• 한국물환경학회지
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• 제37권1호
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• pp.1-9
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• 2021

The depletion of dissolved oxygen (DO) in urban streams has a profound effect on the aquatic ecosystem; however, the change in DO by resuspension of sediments and the cause have not been sufficiently investigated. In this study, the physicochemical properties (particle size, and the content of organic and heavy metals) of the sediments of an urban stream (Anyang Stream) and the characteristics of water quality changes (DO, dissolved organic carbon (DOC), dissolved nitrogen (DN), sediment oxygen demand (SOD), and adenosine triphosphate (ATP)) by sediment resuspension were investigated. The sediment content of fine particles (< 0.2 mm) increased from 36.7% to 52.7% from the upstream to the downstream, and the contents of heavy metals and organic matter of the sediment were also higher towards the downstream. The depletion of DO by resuspension was observed in the sediment at the downstream sites (P8, P9), where the fine particle content was high, and biological SOD (BSOD) was more than 88% compared to the total SOD. The increase in BSOD coincided with the increase in ATP. It was also confirmed that the depletion of DO could increase the amount of heavy metals (such as Fe, Mn, and Pb) released from the sediment. Based on the above results, it can be concluded that resuspension of sediments induces rapid water quality changes and may cause accidents, such as fish mortality, during rainfall, and such a water quality effect can be more pronounced in sediments with a high content of fine particles and organic matter and high biological activity.

• 한국식품저장유통학회지
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• 제18권2호
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• pp.165-170
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• 2011

본 연구에서는 새찰쌀보리의 보리밥 제조 적성을 살펴보기 위하여 영양성분 및 취반특성을 분석하였고, 보리밥의 관능평가와 조직감을 측정하였다. 새찰쌀보리의 수분은 11.6%, 조단백질은 10.8%, 조지방은 1.6% 및 조회분은 1.1%이었으며, ${\beta}$-glucan은 3.7%, 불용성 식이섬유는 10.8%, 수용성 식이섬유는 9.5%, 총 식이섬유는 20.3%로 나타났다. 새찰쌀보리의 호화개시온도는 $66.5^{\circ}C$ 이었고, 최고, 최종, 강하 및 치반점도는 각각 383.2, 231.3, 207.5 및 55.6 RVU로 나타났다. 새찰쌀보리의 취반특성에서는 흡수성이 232.2%, 퍼짐성이 405.3% 및 용출 고형물이 3.5%로 나타났다. 보리밥의 색도는 가수량이 증가할수록 명도는 증가하였으나 적색도와 황색도는 감소하였다. 보리밥의 관능평가 결과, 가수량이 많을수록 색깔과 단단함은 낮았으나 질은 정도와 종합적 평가는 높게 나타났으며, 종합적 평가가 높은 2.1배를 최적 가수량으로 선정하였다. 최적 가수량 조건에서 제조한 보리밥의 조직감 측정 결과, 경도는 1.2 kg, 응집성은 4.0, 탄성은 1.0, 검성은 5.1, 씹힘성은 5.3, 부착성은 0.2 kg 및 부착성/경도는 0.8로 나타났다.

• Fisheries and Aquatic Sciences
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• 제26권10호
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• pp.593-604
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• 2023

Post-harvest handling and hygienic level of aquatic products significantly affect the quality and level of safety. Cold chain control is one of the determining factors for the quality of fish and the bacterial community that grows on the fish. Identification of spoilage bacteria and pathogens in aquatic products must be made because it will determine the physical and chemical quality. A molecular identification method with high sensitivity is the solution. This study aims to identify the quality of fish and bacterial communities that grow. The research procedures included sample collection, pH measurement, drip loss measurement, transportation and cold storage treatment, DNA extraction, DNA sequencing, sequence analysis, and bioinformatics analysis. The conclusion obtained from this study is that the simulation of the cold chain system applied to eastern little tuna does not significantly affect changes in the water activity value, pH, and drip loss. The insignificant change indicates that the eastern little tuna samples are still in good quality. The bioinformatics analysis showed the highest diversity and abundance of the bacterial community came from the Gammaproteobacterial class.

• 한국환경과학회지
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• 제5권1호
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• pp.15-23
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• 1996

During the last two decades, many industrial complexes for heavy and chemical industries have been established along the Korean coastline, thereby increasing the pollution materials burden on the coastal environment of seawater. Masan Bay is one of the most polluted coastal areas in Korea and the main soures of pollutants are domestic and industrial wastewater from Masan, Changwon. This study was aimed to evaluate relationships among the physicochemical parameters in the bottom water of Masan bay and to examine environmental factors affecting to pollutions of seawater by factor analysis. 'rife factor loading, 1 is showed higher increasing inclination after 1989 year in station 1. The variance of pollutant materials is showed 43.7% in which the coastal inflow water is indicated external loadings(factor 1 : NO3--N, TN, factor 4 : SiO2-Si) corresponded to domestic sewage, industrial wastewater, and earth-sands in the bottom water of Masan bay And the internal loadings(factor 2 : SS, salinity, factor 3 . W.T., DO) are explained 33.8%'corresponded the phenomena of sedimentary layer and oxygen concentration. Therefore, The external loadings are explained by the higher factor pollutantal variance in Masan bay.

• 생태와환경
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• 제42권3호
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• pp.271-279
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• 2009

VC는 국제적인 발암등급 체계인 IRIS, IARC, ESIS에 의해 인체발암물질로 평가되고 있으며, 경구, 호흡, 경피 노출 경로를 통해 간세포 다형성 등을 유발하는 것으로 보고된 바 있다. 또한 VC는 자연계에서 쉽게 분해되지 않는 유기 염소계용제로서, 대기, 지표수, 지하수, 먹는물, 토양으로 유출되어 인체를 포함한 환경을 오염시킬 가능성이 높은 것으로 나타났다. 현재 우리나라의 수질환경기준과 먹는물 기준에서는 VC에 대한 규제 항목 및 기준치가 제시되어 있지 않으나, 인체 및 수생태계 위해 우려가 있어 특정수질유해물질 및 수질오염물질로 지정된 바 있다. US EPA, 일본, WHO 등 선진국에서는 법적 항목 및 기준치로 VC를 제도적으로 관리하고 있다. 특히 우리나라에서는 2004년 한강 및 낙동강 유역에서 $0.8\sim4.7{\mu}g\;L^{-1}$ (검출한계 $0.1{\mu}g\;L^{-1}$),개별배출업소 유출수에서 $10.6\sim668{\mu}g\;L^{-1}$의 농도로 VC가 검출된 사례가 있으며, 독일, 일본, 미국 등의 국외에서 검출된 $0.03\sim566{\mu}g\;L^{-1}$ 농도보다 국내 수계 내 VC의 분포 수준이 높은 것으로 나타났다. 국내 인체 위해성 평가 결과 VC에 대한 위해 우려가 높은 것으로 평가된 바 있으며, 생태 위해성 평가는 자료 부족으로 보류된 바 있다. 이 때 활용된 모니터링 자료는 일부 지점 및 단회 기반의 신뢰성 다소 낮은 자료에 국한되므로 지속적인 모니터링 사업을 통해 신뢰성 높은 자료로 대체될 필요가 있다. 또한 물 환경 내 생태독성연구는 일부 시험증에 국한되어 있고, 실험 설계도 VC의 수체 내 농도 감소를 고려하지 않아 결과치가 과다 산정되었을 가능성이 높다. 따라서 지속적으로 다양한 수서생물을 활용한 VC의 생태 독성 자료가 생성되어야 추후 VC에 대한 신뢰도가 높은 생태 위해성 평가가 수행될 것으로 사료된다.

• 한국식품조리과학회지
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• 제23권4호통권100호
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• pp.502-510
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• 2007

This study investigated the utilization of turmeric (Curcuma aromatica Salab.) for tofu manufacture and its effects on the quality characteristics and shelf-life. Various concentration (0.000%, 0.005%, 0.010%, and 0.015%) of turmeric were used to evaluate the shelf-life during tofu storage for 12 days at $10^{\circ}C$. The pH decreased with an increasing storage period, but the 0.010% and 0.015% tofu showed lower pH value than the 0.000% tofu, the acidity decreased with an increasing storage period. The water content of the turmeric tofu decreased with an increasing storage period. The turbidity gradually increased until 6 days of storage, and then rapidly increased at 12 days of storage. The microbial count of the 0.015% tofu was lowest during the storage period. In measuring the turmeric tofu color, the L- and a--values decreased during the storage period, while the b--value increased. In the texture analysis, hardness, gumminess, and brittleness of the turmeric tofu decreased 12 days of storage. Cohesiveness and springiness increased with an increasing storage period. In the sensory evaluation, Smoothness, after taste, and overall taste were highest for the 0.010% tofu. For the overall acceptability, the 0.010% tofu (with 0.45% mixed coagulant) attained the highest score.

• 한국축산식품학회지
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• 제38권2호
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• pp.403-416
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• 2018

In this study, the dietary effects of probiotics with a liquid application system on meat quality and physicochemical characteristics of pigs were evaluated. A total of 80 Landrace${\times}$Yorkshire${\times}$Duroc (LYD) 3-way crossbred pigs (average age $175{\pm}5d$) were assigned to a conventional farm and a probiotics farm equipped with a liquid probiotics application system (40 pigs in each farm). The two treatments were: CON (diet without probiotics) and PRO (diet with probiotics). Dietary probiotics decreased shear force in the longissimus muscle compared to the control group (p<0.05). The treatment diet did not affect backfat thickness, carcass weight, meat color, cooking loss, water holding capacity (WHC), and drip loss. Dietary probiotics significantly reduced ash, salinity, and pH (at 5 and 15 d) (p<0.05). There was no significant effect on thiobarbituric acid reactive substance (TBARS) values. Polyunsaturated fatty acid (PUFA) and omega fatty acids (${\omega}3$ and ${\omega}6$) were significantly (p<0.05) higher in the PRO group, whereas monounsaturated fatty acid (MUFA) was decreased. The free amino acid composition, serine, lysine, histidine, and arginine levels were significantly lower in the PRO than in the control group. The treatment group exhibited higher nucleotide compounds (hypoxanthine, inosine, GMP, IMP) than the controls. Also, levels of ascorbic acid and thiamin were significantly different (p<0.05), while minerals were not significantly different between the groups. In conclusion, feeding of probiotics had effects on shear force, ash, salinity, pH, PUFA, and some amino acids which related to taste and flavor without any negative effects on the pigs' carcass traits.

• 한국식품조리과학회지
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• 제22권3호통권93호
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• pp.270-281
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• 2006

The study investigated the effect of prefermentation of Bifidobacteria longum and Lactobacillus plantarum on baking quality. Firstly, two kinds of prefermentation were cultured using two lactic acid bacteria, Bifidobacteria longum and Lactobacillus plantarum. White pan bread baked with dough that had undergone these two prefermentation methods was compared with that baked with a non-prefermented control. The physicochemical properties of the three breads were analyzed, and then the physicochemical and sensory properties of the dough and baked bread were cross-analyzed. The pH prefermentation of Bifidobacteria longum was lower than that of Lactobacillus plantarum, whereas the titratable acidity was higher. Compared to the results from analyzing the prefermentation of Lactobacillus plantarum, the prefermentation of Bifidobacteria longum was expected to give positive effects on enriching the bread flavor by creating acetic acid at a level three- to eight-fold higher than that of Lactobacillus plantarum. According to the mixogram data, the optimum ending time for both Bifidobacteria longum prefermentation and Lactobacillus plantarum was around 4.5 to 5 minutes. The speed of dough materialization decreased with increasing prefermentation culture time. The baked bread with added Bifidobacteria longum had a higher water content. However, the other contents were not influenced by prefermentation, but were by culture time. The specific loaf volume, oven spring and baking lass rate all peaked at 20 hours after culture for both prefermentation cultures. The sensory test results indicated the highest prefermentation for the bread baked with prefermented Bifidobacteria longum doughwith a culture time ranging from 20 to 26 hours. In addition, the bread baked with prefermented Lactobacillus plantarum dough gave the highest preference when cultured for 20 hours.

• Asian-Australasian Journal of Animal Sciences
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• 제29권12호
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• pp.1782-1789
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• 2016

This study evaluated the effect of vacuum and modified atmosphere (40% $CO_2+60%$ $N_2$, MA) packaging on the chemical composition, physicochemical properties and sensory attributes of chill-stored meat from 10 fallow deer (Dama dama) bucks at 17 to 18 months of age. The animals were hunter-harvested in the forests of north-eastern Poland. During carcass dressing (48 to 54 h post mortem), both musculus longissimus muscles were cut out. Each muscle was divided into seven sections which were allocated to three groups: 0, A, and B. Samples 0 were immediately subjected to laboratory analyses. Samples A were vacuum-packaged, and samples B were packaged in MA. Packaged samples were stored for 7, 14, and 21 days at $2^{\circ}C$. The results of the present study showed that the evaluated packaging systems had no significant effect on the quality of fallow deer meat during chilled storage. However, vacuum-packaged meat samples were characterised by greater drip loss. Vacuum and MA packaging contributed to preserving the desired physicochemical properties and sensory attributes of meat during 21 days of storage. Regardless of the packaging method used, undesirable changes in the colour, water-holding capacity and juiciness of meat, accompanied by tenderness improvement, were observed during chilled storage.

• 한국축산식품학회지
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• 제40권6호
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• pp.946-956
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• 2020

To identify the effect of sodium-alternative curing salts on the quality properties of salami through the ripening process, four salami treatments were prepared with different curing salts, T1 (-control, NaCl 1.9%), T2 (+control, NaCl 1.9%+NaNO₂ 0.01%), T3 (KCl 1.9%+NaNO₂ 0.01%), and T4 (MgCl₂ 1.9%+NaNO₂ 0.01%), under 40 days ripening conditions. Sodium-alternative salts (T3 or T4) showed characteristically different quality traits compared with T2. Especially, T3 had lower pH, water activity, volatile basic nitrogen, and lipid oxidation after 20 days of ripening period, compare with T2 or T4 (p<0.05). Sodium nitrite had critical impact on increased a* values, and T3 showed higher a* values compared with T2 or T4 (p<0.05). Sodium nitrite reduced initial growth of coliforms but sodium-alternative salts did not affect microbial growth patterns. T2-T4 containing sodium nitrite had higher content of umami nucleotide flavor compounds compared with T1, regardless of the chlorine salt species. The combined use of sodium-alternative curing salts and minimal sodium nitrite was found to be an applicable strategy on development of low sodium salami without a trade-off of the product quality.