• Title/Summary/Keyword: Food Science

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Continuous Production of Fish Skin Gelatin Hydrolysate Using a Two-Stage Membrane Ractor (2단계 막반응기를 이용한 어피젤라틴 가수분해물의 연속적 생산)

  • Kim, Se-Kwon;Byun, Hee-Guk;Jeon, You-Jin;Yang, Hyun-Phil;Jou, Duk-Je
    • Applied Biological Chemistry
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    • v.37 no.2
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    • pp.130-141
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    • 1994
  • A continuous two-stage membrane (1st-SCMR, MWCO 10,000; 2nd-SCMR, MWCO 5,000) reactor was developed and optimized for the production of fish skin gelatin hydrolysate with different molecular size distribution profiles using trypsin and pronase E. The optimum operating conditions in the 1st-step membrane reactor using trypsin were: temperature, $55^{\circ}C$ ; pH 9.0; enzyme concentration, 0.1 mg/ml; flux, 6.14 ml/min; reaction volume, 600 ml; and the ratio of substrate to trypsin, 100 (w/w). After operating for 1 hr under the above conditions, 79% of total amount of initial gelatin was hydrolysed. In the 2nd-step using pronase E under optimum operating conditions[temperature, $50^{\circ}C$ ; pH 8.0; enzyme concentration, 0.3 mg/ml; flux, 6.14 ml/min; reaction volume, 600 ml; and the ratio of substrate to pronase E, 33 (w/w)], the 1st-step hydrolysate was hydrolysed above 80%. Total enzyme leakages in the 1st-step and 2nd-step membrane reactors were about 11.5% at $55^{\circ}C$ for 5hrs and 9.0% at $50^{\circ}C$ for 4 hrs, respectively. However, there was no apparent correlation between enzyme leakage and substrate hydrolysis. The membrane has a significant effect on activity lose of trypsin and pronase E activity for 1 hr of the membrane reactors operation. The loss of initial activity of enzymes were 34% and 18% in the 1st-step and 2nd-step membrane reactor, whereas were 23% and 10% after operating time 3 hr in the 1st-step and 2nd-step membrane reactor lacking the membrane, respectively. The productivities of 1st-step and 2nd-step membrane reactor for 8 times of volume replacement were 334 mg and 250 mg per mg enzyme, respectively.

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Bacteriocidal Effects of Ultraviolet Irradiation for Reducing Bovine Mastitis Derived from Environmental Contamination (우분뇨 유래 젖소 유방염 저감을 위한 자외선 조사 살균의 효과 규명)

  • Kim, Dong-Hyeok;Lim, Jung-Ju;Lee, Jin-Ju;Jang, Hong-Hee;Jang, Dong-Il;Lee, Seung-Joo;Lee, Hu-Jang;Min, Won-Gi;Kwon, Sun-Hong;Kim, Sang-Hun;Oh, Kwon-Young;Kim, Suk
    • Korean Journal of Environmental Agriculture
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    • v.27 no.4
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    • pp.435-440
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    • 2008
  • Bovine mastitis is an important disease causing serious economic loss in dairy production and food poison in public health. The major causative agents of bovine mastitis include Escherichia coli (E. coli), Streptococcus agalactiae (S. agalactiae), Staphylococcus aureus (S. aureus). These bacteria were found in milk and environmental condition such as feces, water, soil and so on. Recently, many cases of mastitis are derived from environmental contamination of micro-organisms, which important factors for the spread of this disease in farm. Ultraviolet irradiation (UV) has been used as disinfection for waste and water in clinical and industrial facilities. Moreover the UV irradiation has been used as useful bactericidal agents to remove bacterial biofilms in environmental condition. In this study, we determined the bacterial replication in different percentage of water content (PWC) in sterilized saw dust and feces complexes from farm, and results showed that slightly decreased growth pattern of E. coli and S. agalactiae but increased growth pattern of S. aureus in various PWC (200, 400 and 600%) until 144 h incubation. In the bacteriocidal effect of UV irradiation to bacteria in saw dust and feces complex, the results showed that bacteriocidal effect was depended on the UV irradiation time, irradiation distance and PWC. Especially the antibacterial activity of UV irratiation is stronger in low PWC (50%), long time irradiation (50 sec), and short distance (5 cm) than other condition of this study. Furthermore UV irradiation with stirring showed increased the bactericidal effect compared without stirring. These results suggested that bovine mastitis causing agents may survive long time in environmental condition especially saw dust and feces complexes in farm and can cause a various disease including mastitis. Moreover, these data can be used as basis for application and development of UV disinfection to control of bovine mastitis from environmental contaminated bacteria in dairy farm.

Characteristic of Seasonal Dynamics of Planktonic Ciliates at Four Major Ports (Busan, Ulsan, Gwangyang and Incheon), Korea (한국의 4개 주요항만(부산, 울산, 광양, 인천)에 분포하는 섬모충 플랑크톤의 계절동태 특성)

  • Yang, Seung-Woo;Lee, Joon-Baek;Kim, Young-Ok
    • Korean Journal of Environmental Biology
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    • v.36 no.2
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    • pp.217-231
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    • 2018
  • Planktonic ciliates play an important role in the food web of marine ecosystem as well as a bio-indicator for invasive species from ballast waters or from changing flow of ocean currents due to climate changes. This study was carried out to find some evidences for introduction of such invasive species using ciliate plankton in four major international ports of Korea. We surveyed the seasonal species composition of planktonic ciliate to find out the evidence for the invasive species at Busan, Ulsan, Gwangyang and Incheon ports from February 2007 to November 2008. A total of 45 ciliates species, belonging to 15 genera, were identified during the study period: 33 species occurred at Busan, 31 at Gwangyang, 30 at Ulsan, 18 at Incheon. The abundance of naked ciliates ranged from 566 to $65,151cells\;L^{-1}$ and that of tintinnids 10 to $5,973cells\;L^{-1}$. Based on vector species of ciliates reported from Coos Bay in Oregon, 13 vector species of tinitinnids were identified as follows, Eutintinnus lususundae, E. tubulosus, Favella ehrenbergii, F. taraikaensis, Helicostomella subulata, Stenosemella nivalis, Tintinnopsis ampla, T. beroidea, T. cylindrica, T. directa, T. lohmanni, T. radix, T. rapa. All vector species occurred at Gwangyang port. Most tintinnids were mainly neritic species throughout the survey, while warm water species occurred only in short period at Busan, Ulsan and Gwangyang ports that might be affected seasonally by Tsushima warm current.

Iron Status According to Serum Selenium Concentration and Physique in Young Female Adults (젊은 여성의 혈청 셀레늄 농도 및 체격에 따른 체내 철 수준)

  • Lee, Ok-Hee;Chung, Yong-Sam;Moon, Jong-Wha
    • Journal of Nutrition and Health
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    • v.43 no.2
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    • pp.114-122
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    • 2010
  • Se and Fe are trace minerals acting as antioxidant scavenging free radicals. Iron deficiency is the most frequently reported nutritional deficiency in females. Body iron status are known to be dependent not only upon dietary iron intake, but also upon micro-mineral nutrition and obesity. Antioxidants such as selenium are reported to play an important role on the regulation of erythropoiesis by protecting RBC membrane from antioxidative damage. In this study, iron status in young females and its relationships with selenium status and physique were examined. Serum selenium and iron concentrations were measured by HANARO research reactor using neutron activation analysis method (NAA-method). The proportion with iron deficiency and anemia were 27.1% and 8.6%, respectively in young females, but the proportion with iron deficient anemia was 1.4%. The mean serum selenium level was $12.0\;{\mu}g/dL$ and in normal range in the young women. The study participants were tertiled according to BMI and serum selenium levels. Serum ferritin and iron levels inclined with increasing BMI tertiles. Serum iron and RBC count were higher in middle selenium group than low selenium group. Individuals had significantly lower hematocrit level in the lowest tertile for their serum selenium levels compared with the highest tertile. The serum ferritin level was predicted 25% by BMI and RBC count 26.2% by the serum selenium level and body fat%. In conclusion, this study shows that body iron status in young adult females are influenced by obesity and body selenium status.

Analysis of Reproductive and Growing Performances by Sow Farm Sizes (국내 양돈장의 모돈규모별 번식 및 육성성적 분석)

  • Kim, Gye Woong;Ok, Young Soo
    • Reproductive and Developmental Biology
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    • v.39 no.1
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    • pp.23-28
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    • 2015
  • This study was carried out to investigate the reproductive and growing performances in sow farms located in Chungnam. Data collected from a total of 15 sow farms divided into 3 farm groups for 1 year were analyzed. The results obtained were as follows; The average of sow at small and large farms were 114.25 and 487.88 heads, respectively. And then, the difference among 3 groups in sow farm was not found significantly in farrowing rate. The significant difference among 3 farm groups was significantly found(p<0.05) in total litter size. The litter size born alive at sucking in small sow farm and middle farms were 9.93, and 10.48 pigs. The difference between small and large farms in number of pigs at weaning were significantly shown 8.89, and 9.35 pigs(p<0.05), respectively. The difference among 3 sow farms for ages at weaning showed significantly (p<0.05). The cycles of farrowing rate per year in small, large and middle farms were 2.17, 2.23 and 2.32, respectively. The significant difference among 3 sow groups was found in farrowing rate(p<0.05). The growing rate up to weaning for middle farms was significantly the higher level(94.70%) than that for other farms(p<0.05). The differences among 3 farm groups for marketing weight were not significantly shown.

Filtering Rate with Effect of Water Temperature and Size of Two Farming Ascidians Styela clava and S. plicata, and a Farming Mussel Mytilus edulis (수온과 개체크기에 따른 양식산 미더덕, 흰멍게, 진주담치의 여수율)

  • KIM Yong Sool;Moon Tae Seok
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.31 no.2
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    • pp.272-277
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    • 1998
  • Filtering rates of two farming ascidians Styela clava and S. plicata, and of a farming mussel Mytilus edulis were experimentally investigated with reference to effects of water temperature and size. Absorptiometric determinations of filtering rates were carried out in a closed system with experimental animals being decreased indicate dyes neutral red. Optical density (OD) of 440 nm in path length 22 mm cell used as the indication of food particles absorption was appeared directly in proportion with the concentration of neutral red dyes. The filtering rate F is calculated by Kim's equation $F\;=\;V(1-e^{-z})$, where V is the water volume ($\ell$) in the experimental jar, and Z is the decreasing coefficient of OD as meaning of instantaneous removal speed as In $C_t\;=\;In\;C_{o}-Z{\cdot}t$, in this formula $C_t$ is OD at the time t. Filtering rate of S. clava increased as exponential function with increasing temperature while not over critical limit, and the critical temperature for filtering rate was assumed to be between $28^{\circ}C$ and $29^{\circ}C$. In case of S. plicata, the critical temperature was to be below $13^{\circ}C$, and through the temperature range $15\~25^{\circ}C$ appeared a little difference in level even though with significant. M. edulis was not appear any significant effects by water temperature less than $29^{\circ}C$. The model formula derived from the results is as below, where F is filtering rate (${\ell}/hr/animal$), T is water temperature ($^{\circ}C$), and DW is dry meat weight (g) of experimental animal. $$S.\;Clava;\;F\;=\;e xp\;(0.119\;T-4.540)\;(DW)^{0.6745},\;T<29^{\circ}C$$) $$S.\;plicata;\;F\;=\;e xp\;(A_t)\;(DW)^{0.5675},\;(13^{\circ}C $$[A_t =-8.56+0.6805\;T-0.0153\;T^2]$$ $$M.\;edulis;\;F\;=\;0.3844\;(DW)^{0.4952},\;<29^{\circ}C$$)

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Development of Avermectin $B_{1a}$ High-yielding Mutants through Rational Screening Srategy based on Understanding of Biosynthetic Pathway (생합성 경로의 이해를 통한 Avermectin $B_{1a}$ 고생산성 변이주 개발)

  • Song Sung Ki;Jeong Yong Seob;Chun Gie-Taek
    • KSBB Journal
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    • v.20 no.5 s.94
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    • pp.376-382
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    • 2005
  • Avermectin (AVM) $B_{1a}$ produced by Streptomyces avermitilis via polyketide pathway is a secondary metabolite with powerful anthelmintic and insecticidal activities, thus being used as an efficient agent in the field of agriculture and animal health. It has been reported that a precursor for AVM $B_{1a}$ biosynthesis was isoleucine and the biosynthetic pathway of AVM $B_{1a}$ was closely similar to that of fatty acid. Based on understanding of the biosynthetic pathway of AVM $B_{1a}$, we intended to screen various mutants resistant against O-methyl threonine (OMT), an isoleucine-anti metabolite, and/or mutants resistant against p-fluoro phenoxy acetic acid (pFAC), an inhibitor of fatty acid biosynthesis. It was inferred that these mutants could produce AVM $B_{1a}$ more efficiently, due to the acquired capability of not only overproducing isoleucine intracellularly but also channelling metabolized carbon-sources into the polyketide pathway, thus leading to enhanced biosynthesis of AVM $B_{1a}$. The resulting mutant (PFA-1 strain) resistant against 100 ppm of pFAC was able to produce approximately 42 fold higher amount of AVM $B_{1a}$ compared to the parallel mother strain (4,200 vs. 100 units/l). In addition, through the process of continuous strain improvement program carried out by gradually increasing the OMT concentration, it was possible to obtain a more attractive mutant with greater AVM $B_{1a}$ production capacity (9,000 units/l). Notable was that significantly higher producer (12,000 units/l) could be selected through further screening of the resistant mutants, this time, to even higher concentration of PFAC. Meanwhile, through the analysis of AVM Bla production histograms (i.e., number of strains according to their AVM $B_{1a}$ biosynthetic ability) for the earlier strains in comparison with the high producers having the characteristics of resistance to OMT and pFAC, it was found that production stability of the high-yielding producers were remarkably improved, as demonstrated by the fact that larger proportion of the mutated strains had greater capability of AVM $B_{1a}$ biosynthesis ($71\%$ in the range between 5,000 and 7,000 units/L; $47\%$ in the range between 6,000 and 7,000 units/l). Based on these consequences, it was concluded that the rational screening strategy based on the understanding of the biosynthetic pathway of AVM $B_{1a}$ was very effective in obtaining high-yielding mutants with the features of enhanced production stability.

The Effect of Chinese Customer Coffee Benefit Sought on Korean Coffee Shop Satisfaction, Attachment, and Loyalty - Based on Mediating Effect of Korean Wave Attitude - (중국소비자의 커피제품 추구편익이 한국 커피전문점 만족도와 애착 및 충성도에 미치는 영향에 관한 연구 - 한류태도 매개효과를 중심으로 -)

  • Lee, Hyung-Ju;Suh, Ji-Youn
    • Culinary science and hospitality research
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    • v.22 no.5
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    • pp.151-166
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    • 2016
  • The purpose of this study is to understand the influence of Chinese customer coffee sought benefits on satisfaction with, and attachment and loyalty to Korean coffee shops. Based on a total of 200 samples obtained for empirical research from 10 Mar. to 25 July, 2015, of self-administrated questionaries completed by patrons in Beijing, Shanghai, Haerbin in China, data were analyzed for frequency, exploratory factor analysis, reliability analysis, correlation analysis, multiple regression and hierarchical multiple regression analysis. The results of this study are summarized as follows. First, it was found that Chinese customer sought pursuits (functional & experimental benefits, symbolic benefit) had an effect on satisfaction of Korea coffee shop. Second, satisfaction influenced Korean coffee shop attachment and loyalty. Third, Korean wave attitude had a mediating effect between satisfaction, attachment and loyalty. From the results, we can conclude following implications: First, by providing atmosphere of South Korea, menu, barista service, we can predict that Korean coffee brands can prevail in competition through active promotions of their brands. Second, Korean coffee brands can make a strategy that includes providing full service from trained South Korean baristas and hosting talk shows between baristas from South Korea. Third, providing the opportunity to visit South Korea for local cafe tours is a good social event. These results will help control marketing strategies in China. Limitations and future research directions are also discussed.

The Effects of Brand Experience and Personality on Consumer-Brand Relationships, Attachment, and Loyalty - A Comparison of Domestic and Global Brand Coffee Shops - (브랜드 체험 및 개성이 소비자-브랜드 관계, 브랜드 애착, 브랜드 충성도에 미치는 영향 - 국내외 브랜드 커피전문점 비교 -)

  • Hong, Ju-Young;Kim, Seong-Soo;Han, Ji-Soo
    • Culinary science and hospitality research
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    • v.22 no.5
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    • pp.231-251
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    • 2016
  • This study examined the effect of brand experience and personality on customer-brand relationships, brand attachment, and brand loyalty in domestic and global coffee shop brands. By comparing inter-structural relationships among factors between domestic brands and global brands, this study also provided strategic implications and directions for the effective marketing strategy of coffee shop brands. Data were collected through a self-administered survey of the consumers aged 20's to early 40's who used domestic and global brand coffee shops in Seoul and Kyunggi between August 1, 2014 and August 30, 2014. 500 surveys were distributed and 495 surveys were returned. Among them, data from 493 surveys were used for the analysis. The results from this study are as follows. First, it was found that the Think of experiences in coffee shop had a greater effect on consumer-brand relationship than the Sense-Feel. Second, the Sophistication of brand personality in coffee shop had a greater effect on consumer-brand relationship than the Excitement. Third, only Think of experience in coffee shop significantly impacted brand attachment, but Sense-Feel did not impact brand attachment. Fourth, only Excitement of brand personality in coffee shop significantly impacted brand attachment, but Sophistication did notact on brand attachment. Fifth, the consumer-brand relationship had a greater effect on brand loyalty than did brand attachment. Finally, the differences from a comparison analysis of domestic brands and global brands of coffee shop are as follows. In domestic brands, only the Sophistication of brand personality in coffee shop significantly impacted consumer-brand relationship. In global brands, the brand personality in coffee shop did not impact on consumer-brand relationship.

Comparison of Quality Characteristics among Chilled Loins Obtained from Jeju Black Cattle, Hanwoo and Imported Australian Beef (냉장한 제주흑우육, 한우육 및 호주산 수입우육의 품질 특성 비교)

  • Moon, Yoon-Hee
    • Journal of the East Asian Society of Dietary Life
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    • v.22 no.4
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    • pp.497-505
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    • 2012
  • The nutritional, physicochemical and sensory quality characteristics of chilled loins of Jeju Black Cattle, Hanwoo and imported Australian beef were compared. For nutritional properties, moisture and crude protein contents of Jeju Black Cattle beef were 65.91% and 17.39% respectively, the lowest among the comparison groups. On the other hand, their crude fat and crude ash contents were 15.89% and 0.79%, respectively, the highest among the comparison groups. There was a significant difference in crude ash content, but there was no significant difference in the other properties. The Fe and Zn contents of Jeju Black Cattle beef were 29.85 and 48.13 ppm, respectively, lower than those of Hanwoo beef, although the difference was not significant. These values were higher than those of Australian beef (p<0.05). There was no significant difference among the samples in contents of Ca, P, Na and Cu. The total amino acid and essential amino acid contents of Jeju Black Cattle beef were 16.81% and 9.08%, respectively, the lowest among the samples, although the difference was not significant. The ratio of essential amino acids to total amino acids of Jeju Black Cattle beef was 54.01%, the highest among the samples. The saturated fatty acid (43.25%), stearic acid (13.51%), linoleic acid (2.39%) and essential fatty acid (2.47%) contents of Jeju Black Cattle beef were the lowest. However, their unsaturated fatty acid (56.69%), oleic acid (47.80%) and MUFA/SFA ratios were the highest, and there were significant differences compared with Australian beef. There was no significant difference in the PUFA/SFA ratio. Among physicochemical properties, redness ($a^*$) of Jeju Black Cattle beef was the highest while melting point was the lowest (p<0.05). There were no significant differences in lightness ($L^*$), yellowness ($b^*$), pH, water holding capacity, cooking loss or shear force value. For sensory properties, raw meat aroma, cooked meat aroma and palatability of Jeju Black Cattle beef were superior compared to other comparison groups, with significant differences in comparison with Australian beef (p<0.05). However, there were no significant differences in taste, juiciness, or tenderness of cooked meat.