• 제목/요약/키워드: food science and technology

검색결과 19,166건 처리시간 0.046초

Effects of Gamma Irradiation on Inhibition of Urease Activity and Fishy Smell in Mackerel (Scomber japonicus) during Refrigerated Storage

  • Jeong, So-Mi;Kim, Han-Ho;Ryu, Si-Hyeong;Kang, Woo-Sin;Lee, Ji-Eun;Kim, Su-Ryong;Lee, Ga-Hye;Xu, Xiaotong;Byun, Eui-baek;Ahn, Dong-Hyun
    • Journal of Microbiology and Biotechnology
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    • 제32권6호
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    • pp.808-815
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    • 2022
  • In this study, gamma-irradiated mackerel (Scomber japonicus) meat was stored in a refrigerator for 20 days to examine the physicochemical changes related to fishy smell. The effect of gamma irradiation on the inhibition of the activity of crude urease extracted from Vibrio parahaemolyticus was also evaluated. Increased levels of trimethylamine (TMA) and volatile basic nitrogen (VBN) content, which are the main components causing fishy smell, were significantly reduced by day 20 of storage after gamma irradiation, indicating that freshness was maintained during storage. The ammonia nitrogen contents of 3, 7, 10, and 20 kGy gamma-irradiated groups were significantly decreased by 6.5, 15.2, 17.4, and 23.9%, respectively, compared to non-irradiated groups on day 20 of storage. In addition, urease activity decreased in a gamma irradiation intensity-dependent manner. Volatile organic compounds (VOCs) were measured during the storage of gamma-irradiated mackerel meat. The contents of ethanol, 2-butanone, 3-methylbutanal, and trans-2-pentenal, which are known to cause off-flavors due to spoilage of fish, were significantly reduced by day 20 of storage. Therefore, gamma irradiation can be considered useful for inhibiting urease activity and reducing fishy smell during fish storage.

Effects of ${\gamma}$-Irradiation on Immunological Activities of ${\beta}$-Glucan

  • Kim, Jae-Hun;Sung, Nak-Yun;Byun, Eui-Hong;Kwon, Sun-Kyu;Song, Beom-Seok;Choi, Jong-Il;Yoon, Yohan;Kim, Jin-Kyu;Byun, Myung-Woo;Lee, Ju-Woon
    • Food Science and Biotechnology
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    • 제18권5호
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    • pp.1305-1309
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    • 2009
  • This study evaluated the effects of $\gamma$-irradiation on immunomodulating properties and structural changes of ${\beta}$-glucan. ${\beta}$-Glucan solutions (10 mg/mL) were ${\gamma}$-irradiated at 10, 30, and 50 kGy. Splenocyte proliferation and cytokine (interferon-${\gamma}$ and interlukin-2) productions by ${\gamma}$-irradiated ${\beta}$-glucan were evaluated in in vivo and in vitro, and structural changes of ${\beta}$-glucan were also determined after ${\gamma}$-irradiation. ${\gamma}$-Irradiation on ${\beta}$-glucan at 50 kGy enhanced splenocyte proliferation and cytokine productions, (p<0.05) and cleft glycosidic bonds of ${\beta}$-glucan resulting in lower the molecular weight. These results indicate that the use of ${\gamma}$-irradiation on ${\beta}$-glucan may be useful for improving its immunological activity by lowering the molecular weight of ${\beta}$-glucan.

An In vitro Enzymatic Digestion Method for Estimation of the Acrylamide Contents of Foods

  • Kim, So-Hyun;Yoon, Ko-Woon;Kim, Mi-Kyo;Paek, Se-Hee;Choi, Dong-Mi;Oh, Sang-Suk;Park, Jin-Byung
    • Food Science and Biotechnology
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    • 제16권3호
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    • pp.493-495
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    • 2007
  • In this study, the acrylamide contents of foods were estimated via liquid chromatography (LC)/mass spectrometry (MS)/MS after the food matrix constituents had been degraded with digestive enzymes (i.e., pepsin and pancreatin) and extracted with water. The quantities of acrylamide released from samples of cereal, potato chips, peanuts, and coffee were $62{\pm}5.1,\;970,\;106{\pm}20$, and 890 ppb, respectively. No acrylamide was detected in samples of soybean curd (tofu), fish cake, and ham. Compared to the amounts of acrylamide detected after extraction with water only, we noted no significant differences in the soybean curd, fish cake, potato chip, ham, and coffee samples. However, the quantities of acrylamide released from the cereal and peanut samples were approximately 2-fold larger following pretreatment with the digestive enzymes. This study presents a new in vitro enzymatic digestion method which allows for a more accurate estimation of the acrylamide contents of foods.

Effect of Chemical Treatment with Citric Acid or Ozonated Water on Microbial Growth and Polyphenoloxidase Activity in Lettuce and Cabbage

  • Youm, Hyoung-Jun;Jang, Jae-Won;Kim, Kyu-Ri;Kim, Hyo--Jjung;Jeon, Eun-Hee;Park, Eun-Kyoung;Kim, Mee-Ree;Song, Kyung-Bin
    • Preventive Nutrition and Food Science
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    • 제9권2호
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    • pp.121-125
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    • 2004
  • Effects of chemical treatment with a citric acid solution or ozonated water on microbiological changes in lettuce and cabbage during storage were studied. Fresh lettuce and cabbage samples were cut into small pieces and treated by soaking in either ozonated water or a citric acid solution. After treatment, populations of total bacteria, yeast and mold, and E. coli were determined. Numbers of microorganisms increased during storage, but ozonated water and citric acid treatments retarded the increase in microbial growth. Among treatments, 1 % citric acid treatment was the most effective in terms of microbiological change and inhibition of polyphenoloxidase (PPO). For lettuce, citric acid treatment decreased the microbial growth overall by 1.5 log CFU/g and inhibited the PPO activity by 80%. These results indicate that chemical-treated lettuce and cabbage retained a better quality than those of the control during storage.