• Journal of Environmental Science International
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• v.10 no.4
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• pp.259-267
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• 2001

Investigations were carried out to observe the seasonal succession of phytoplankton, and viable counts of bacteria from the mid to lower reaches of Nakdong Fiver. An intensive monitoring was conducted from May to December 1999 biweekly at 6 sites in a main channel and 3 tributaries. Although there are several sites with high nutrient loading from the basin, all of study sites showed mesotrophic states owing to high discharge(June~September). Relatively low algal biomass and CFUs(mean of chi. a, $12.3{\pm}$11.5 $\mu\textrm{g}${\el}l$, CFUs : 1.8${\times}10^7$) were observed during the rainy season. The diatom population was dominant(over 85% of total community) year-long with peaks(Stephanodiscus hantzchii) in the fall and winter. Dominance of blue-green algal groups during the summer was not observed in the summer. Microorganisms peaked in the summer and fall(June~September), affected mainly by the inputs of phytoplankton and nutrients. Biomass of phytoplankton and CFU counts were higher in the Kumho River than other tributaries and main channel.

• Journal of Animal Science and Technology
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• v.63 no.2
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• pp.394-404
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• 2021

The objective of this study was to evaluate quality characteristics of low-nitrite emulsified-sausages (ESs, < 75 ppm) containing paprika oleoresin solution (POS) for replacing sodium nitrite (NaNO2). Pork ESs were prepared with four treatments (reference (REF), 150 ppm NaNO2; TRT1, 0 ppm NaNO2 + 0.1% POS; TRT2, 37.5 ppm NaNO2 + 0.1% POS; and TRT3, 75 ppm NaNO2 + 0.1% POS). The physicochemical and texture properties, microbial counts, residual nitrite and thiobarbituric acid reactant substances (TBARS) were measured during refrigerated storage of 35 days. Although TRT2 and TRT3 had lower levels of NaNO2, they had higher redness and yellowness than REF (p < 0.05). Microbial counts of total bacterial counts and Enterobacteriaceae of TRT2 and TRT3 were similar to those of REF (p > 0.05). Expressible moisture percentages (EM, %) of TRT2 and TRT3 were lower than those of REF (p < 0.05). TBARS values of TRT2 and TRT3 were not different from those of REF (p > 0.05). Among treatments, TRT1 had the highest TBARS values (p < 0.05). In conclusion, 0.1% POS in combination with 37.5 ppm NaNO2 would have quality characteristics similar to those of REF. Therefore, approximately 3/4 of the initial nitrite level could be replaced with 0.1% POS, and eventually developed healthier pork products.

• Korean Journal of Microbiology
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• v.23 no.3
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• pp.215-222
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• 1985

Distribution pattern and activity of heterotrophec bacteria were measured in the mudflat of Nakdong river estuary. In March and June, 1985, community sizes of amylolytic, lipolytic and proteolytic bacteria as well as total viable counts were measured. Vertical distribution of bacterial community size increased a few orders of magnitude from Narch to June. Heterotrophic activity was estimated in turnover time with $U-[^{14}C]-glucose$. Turnover time reduced considerably in June compared to that of March. To sxamine correlations for measured bacterial groups, turnover time and environmental factors, correlation coefficient matrix was obtained. These measured characteristics did not consistently correlate well with one another.

• Food Science of Animal Resources
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• v.34 no.1
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• pp.73-79
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• 2014

This study was performed to evaluate the quality characteristics of three deboned categories of chicken thigh meat: one which was slaughtered and deboned in the same plant (fresh); one which was slaughtered, deboned, frozen, and thawed in the same plant (frozen-thawed); and the last which was slaughtered in a plant, deboned in a different plant, but then transferred to the original plant (fresh-outside). Surface color, drip loss, 2-thiobarbituric acid reactive substances (TBARS) value, sensory evaluation, and total aerobic bacterial counts of the chicken samples were determined. Moreover, the torrymeter was used to measure the differences in freshness of the chicken meat. The surface color and the TBARS values did not show significant differences among the three categories. However, the total aerobic bacterial counts of fresh-outside and frozen-thawed chicken meat were significantly higher than the fresh chicken meat on the first storage day, and the drip loss of frozen-thawed chicken meat was significantly higher than the fresh-outside and fresh chicken meat. In addition, the sensory evaluation of frozen-thawed chicken meat was significantly lower than the fresh-outside and fresh chicken meat. Torrymeter values were higher in fresh chicken meat than fresh-outside and frozen-thawed chicken meat during the storage period. These results indicate that the quality of frozen-thawed chicken meat is comparatively lower than the fresh chicken meat, and the torrymeter values can accurately differentiate the fresh-outside and frozen-thawed chicken meat from the fresh ones.

• Food Science and Preservation
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• v.17 no.1
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• pp.30-35
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• 2010

Salt composition may affect the quality of Kimchi. We examined the quality of Kimchi prepared using different types of salt (Korean purified salt, Korean solar salt without bittern, Korean solar salt, Chinese purified salt, Chinese solar salt, and Australian solar salt). Kimchi was fermented for 7 days at $20^{\circ}C$. Following fermentation, the pH of Kimchi decreased during storage, but total acidity and salinity values increased. The type of salt used did not affect quality. Total bacterial counts were 4.18-4.37 log CFU/g initially, and increased markedly during fermentation. Lactic acid bacterial counts were 3.42-4.91 log CFU/g initially, but 7.31-7.79 log CFU/g after 7 days of storage. The sensory characteristics of Kimchi during storage did not vary with the type of salt used in fermentation.

• Food Science of Animal Resources
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• v.37 no.4
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• pp.494-501
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• 2017

This study investigated the effect of injecting pineapple concentrate and honey into low marbled beef in order to enhance its sensory qualities, particularly tenderness and flavor, without compromising its fresh appearance. Beef loin was injected with a solution of 6.0% pineapple concentrate, 2.5% honey, 0.5% monosodium L-glutamate, 0.5% phosphate, and 0.3% salt (w/w) to 120% (w/w) of initial meat weight and stored for 14 d. Non-injected beef loin served as a control. Total aerobic bacterial counts, surface meat color, shear force, reducing sugar content, and sensory evaluation of the beef were analyzed at 0.5, 7, and 14 d of storage. Injection did not affect the total aerobic bacterial counts or color of the beef. However, injection increased the stability of meat color, compared with that of the control, during storage. The shear force value was significantly lower in the injected beef than that in the control. The injected beef had a significantly higher reducing sugar content compared with that of the control. In sensory evaluation, tenderness, juiciness, flavor, and overall acceptance of the injected beef were significantly higher than those of the control at 0.5 d. In conclusion, injection of pineapple concentrate and honey can improve the sensory qualities of low marbled beef, during short storage periods, without changing the fresh appearance of the beef.

• Applied Biological Chemistry
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• v.49 no.2
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• pp.158-162
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• 2006

To determine freshness and quality change of tofu during storage, we manufactured a freshness indicator and monitored the surface pH, volatile basic nitrogen (VBN), thiobarbituric acid reacted substance (TBARS), total bacterial counts, and sensory evaluation. Tofu had a change in color of the freshness indicator after storage of 8 days at $4^{\circ}C$, and its pH and total bacterial counts reached 5.6 and 7.63 log CFU/g, respectively. VBN and TBARS values increased and reached the decay point at the time of color change of the freshness indicator. Sensory evaluation also indicated that samples were unacceptable by off-odor and decrease of firmness at day 8 of storage. These results suggest that a freshness indicator should be useful in determining expiration date of tofu products during marketing by indicating the microbial safety as well as sensory change.

• Korean journal of food and cookery science
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• v.22 no.6 s.96
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• pp.905-913
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• 2006

The properties of water soluble powder of propolis(WSP), made with different levels(0, 20, 40, 60, 80%) of ethanol extract of propolis(EEP) and hydrocolloid were investigated, along with the quality changes of its bread after 7 days' of storage at $30^{\circ}C$ The yield of WSP containing 40% EEP treated at $160^{\circ}C$ was the highest at 59.3% and the brown color of all the powders tended to be darkened with increasing EEP content. The turbidity of WSP treated at higher temperature was decreased in its aqueous solution (10%, w/w), and this was considered to be due to the presence of minute nonsoluble particles. Antioxidative activities determined by DPPH(1,1-diphenyl-2-picrylhydrazyl) were the lowest in WSP treated at $140^{\circ}C$, while those of the WSP samples prepared at 160 and $180^{\circ}C$ were as high as that of WSP containing more than 40% EEP, regardless of EEP concentration. The propolis breads with added WSP made at $160^{\circ}C$ were selected as the most desirable powder for subsequent study. Bread with WSP40 was the heaviest while the volume loss of WSP80 was the greast after baking. The moisture contents of the propolis bread were drastically decreased until 3 days' of storage, but it was thought that WSP might be ineffective for the prevention of moisture loss. The pH of breads without EEP was decreased after 3 days' of storage, while that of the WSP breads remained almost unchanged until 5 days' of storage. Total bacterial counts also exhibited decay levels during the storage. In conclusion, water soluble powder of propolis is useful as a natural antioxidative and antibacterial material in various types of food.

• Journal of Environmental Health Sciences
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• v.2 no.1
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• pp.21-24
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• 1975

During April and May, 1973 rain water samples were collected five different times in nine selected areas of Seoul city. The pH factor and bacteria counts were measured. The following results were obtained. 1. The lowest pH was 6.18 at Moon Rae Dong and the highest was 6.30 at Jong Am Dong. This difference is not significant at the 0. 05 level. 2. The pH factor did not vary significantly with the time of sample collection. 3. Dae Bang Dong had the highest Total Plate Count of $1.9\times 10^3/ml$, Bo Moon Dong and An Kook Dong had the lowest Total Plate Count at $4.1\times 10^2/ml$. 4. The total plate count varied greatly according to the time of sample collection. This result can be used to remove are pollutants. 5. The Total plate Count is nearly inversely proportional to the length of time during which the sample is collected.

• Journal of Environmental Health Sciences
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• v.43 no.6
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• pp.491-498
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• 2017

Objective: Bacterial abundance and community compositions have been examined in Asian dust events, clarifying their impacts on public health. This study aims to determine the bacterial community compositions and viable bacteria in Asian dust particles in the Asian dust or non-Asian dust event of March 2016. Methods: The dust samples were collected using the high volume air sampler or high volume cascade impactor, and bacterial 16S rRNA genes were amplified using PCR, followed by pyrosequencing. Bacterial diversity index, richness estimate and community composition in the particles were analyzed from the sequencing data using Mothur software. Results: The results showed that the diversity and richness during Asian dust events were higher than them in non-Asian dust events. The total bacterial community analysis showed that at the phylum Proteobacteria, Actinobacteria and Firmicutes were the most dominant of Asian dust events and non-Asian dust events. In addition, the bacterial colony counts were higher during Asian dust event, comparing with non-Asian dust event. Conclusions: This study showed that bacterial community and richness of Asian dust samples was more complex and higher than non-Asian dust samples in Gyeonggi-do, Korea, which could affect public health and environment. Thus, the continuous monitoring of Asian dust could be an alternative for managing airborne bacteria.