points were found at the time course for the Z ratio obtained as 100 kHz Z divided by 0.1 kHz Z. The relationships between Z ratio and both acidity and hardness have respective linear functions and the calculated acidity and hardness using the Z ratios showed agreement with those measured in the yogurt processed from the same materials. The EIS technique is applicable for monitoring yogurt processing and is more sanitary and non-destructive method than the conventional method.
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Original papers
  • Shuji ADACHI, Ryuichi MATSUNO
    2000 Volume 6 Issue 4 Pages 330-334
    Published: 2000
    Released on J-STAGE: January 30, 2007
    JOURNAL FREE ACCESS
    The apparent distribution coefficients, Kapp, of glucose and fructose onto cation-exchange resins in calcium-ion form with different divinylbenzene (DVB) contents were observed over a wide concentration ranges. Irrespective of the DVB content of the resin, the Kapp value of glucose was larger with an increase in the glucose concentration, while the Kapp value of fructose was smaller at higher fructose concentrations. A method for estimating the binding constant of fructose to the calcium-ion, BFru, was proposed under the assumption that the constant of glucose could be approximated as zero, and the BFru value was evaluated as 0.66 l/mol. The Kapp values of mannose onto a resin with a DVB content of 4% were also measured at various solute concentrations, and the BMan value was estimated to be 0.31 l/mol.
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  • Xiang-Dong LIU, Takeshi FURUTA, Hidefumi YOSHII, Pekka LINKO
    2000 Volume 6 Issue 4 Pages 335-339
    Published: 2000
    Released on J-STAGE: January 30, 2007
    JOURNAL FREE ACCESS
    The prevention of the loss of flavor compounds during spray drying is one of the most important engineering techniques to obtain high quality powdery food products. In the present study, a droplet drying technique was used to evaluate the mechanism of the loss of hydrophobic liquid flavors from a droplet containing flavor emulsions in an aqueous mixture solution of gum arabic and maltodextrin. The effects of type of flavor, air temperature, the initial concentration of carrier solids and the stability of the emulsion on the retention of different kinds of flavors were investigated. The retention of flavor was markedly dependent on the type of flavor and the stability of emulsion, and retention could be correlated well with emulsion stability. A simple mathematical model of the loss of emulsified flavor during drying was proposed, based on a breakdown hypothesis of the emulsion droplet.
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Technical papers
  • Motoko UEDA, Katsuaki SASAKI, Naoki UTSUNOMIYA, Kazunari INABA, Yoshih ...
    2000 Volume 6 Issue 4 Pages 299-305
    Published: 2000
    Released on J-STAGE: January 30, 2007
    JOURNAL FREE ACCESS
    The changes in physical and chemical properties during maturation of ‘Irwin’ mango fruit were examined. The fruit used in this experiment was cultured in a plastic greenhouse {temperature: winter, min. 5°C (room) and 13°C (soil); summer, max. 39°C (room) and 30°C (soil)}, and harvested approximately at 10 (Sample I), 13 (Sample II), 16 (Sample III) and 19 (Sample IV) weeks after flowering, 1995. The weight and size of the fruit, total soluble solids, respiratory rate, and Hunter L and a values of the fruit surface increased during maturation. These increases were remarkable in Sample IV. However, the flesh firmness decreased gradually as the fruit matured. Citric acid was more abundant than malic acid, and the former decreased gradually in Sample, IV while the latter was nearly constant. Of free sugars, fructose and sucrose increased during maturation, and the latter dramatically increased in Sample IV. Thus, fructose, which was the predominant free sugar in Sample I, was replaced by sucrose in Sample IV. Furthermore, AIS (alcohol insoluble solid), starch and pectin increased and attained a maximum in Sample III but they decreased to a minimum in Sample IV. Amylase activities increased roughly in line with fruit maturation, reaching a maximum in Sample IV. It may be quite logical to consider that there are similarities in the patterns of change in flesh firmness, respiratory rate, organic acid and sugar content during fruit maturation without considering distinctions of cultivar, conditions or cultivation environment.
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  • Toshiyuki IBARAKI, Toshinao ISHII, Hironobu IKEDA, Emi IKEMATSU, Takeo ...
    2000 Volume 6 Issue 4 Pages 340-343
    Published: 2000
    Released on J-STAGE: January 30, 2007
    JOURNAL FREE ACCESS
    A theoretical model of the atmosphere within polymeric film and shipping containers was developed and validated by experiments with or without Welsh onion (Allium fistulosum L.). There were three processes in the model: respiration of fresh vegetables, permeability of gas in polymeric film and permeability of gas in the shipping container. The respiration rate of Welsh onion was expressed in a multiple regression equation. When empty packages were used, changes in carbon dioxide (CO2) and oxygen (O2) concentrations inside the unperforated polypropylene (OPP) film packaging and expanded polystyrene (EPS) containers agreed very well with the simulated data. These results indicate the suitability of the proposed model. Changes in CO2 and O2 concentrations in the EPS container were approximated when Welsh onion was placed in the film package. The predicted CO2 and O2 concentrations in the OPP film differed slightly from the experimental data obtained with a maximum of 1.5% and 1.2%, respectively, but gas correlated significantly with the model. Therefore, the simulation model may be useful for fresh vegetables wrapped with polymeric film and then encased in shipping containers.
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Original papers
  • Eiko ARAI, Tomio ITANI
    2000 Volume 6 Issue 4 Pages 252-256
    Published: 2000
    Released on J-STAGE: January 30, 2007
    JOURNAL FREE ACCESS
    In order to clarify the effects of early harvesting of rice grains on the taste characteristics of cooked rice, especially on the taste items of “sweetness” and “deliciousness,” we compared “early-harvest” rice which was harvested 10 days before the ordinary harvest time and “ordinary-harvest” rice which was harvested at the usual time. From the results of sensory tests, the cooked early-harvest rice was evaluated as being sweeter and more delicious than the cooked ordinary-harvest rice. The greater sweetness in the former rice was primarily due to the formation of glucose, maltose and maltoligosaccharides from starch, probably by starch degradation enzymes during soaking and/or cooking. The cooked early-harvest rice also contained more L-glutamic acid than the cooked ordinary-harvest rice. From these results, it was concluded that when rice is harvested 10 days before the ordinary time of harvesting, the cooked rice will be sweeter and more delicious.
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  • Adrian BERISHA, Yasushi ENDO, Kenshiro FUJIMOTO
    2000 Volume 6 Issue 4 Pages 257-262
    Published: 2000
    Released on J-STAGE: January 30, 2007
    JOURNAL FREE ACCESS
    Solutions of myoglobin from the heart of a horse were heated at various temperatures to assess the effect of heating temperature on the prooxidant and hydroperoxide decomposition activity of myoglobin. The solutions of the heated myoglobin were incubated with linoleic acid in various systems and the prooxidant activity was evaluated by measuring the absorbance at 234 nm and thiobarbituric acid (TBA) value. H2O2 was added to the reaction mixture to activate the myoglobin. To observe the lipid hydroperoxide decomposition activity of the heated myoglobin, the heat-denatured myoglobin was incubated with oxidized linoleic acid and the residual hydroperoxides were assessed fluorometrically. Both the absorbance at 234 nm and TBA values gave similar results and the incubation of heated myoglobin with linoleic acid resulted in a rather weak prooxidant activity regardless of the heating temperature. The supplementation of H2O2 activated myoglobin, whose activity was greatest when heated at 74°C, decreased when heated at 100°C. As a model of pre-cooked frozen foods, a part of the heated myoglobin solution was frozen and reheated. The prooxidant activity of the reheated myoglobin was similar and greatest by heating at 74°C, but when heated at 100°C it was less prominent than that of the control (unheated). The lipid hydroperoxide-decomposition activity of the heat-denatured myoglobin (heated or reheated under the same conditions) showed a slight alteration up to 74°C, however, heating at 100°C significantly lowered this activity.
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  • Takashi NAKAE, Takashi KOMETANI, Takahisa NISHIMURA, Hiroshi TAKII, Sh ...
    2000 Volume 6 Issue 4 Pages 263-268
    Published: 2000
    Released on J-STAGE: January 30, 2007
    JOURNAL FREE ACCESS
    Monogalactosyldiacylglycerol (MGDG), digalactosyldiacylglycerol (DGDG) and trigalactosyldiacylglycerol (TGDG) were extracted from pumpkin, then hydrolyzed to the corresponding galactosylmonoacylglycerols by 1, 3-specific lipase from Rhizopus arrhizus; MGDG was then hydrolyzed to diacylglycerol (DG) by β-galactosidase from Aspergillus oryzae. The kinetics of polymorphic transformation on cocoa butter and the effect caused by the addition of these seven glyceroglycolipids were investigated. Each glyceroglycolipid could be incorporated at the level of 5% into the cocoa butter without changing the crystal lattice. The polymorphic transformation on cocoa butter was induced by continuous temperature cycling between 32 and 20°C at 12 h intervals and monitored with a differential scanning calorimeter. The result indicated that MGDG, DGDG, TGDG and DG significantly retarded the polymorphic transformation from Form V to VI of cocoa butter compared to the control, while the other glyceroglycolipids had no effect. The addition of MGDG was the most effective. These results indicate that the number of the acyl chain and galactose of glyceroglycolipid strongly influence the polymorphic transformation of cocoa butter.
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  • Takashi NAKAE, Takashi KOMETANI, Takahisa NISHIMURA, Hiroshi TAKII, Sh ...
    2000 Volume 6 Issue 4 Pages 269-274
    Published: 2000
    Released on J-STAGE: January 30, 2007
    JOURNAL FREE ACCESS
    We earlier reported that glyceroglycolipid extracted from pumpkin significantly retarded the polymorphic transformation from Form V to VI of cocoa butter. We therefore investigated the effects of adding glyceroglycolipid on the fat bloom stability in dark and milk chocolates. Glycolipid fraction containing glyceroglycolipid was extracted with ethanol from pumpkin purée and partially purified on column chromatography. The apparent viscosity of dark and milk chocolates with the addition of the gained glycolipid fraction instead of lecithin significantly decreased up to 0.2% (w/w) according to a rotational viscometer at 45°C, and then decreased slightly at concentrations above that. The glycolipid fraction was then added to dark and milk chocolates up to 2% in place of lecithin. Each chocolate sample was evaluated for fat bloom resistance through two thermo-cycle tests given at an interval of 12 h between 30°C and 20°C, and between 32°C and 20°C. The accelerated tests indicated that the glycolipid fraction inhibited fat bloom compared to the control (0.4% lecithin). In dark and milk chocolates with the addition of 2.0% glycolipid fraction the polymorphic transformation from Form V to VI of cocoa butter was significantly retarded when measured by a differential scanning calorimeter. On the basis of these results, the quality of chocolate can be improved more effectively using the glycolipid fraction.
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  • Takashi YOKOTA, Hisanori TANI, Hifumi OHISHI, Tatsuo OGURO, Kenji WATA ...
    2000 Volume 6 Issue 4 Pages 275-279
    Published: 2000
    Released on J-STAGE: January 30, 2007
    JOURNAL FREE ACCESS
    The mechanism of antitumor activities in hen egg white ovomucin (OVM) was analyzed by examining the interaction between the 120 kDa fragment (a highly glycosylated fragment in β-subunit from the pronase-treated OVM) and basic fibroblast growth factor receptor (bFGFR). The 120 kDa fragment, which was transblotted onto a polyvinylidene difluoride membrane after SDS-polyacrylamide gel electrophoresis, was found to interact with bFGFR. The interaction was detected by Western blotting method with mouse anti-FGFR IgM. When sarcoma-180 (SR-180) cells were cultured on addition of the 120 kDa fragment, they were observed to be in the necrotic state by transmission electron microscopy, and the 120 kDa fragment was seen to be dispersed on the cell surface by light and transmission electron microscopic observations with the immunocytochemical staining method. The growth of SR-180 cell in the presence of bFGF was reduced with increase in the amount of 120 kDa fragment added. Thus, it was found that the 120 kDa fragment interacted with SR-180 cells through bFGFR and affected them.
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  • Masahiro SASAKI, Hideyuki YAMADA, Norihisa KATO
    2000 Volume 6 Issue 4 Pages 280-283
    Published: 2000
    Released on J-STAGE: January 30, 2007
    JOURNAL FREE ACCESS
    In this study we found that dietary supplementation of 4% of a silk protein, sericin, to a 20% casein diet significantly reduced apparent protein digestibility in rats compared to a 24% casein diet, and that the pattern of amino acid composition of feces from the rats fed the sericin-supplemented diet was similar to that of the amino acid composition of sericin; the pattern of amino acid composition of feces from rats fed the control (casein) diet was different from that of the amino acid composition of casein. In vitro experiments with pepsin and pancreatin also showed that the digestibility of sericin was markedly lower than that of casein. We further examined the possibility that consumption of sericin suppresses constipation because of its low digestibility along with high water-holding capacity. The results indicated that consumption of the 4% sericin supplemented diet suppressed atropine-induced constipation in rats. These results suggest that a resistant protein, sericin could represent a useful agent for the treatment of constipation.
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  • Motoi TAMURA, Hiramitsu SUZUKI, Kazuki SHINOHARA
    2000 Volume 6 Issue 4 Pages 291-293
    Published: 2000
    Released on J-STAGE: January 30, 2007
    JOURNAL FREE ACCESS
    The effects of intestinal microflora on the bioavailability of dietary quercetin in adult mice were studied. The control group was given a casein diet and water ad libitum. The antibiotics-treated group was given a casein diet and water that contained penicillin and streptomycin ad libitum. Fecal beta-glucuronidase activity was significantly greater in the control mice than in the antibiotics-treated mice. The concentrations of quercetin and isorhamnetin, after deconjugation of plasma quercetin metabolites, were significantly greater in the antibiotics-treated mice. The cecal pools of quercetin in the antibiotics-treated mice were significantly greater than those in the control mice. In untreated mice, it may be necessary to reduce the scission of quercetin and quercetin metabolites and greater beta-glucuronidase activity of the microflora might be needed to maintain a higher concentration of plasma quercetin metabolites.
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  • Tri Agus SISWOYO, Narumi MUKOYAMA, Naofumi MORITA
    2000 Volume 6 Issue 4 Pages 294-298
    Published: 2000
    Released on J-STAGE: January 30, 2007
    JOURNAL FREE ACCESS
    The effects of polyunsaturated phospholipids on changes in the thermal and physical properties of starch systems during mixing, baking and storage were studied. In the presence of phospholipids (PLs) or polyunsaturated fatty acid-containing PLs (PUFA-PLs), the viscoelastic properties of starch dough, such as stress, modulus of elasticity and viscosity coefficient were decreased, and the gelatinization enthalpy (Δhg) of dough also decreased slightly, but the starch-lipid complexes (Δhs-l) of dough and bread increased distinctly. Twenty-one days after its storage, the retrogradation rate (k) that was estimated by the change of re-gelatinization enthalpy (Δht) of starch containing PLs or PUFA-PLs, was slowed by a factor of 1.98 or 3.28 for dough; and 1.60 or 2.07 for bread, respectively, when compared with that of the control. The changes in retrogradation value of starch in bread seemed to correlate with the retrogradation value of starch in dough in differential scanning calorimetric data (r2=0.93). These changes in thermal and physical properties of dough and bread appeared to be caused by the formation of complexes between starch and the PLs.
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  • Natsumi YAMANAKA, Noriko OGAWA, Toru TAKAHASHI, Yuko MAKI, Takashi SAK ...
    2000 Volume 6 Issue 4 Pages 306-309
    Published: 2000
    Released on J-STAGE: January 30, 2007
    JOURNAL FREE ACCESS
    The absorption of glucose in rats was investigated to elucidate the effect of ingesting the viscous exudate of mekabu on digestive absorption. A solution containing 10% dried viscous exudate of mekabu and 10% glucose was administered orally to rats. Changes in blood sugar levels were then measured as well as retention time of the contents in the stomach and small intestine using rats which had undergone surgery to connect the end of the ileum with the distal colon. It was found that the maximum blood sugar levels tended to be lower in the rats which had received the feed with viscous exudate than in those in a control group which had received the solution containing glucose only; this suggested that the ingestion of mekabu viscous exudate together with glucose suppressed the maximum blood sugar level. The retention time in the stomach and small intestine was longer in the group administered feed containing viscous exudate than in the control group. Movement of the contents from the stomach to the small intestine was delayed, which is presumed to be the cause of the suppressed rise in blood sugar level. The viscosity of viscous exudate samples prepared at 10°C and 80°C differed, and we also investigated whether or not this difference affected glucose absorption. Rats given the feed containing the viscous exudate prepared at 80°C, which had a higher viscosity, had lower maximum blood sugar levels than those ingesting the feed containing 10°C exudate. The retention time of the digestive tract contents was also longer, and the fecal weight and sugar amount in feces tended to be greater.
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  • Toshiya TODA, Akane SAKAMOTO, Tsutomu TAKAYANAGI, Koki YOKOTSUKA
    2000 Volume 6 Issue 4 Pages 314-319
    Published: 2000
    Released on J-STAGE: January 30, 2007
    JOURNAL FREE ACCESS
    We evaluated the concentration and distribution of isoflavones in a total of 50 samples of soybean foods consumed daily in Japan by high-performance liquid chromatography (HPLC). A hierarchical cluster analysis using the measured isoflavone distribution classified these foods into 6 clusters. Experiments of heat processing representing standard commercial production processes of the foods clarified that each cluster was characterized by the effects of the heating method and temperature. Tofu, which is produced under mild heating conditions, showed similar isoflavone distribution to raw soybeans, having the highest proportion of 6″-O-malonyl-β-glucosides to total isoflavones, while soymilk, yuba, cooked soybean, and natto which are produced by comparatively stronger heat, showed a lower proportion of 6″-O-malonyl-β-glucosides and higher non-acylated-β-glucosides. In the production of kinako by roasting, the proportion of 6″-O-acetyl-β-glucosides, generated by decarboxylation of 6″-O-malonyl-β-glucosides, increased. Miso and soy sauce had an increased proportion of aglycons due to a lengthy fermentation period. Abura-age which is produced by frying tofu showed lower 6″-O-malonyl-β-glucosides than tofu, and higher 6″-O-acetyl-β-glucosides.
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  • Kouhei MIZUNO, Daisuke FUKUDA, Miho KAKIHARA, Mamiko KOHNO, Tran Lien ...
    2000 Volume 6 Issue 4 Pages 324-329
    Published: 2000
    Released on J-STAGE: January 30, 2007
    JOURNAL FREE ACCESS
    To investigate the possibility of applying staphylococcal catalase to eliminate H2O2 in lactic acid fermentation, an intracellular catalase from Staphylococcus warneri ISK-1 which exhibited high catalase activity was purified to homogeneity in a six-step purification procedure. The subunit molecular mass of the purified enzyme determined under denaturing conditions was 64,000. The absorption spectrum of the catalase showed a soret band at 406 nm, indicating that the enzyme is a heme protein. Km and Vmax of the catalase for H2O2 were 59 mM and 42,700 U/mg, respectively. The catalase showed a broad optimum pH (5.5–9.5) and stability to organic solvents. We cloned a catalase gene from S. warneri ISK-1 genome. Nucleotide sequence analysis of a 2.2-kb DNA fragment revealed an open reading frame of 1515 bp, called katA, encoding a protein of 504 amino acid residues. The predicted amino acid sequence showed a high homology with other typical catalases. No similarities to bacterial catalase-peroxidase type enzymes were found.
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  • Mie TSURUTANI, Masatsune MURATA, Seiichi HOMMA
    2000 Volume 6 Issue 4 Pages 344-347
    Published: 2000
    Released on J-STAGE: January 30, 2007
    JOURNAL FREE ACCESS
    When Japanese pear and apple are cut, the section of Japanese pear does not turn brown as readily as apple, although both fruits belong to the same family. Here, the enzymatic browning of the two fruits is compared. The activity of polyphenol oxidase (PPO) of Japanese pear was higher than that of apple. The PPO of Japanese pear existed uniformly throughout the fruit, while the PPO of apple was localized around the core. The content of chlorogenic acid, (+)-catechin, and (-)-epicatechin in Japanese pear was much lower than in apple. When these polyphenols were added to Japanese pear juice, the juice turned as strong a brown color as apple juice. Therefore, the reason why Japanese pear does not turn brown as easily as apple is that the amount of substrate of PPO in the former is much less.
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Notes
  • Toshiro SATO, Yutaka OHTANI, Yohoko YAMADA, Kohnosuke YAMAKAWA, Masami ...
    2000 Volume 6 Issue 4 Pages 288-290
    Published: 2000
    Released on J-STAGE: January 30, 2007
    JOURNAL FREE ACCESS
    Fractures of the lower limbs due to fatigue often occur in female long-distance runners. We examined the effect of simultaneous supplementation of 1.35 mg/day of vitamin K2 (MK-7MK-6) and 72 mg/day of soybean isoflavones for 30 days on bone metabolism in these athletes. Despite the daily intake of 200–400 μg of vitamin K, the vitamin was found to be subclinically deficient in athletes on the basis of γ-carboxyglutamic acid formation of osteocalcin, because supplementation of 1.35 mg/day of vitamin K2 markedly decreased serum undercarboxylated osteocalcin level by 81%. This suggests that 200 μg/day of vitamin K was not sufficient for γ-carboxylation of osteocalcin. Therefore, supplementation of vitamin K and soybean isoflavones may help reduce the risk of bone fracture in female long-distance runners.
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  • Takashi NAKAE, Takashi KOMETANI, Takahisa NISHIMURA, Hiroshi TAKII, Sh ...
    2000 Volume 6 Issue 4 Pages 320-323
    Published: 2000
    Released on J-STAGE: January 30, 2007
    JOURNAL FREE ACCESS
    Monogalactosyldiacylglycerol (MGDG), digalactosyldiacylglycerol (DGDG) and trigalactosyldiacylglycerol (TGDG) were prepared from various natural materials. In all glyceroglycolipids, linoleic acid, linolenic acid, palmitic acid, oleic acid and stearic acid were the major components. The kinetics of polymorphic transformation on cocoa butter and the effect caused by the presence of the glyceroglycolipids prepared from carrot, corn, wheat flour and Chlorella pyrenoidosa were investigated. Each glyceroglycolipid can be incorporated at the level of 5% within the cocoa butter without changing the crystal lattice. The polymorphic transformation on cocoa butter was induced by continuous temperature cycling between 32 and 20°C at 12 h intervals and monitored with a differential scanning calorimeter. The test results indicated that MGDG and DGDG significantly retarded the polymorphic transformation from Form V to VI on cocoa butter compared with the control, with the addition of MGDG being the most effective. These results indicate that MGDG and DGDG extracted from various natural materials are effective in retarding the polymorphic transformation of cocoa butter.
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