Food Science and Technology Research
Online ISSN : 1881-3984
Print ISSN : 1344-6606
ISSN-L : 1344-6606
22 巻, 6 号
選択された号の論文の16件中1~16を表示しています
Food Technology and Engineering
Original papers
  • Sinan Uzunlu, Işıl Var
    2016 年22 巻6 号 p. 727-732
    発行日: 2016年
    公開日: 2016/12/28
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    Mantı, the traditional Turkish food, was subjected to modified atmosphere packaging (MAP) to extend its refrigerated storage time. Beef, which is one of the main raw ingredients in mantı, is a highly perishable product. Therefore, it is essential that the microbiological effects of this product be analysed. The microbiological qualities of each mantı package were assessed by analysing raw mantı samples to determine the number of Lactobacillus spp. they contained, as well as the total anaerobic mesophilic microorganisms, the amounts of Staphylococcus spp., yeast and mould, the coliforms, Escherichia coli, Salmonella spp. and Clostridium perfringens and the total aerobic psychrophilic microorganisms. Salmonella spp. and C. perfringens were not detected in the raw materials or the packed samples, but the Lactobacillus spp. and total anaerobic mesophilic microorganism counts increased during cold storage. Growth of Enterobacteriaceae species in a modified atmosphere during the period in which the mantı is being stored must also be taken into account. The compositions of the MAP samples lasted for the maximum storage time of 126 days as opposed to 20 days in normal atmospheric packaging. In conclusion, more than 40% carbon dioxide (CO2) with nitrogen (N2) should be used in the mantı process.

  • Motohiro Shima, Hiroto Sakashita
    2016 年22 巻6 号 p. 733-738
    発行日: 2016年
    公開日: 2016/12/28
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    The concentration of conjugated diene structures produced by the oxidation of glyceryl trilinoleate was measured spectrophotometrically. The test lipid was held at 5, 30, 40 and 50°C in air. The concentration was estimated using the molar absorption coefficient of conjugated methyl linoleate. The results showed that the concentration of conjugated diene structures was rapidly increased at higher temperatures. Rate constants were determined from the experimental results according to a chemical reaction model and its kinetic equations for the lipid oxidation process. Transient changes in the concentration of conjugated diene structures as calculated from the rate constant explained the experimental results well. The Arrhenius activation energy was 155 kJ/mol.

  • Chisako Kambara, Takashi Kobayashi, Shuji Adachi
    2016 年22 巻6 号 p. 739-742
    発行日: 2016年
    公開日: 2016/12/28
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    d-glucuronic acid (GlcA) and d-glucuronolactone (GlcL) were treated with subcritical aqueous ethanol in the range of 0% to 80% (w/w) at 180°C in order to examine the effect of ethanol on the interconversion between GlcA and GlcL. When GlcA was treated at higher ethanol concentrations, less GlcA disappeared and more GlcL was formed compared to treatments at lower ethanol concentrations. For comparison, in the treatment of GlcL at higher ethanol concentrations, disappearance of GlcL was slower and less GlcA was formed. The degradation and interconversion of GlcA and GlcL were kinetically analyzed under the assumptions of first-order kinetics in order to evaluate the rate constants for each process. The rate constants were smaller at higher ethanol concentrations. This was particularly manifested in the significantly low rate constants observed at ethanol concentrations higher than 60%. The treatments of GlcA and GlcL were also examined at 200°C, and the effect of ethanol at 200°C was similar to that at 180°C.

Technical papers
  • Kazuki Iwashita, Motoki Sumida, Kazuya Shirota, Kentaro Shiraki
    2016 年22 巻6 号 p. 743-749
    発行日: 2016年
    公開日: 2016/12/28
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    Surimi wash-water (SWW) contains a high concentration of protein resulting in a negative environmental impact and high disposal costs. Isoelectric point precipitation has been used for protein recovery from SWW. Here, we show an improved protein recovery method combining pH shift and heat treatment for Alaska pollock SWW. In a laboratory-scale experiment, a pH shift from neutral to pH 5 precipitated 63% of the SWW protein and subsequent heat treatment at 60°C precipitated almost all of the remaining protein. In a factory-scale experiment, the optimized pH shift and heat treatment yielded a 21% protein pellet with a 79% moisture content. The SWW protein gel thus obtained showed suitable quality as a surimi product as determined by the similar whiteness and strength as gel prepared from low-grade surimi. The optimized method combining pH shift with heat treatment improves the protein yield from SWW and prevents environmental pollution.

  • Yao Lin, Jiang Yanhua, Li Qingjiao, Sui Zhe, Wang Lianzhu, Zhai Yuxiu
    2016 年22 巻6 号 p. 751-757
    発行日: 2016年
    公開日: 2016/12/28
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    DNA extraction is critical for seafood authentication based on DNA techniques. In this study, eight extraction methods, including commercial kit, from three types of seafood (quick frozen, roasted, and canned products) were compared in terms of DNA yield and purity. The quantity and quality of extracted DNA were evaluated using the ratio A260/A280. Quality was also evaluated by two pairs of primers that could amplify two different sizes of DNA fragments respectively. For quick frozen samples, the results showed that the top three methods for DNA yield were the SDS method, TIANGEN GMO food DNA Extraction Kit, and TIANamp Marine Animals DNA Kit. For roasted samples, the top two methods for DNA yield were the SDS and improved CTAB methods. For canned samples, the top two methods for DNA yield were the SDS and phenol/chloroform/isoamylic alcohol methods. The differences between these aforementioned methods and the remaining methods were highly significant (P < 0.01). The DNA extracted from roasted and canned seafood could not amplify the 650 bp but amplified the 358 bp target fragment. This study determined the proper DNA extraction method for three types of seafood to facilitate seafood authentication.

  • Ling Zhong, Yuefei Zhang, Ruan Chi, Junxia Yu
    2016 年22 巻6 号 p. 759-770
    発行日: 2016年
    公開日: 2016/12/28
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    The simultaneous microwave-assisted ethanol reflux extraction of flavonoids and saponins from Astragalus was studied. Response surface methodology (RSM) was used to develop predictive models for simulation and optimization of the extraction process. Based on the single factor test, the multivariate regression equation was obtained by the RSM of five-factors and five-levels, which designed from the Central Composite Circumscribed Design program. The response surface and contour lines were determined by using the yields of Astragalus flavonoids and saponins as response values. The optimum conditions of the microwave-assisted ethanol reflux extraction were obtained as follows: liquid to solid ratio of 22 mL/g, extraction temperature of 62°C, ethanol concentration of 64% (v/v), extraction time of 22 min, and microwave power of 590 W. The yields of Astragalus flavonoids and saponins reached as high as 25.63% and 0.98%, respectively. Multiple regression equation is extremely significant for the prediction of practical production.

Food Science and Chemistry
Original papers
Note
Short communication
  • Zhe Liu, Toshiyuki Nakamura, Shintaro Munemasa, Yoshiyuki Murata, Yosh ...
    2016 年22 巻6 号 p. 847-851
    発行日: 2016年
    公開日: 2016/12/28
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    In the present study, we investigated the inhibitory effects of four tea catechins, including (−)-epicatechin (EC), (−)-epigallocatechin (EGC), (−)-epicatechin gallate (ECg) and (−)-epigallocatechin gallate (EGCg), on angiotensin converting enzyme (ACE) activity in vitro. Each catechin treatment significantly reduced the ACE activity with the order of potency being EGCg > ECg > EGC = EC. The addition of 1 mM borate significantly recovered the reduced ACE activities by tea catechins, suggesting that hydroxyl groups at the B-ring or at a galloyl moiety play an important role in the ACE-inhibitory mechanism. The covalent modification of ACE by tea catechins was also observed by a redox-cycling staining experiment. A Lineweaver-Burk plot indicated that EGC and ECg were non-competitive inhibitors. The galloylated catechins might more potently inhibit ACE activity in an allosteric manner through the interaction of the galloyl moiety with the non-catalytic site of ACE.

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