http://chineseinput.net/에서 pinyin(병음)방식으로 중국어를 변환할 수 있습니다.
변환된 중국어를 복사하여 사용하시면 됩니다.
GOU, JINGYU,LEE, HYEON-YONG,AHN, JUHEE International Association for Food Protection 2010 Journal of food protection Vol.73 No.12
<P>The aim of this study was to characterize the physiological and molecular changes of Salmonella Typhimurium and Listeria monocytogenes in deionized water (DIW) and nisin solutions (100 IU/g) during high pressure processing (HPP). Strains of Salmonella Typhimurium and L. monocytogenes in DIW or nisin solutions were subjected to 200, 300, and 400 MPa for 20 min. The Weibull model adequately described the HPP inactivation of Salmonella Typhimurium and L. monocytogenes. Salmonella Typhimurium and L. monocytogenes populations were reduced to less than 1 CFU/ml in DIW and nisin solutions under 400 MPa. The highest b value was 5.75 for Salmonella Typhimurium in nisin solution under 400 MPa. L. monocytogenes was more sensitive to pressure change when suspended in DIW than when suspended in nisin. The pressure sensitivity of both Salmonella Typhimurium and L. monocytogenes was higher in DIW solution (141 to 243 MPa) than in nisin solution (608 to 872 MPa). No recovery of HPP-injured cells in DIW and nisin solutions treated at 400 MPa was observed after 7 days of refrigerated storage. The heterogeneity of HPP-treated cells was revealed in flow cytometry dot plots. The transcripts of stn, invA, prfA, and inlA were relatively down-regulated in HPP-treated nisin solution. The combination of high pressure and nisin could noticeably suppress the expression of virulence-associated genes. These results provide useful information for understanding the physiological and molecular characteristics of foodborne pathogens under high-pressure stress.</P>
Jingyu Gou,Lae-Seung Jung,이승환,안주희 한국식품과학회 2011 Food Science and Biotechnology Vol.20 No.5
This study was designed to evaluate the inactivation, detachment, and recovery properties of Listeria monocytogenes biofilms treated by the combined high hydrostatic pressure (HHP) with nisin under acidic conditions. Biofilm cells were treated at 400 MPa for 20min in different trypticase soy broth (TSB) solutions,including TSB at pH 7.0 without nisin (TSB7−N), TSB at pH 7.0 with nisin (TSB7+N; 1,000 IU/mL), TSB at pH 5.0without nisin (TSB5−N), and TSB at pH 5.0 with nisin (TSB5+N). The biofilm cells in TSB7+N were significantly inactivated after HHP treatment. The numbers of biofilm cells were reduced by more than 6 log CFU/mL in TSB5−N and TSB5+N. More noticeable changes in cell size and shape were observed in TSB5−N and TSB5+N, showing shortened and shrunk biofilm cells. These results demonstrate that the HHP treatment combined with nisin and acid could effectively inactivate L. monocytogenes biofilm and detached cells.
Application of High Pressure Processing for Extending the Shelf-life of Sliced Raw Squid
Jingyu Gou,Hua Xu,Geun-Pyo Choi,Hyeon-Yong Lee,안주희 한국식품과학회 2010 Food Science and Biotechnology Vol.19 No.4
This study was designed to evaluate the effect of high pressure processing (HPP) on the microbiological safety and quality of sliced raw squid during refrigerated storage. The sliced and vacuum-packed raw squid samples were treated at 200, 300, and 400 MPa for 20 min by using a custom-made high pressure processor. The numbers of psychrotrophic bacteria in the sliced raw squids treated at 200, 300, and 400 MPa were reduced by 0.5, 2.5, and >4.7log CFU/g, respectively. The amounts of trimethylamine (TMA) produced in the sliced raw squids were reduced by 20, 33, and 51% at 200, 300, and 400 MPa, respectively, as compared to the control. The amount of total biogenic amines (BAs) in the control significantly increased up to 1.70 mg/g after 10 days of refrigerated storage, while that in the 400 MPa-treated squid sample gradually increased up to 1.33 mg/g. The autolytic activity values in the control,200, 300, and 400 MPa-treated squid samples were 4.70,2.28, 2.18, and 1.55 nkat/g, respectively, after 20 days of refrigerated storage. The HPP effectively retarded the microbial growth, TMA formation, autolytic activity in the sliced raw squids. Therefore, the HPP could be used as an effective processing tool for improving microbiological safety and quality of seafood.
Jingyu Gou,Yunyun Zou,안주희 한국식품과학회 2011 Food Science and Biotechnology Vol.20 No.1
The phenol amount of Lygodium japonicum extracted by the pressure-assisted water extraction (PAWE)was noticeably increased to 12.8mg GAE/g when compared to the conventional extraction (9.3 mg GAE/g) (p<0.05). The highest antioxidant activity was observed at Polygonum aviculare extracted by the PAWE, showing the lowest EC_50value of 0.09 mg/mL. The lowest minimum inhibitory concentrations (MIC_99) of L. japonicum extracted by the PAWE were 2.59, 3.33, and 7.37 mg/mL, respectively,against Listeria monocytogenes, Salmonella Typhimurium,and Propionibacterium acnes. These results suggest that the PAWE can be an appropriate extraction method for enhancing biological and pharmaceutical properties of medicinal plants.
고징유(Jingyu Gou),조운운(Yunyun Zou),최근표(Geun-Pyo Choi),박영범(Young-Beom Park),안주희(Juhee Ahn) 한국식품영양과학회 2011 한국식품영양과학회지 Vol.40 No.8
본 연구는 조미오징어의 저장성을 향상시키기 위한 초고압 기술의 응용 가능성을 평가하였다. 포장된 조미오징어를 400 ㎫에서 20분간 처리한 후 초고압 처리되지 않은 대조군과 21일간 냉장보관을 하였다. 냉장기간 동안 미생물의 생육, DMA 함량, TMA 함량, 총 BA 함량 및 효소활성을 0, 7, 14, 21에 각각 평가하였다. 미생물의 수는 초고압 처리 후 대조군에 비교하여 효과적으로 2.77 log CFU/g을 감소시켰다(p<0.05). 대조군에서 DMA와 TMA의 함량은 냉장저장 7일 후 각각 15.99 ㎎/g과 42.82 ㎎/g까지 증가되었다. 초고압 처리된 조미오징어의 효소활성은 냉장저장 7일 후 4.32 nkat/g으로 대조군(7.13 nkat/g) 비교하여 유의성 있게 감소되었다. 그러므로 초고압의 응용은 조미오징어의 미생물학적 안전성과 저장성 향상시키기 위한 가공방법으로 이용될 수 있을 것으로 사료된다. This study was designed to evaluate the potential of using high pressure processing (HPP) for extending shelf life of seasoned squid during refrigerated storage. The vacuum-packed seasoned squid samples were subjected to 400 ㎫ for 20 min using a custom-made high pressure processor. Microbial counts, dimethylamine (DMA), trimethylamine (TMA), total biogenic amine, autolytic activity were determined on days 0, 7, 14, and 21 of refrigerated storage. The numbers of indigenous bacteria were effectively reduced by 2.77 log CFU/g after HPP treatment. The amounts of DMA and TMA produced in the control samples increased up to 15.99 and 42.82 ㎎/g after 7 days of refrigerated storage when compared to 5.27 and 10.21 ㎎/g the HPP-treated samples, respectively. The autolytic activity of the HPP-treated sample (4.32 nkat/g) significantly lower than that of the control (7.13 nkat/g) after 7 days of refrigerated storage. Therefore, HPP can be applied as a potential squid processing method microbiological safety and shelf life.
Functional Properties of Squid By-products Fermented by Probiotic Bacteria
Hua Xu,Jingyu Gou,Geun-Pyo Choi,Hyeon-Yong Lee,Juhee Ahn 한국식품과학회 2009 Food Science and Biotechnology Vol.18 No.3
The effects of probiotic bacteria on the functional properties of squid by-products were investigated during fermentation. Bifidobacterium longum, Lactobacillus acidophilus, Lactobacillus brevis, Lactobacillus casei, Lactobacillus paracasei, Lactobacillus rhamnosus, and Pediococcus acidilactici were used to ferment the squid by-products for 96 hr at 37℃. The numbers of all probiotics increased to 10?-10? CFU/g after 96 hr fermentation. No substantial pH changes were observed. L. rhamnosus and P. acidilactici showed the highest 2,2-diphenyl-1-picrylhydrazyl (DPPH) scavenging activities. Interleukin-6 (IL-6) and tumor necrosis factor-α (TNF-α) secreted from B cells increased after adding the extracts of probiotic-fermented squid by-products. The human NK cells were grown well in the B cell-growing broth cultured with the extracts of squid by-products fermented by L. rhamnosus and P. acidilactici. Trimethylamine (TMA) and dimethylamine (DMA) contents were significantly decreased after probiotic-fermentation. Therefore, L. rhamnosus GG and P. acidilactici can be used for the fermentation of squid by-products and their use would provide benefits in functional food products.