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Volume 38, Issue 1
Displaying 1-7 of 7 articles from this issue
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-Effect of Magnesium Concentration on Enzymatic Degradation-Akinobu MATSUNAGA, Tooru OOIZUMI, Atsushi YAMAMOTO, Ken-ichi KAWASAKI, ...1997 Volume 38 Issue 1 Pages 1-6
Published: February 05, 1997
Released on J-STAGE: March 01, 2010
JOURNAL FREE ACCESSThe effect of magnesium (Mg) concentration on the degradation of polyphosphates (PP) in salted meat paste (SMP) during the setting process has been investigated. Surimi was prepared from minced walleye pollack muscle by washing twice with a buffer solution (pH 7.5). The SMPs, which were mixtures of surimi, NaCl, tripolyphosphate (P3), pyrophosphate (P2) and various concentrations of Mg, were incubated at 20°C for 0-20hr. Amounts of P3 and P2 remaining in SMP were measured. While P3 was completely degraded within about 8hr, regardless of Mg concentration (3-13mmol/kg), P2 degradation was dependent on Mg concentration in SMP. P2 was hardly degraded in the presence of 3mmol/kg Mg for 20hr, but was completely degraded at 13mmol/kg Mg for 8hr.
The effect of Mg on pyrophosphatase (P2ase) and tripolyphosphatase (P3ase) activities has been investigated at various concentrations of P2 and P3. The relation between activity and Mg concentration was hyperbolic for P3ase and sigmoid for P2ase. Both P3ase and P2ase activities were saturated at Mg concentrations higher than the P3 and P2 concentrations. Moreover, P2ase activity decreased with increasing P2 concentration below 3mmol/kg Mg. It was presumed that these differences in Mg concentration dependence of P2ase and P3ase are relevant to the degradation rate of PP in SMP.
On the other hand, the gel strength of SMP was recognized to increase in the presence of Mg at a concentration sufficient to form Mg-PP complex. Therefore, it is suggested that increase of Mg concentration in SMP not only accelerates P2 degradation, but also enhances gel strength.View full abstractDownload PDF (1048K) -
Yukio TANAKA, Yoshimasa KONISHI, Yutaka TAKAGAKI1997 Volume 38 Issue 1 Pages 7-11
Published: February 05, 1997
Released on J-STAGE: March 01, 2010
JOURNAL FREE ACCESSThe effect of spices on immediate allergic reaction was evaluated using a newly developed assay method. Using rat basophilic leukemia cells (RBL-2H3) instead of the conventional method based on histamine release from mast cells, this method permits highly accurate mass screening since β-hexosaminidase is determined as the index of chemical mediator release and a good correlation exists between the amounts of β-hexosaminidase and histamine released from RBL-2H3 cells. Twenty-four spices were investigated for their effect on β-hexosaminidase release from RBL-2H3 cells stimulated with biotinylated IgE-avidin complex. Cinnamon, clove, Japanese pepper, garlic, bay leaves, oregano, thyme, sage and allspice showed release-inhibitory action. This inhibitory action was not caused by cell death. Thus, it appears that some spices exhibit antiallergic activity.View full abstractDownload PDF (959K) -
Kazuhiro FUJITA, Kanako ITO, Emiko ARAKI, Kenji TANNO, Mitsunori MURAY ...1997 Volume 38 Issue 1 Pages 12-15
Published: February 05, 1997
Released on J-STAGE: March 01, 2010
JOURNAL FREE ACCESSAn analytical method for residual oxytetracycline (OTC) in livestock and marine products was evaluated. OTC was extracted from a sample with McIlvaine buffer (pH 4.0) containing 0.01mol/L EDTA-2 Na. The extract was washed with hexane, followed by a Sep-Pak Plus PS2 cartridge clean-up procedure. OTC was determined by HPLC. The results obtained by HPLC were well correlated with those of a microbioassay method. The average recovery at the tolerance limit levels established by the Food Sanitation Law of Japan was 90.4% and the determination limits were 0.02ppm (muscle, seafood, milk), 0.04ppm (liver, kidney, egg) and 0.002ppm (fat).View full abstractDownload PDF (723K) -
Masahiro OKIHASHI, Hirotaka OBANA, Shinjiro HORI1997 Volume 38 Issue 1 Pages 16-21
Published: February 05, 1997
Released on J-STAGE: March 01, 2010
JOURNAL FREE ACCESSIn order to find a suitable mobile phase for gel permeation chromatography (GPC) without using dichloromethane, we have fractionated corn oil, spinach color, paprika color, fluvalinate and chinomethionat by GPC on two columns. The solvent mixtures used in this study were ethyl acetate-cyclohexane (1: 1), ethyl acetate-cyclohexane (3: 7) and acetone-cyclohexane (3: 7). When the pesticide fraction was identified as the possible maximum collection from fluvalinate to chinomethionat, corn oil and paprika color were practically excluded from the pesticide fraction, using a cyclohexane-rich eluent. Spinach color was 71% eliminated from the pesticide fraction with acetone-cyclohexane (3: 7) as the eluent. The results suggest that suitable mixtures for residual pesticide analysis would be acetone-cyclohexane (3: 7) and ethyl acetate-cyclohexane (3: 7), depending upon the column selection.View full abstractDownload PDF (844K) -
Jin SUZUKI, Chiyomi OKUMOTO, Yasutaka KATSUKI, Toshio TOMOMATSU, Yukih ...1997 Volume 38 Issue 1 Pages 22-26
Published: February 05, 1997
Released on J-STAGE: March 01, 2010
JOURNAL FREE ACCESSAn analytical method for residual sodium chlorite (NaClO2) on vegetables and eggs treated with NaClO2 was studied.
NaClO2 was extracted with water. The extract was cleaned up through as ODS cartridge and was chromatographed on a TSKgel IC-Anion-PWXL PEEK column with 1mmol/L borate buffer as the mobile phase. NaClO2 was detected by a UV detector set as 260nm.
Recoveries of NaClO2 were 90-100% at the level of 0.01g/L spiked in rinsing water from cabbage, carrot, green pepper, Japanese radish, cucumber, potato, lettuce, bean sprout and radish sprout, as well as cut vegetables and hen's eggs. Water-rinsing of vegetables was effective to remove residual NaClO2. The detection limit of NaClO2 in vegetables and eggs was 1mg/kg.View full abstractDownload PDF (869K) -
Yoko KAWAMURA, Makiko MIURA, Takiko SUGITA, Takashi YAMADA1997 Volume 38 Issue 1 Pages 27-33
Published: February 05, 1997
Released on J-STAGE: March 01, 2010
JOURNAL FREE ACCESSThe residue and release of 28 kinds of antioxidants and ultraviolet stabilizers in polyethylene products were investigated. The samples included a total of 36 kinds of kitchenware, e. g., bags, wrapping films, sauce bottles and a chopping board, and a total of 16 food-packages, e. g., bags, cases, nets and a tube. They were analyzed using the simultaneous determination method with HPLC. Most samples contained 1-3 antioxidants, mainly Irganox 1076, Irgafos 168, BHT and Irganox 1010. The residue level was about 50-1, 000μg/g. The migration test was carried out using high-residue samples. No additives were released into water, 20% ethanol or 4% acetic acid at 60°C after 30min, though some additives were released into n-heptane at 25°C after 60min.View full abstractDownload PDF (1030K) -
Takashige SHIMIZU, Teruyo MUROI, Takahito ICHI, Mikio NAKAMURA, Kunito ...1997 Volume 38 Issue 1 Pages 34-38
Published: February 05, 1997
Released on J-STAGE: March 01, 2010
JOURNAL FREE ACCESSA method for analysis of red cabbage colors in processed foods has been developed using high performance liquid chromatography with photodiode array detection-mass spectrophotometry (PDA-LC-MS). The beverages were simply diluted with water. The red cabbage colors were extracted from the jellies with hot water, cleaned up using a C18 cartridge and injected into the PDA-LC-MS system to carry out determination and identification simultaneously. The recoveries of red cabbage colors from laboratory-prepared beverage and jelly were 90.0 and 55.5%, respectively. The detection limit of the total colors was 5μg/g calculated as cyanidin 3-glucoside. Processed beverage and jelly were analyzed by this method, and the red cabbage colors in the samples were identified and determined successfully.View full abstractDownload PDF (880K)
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