• Journal of the East Asian Society of Dietary Life
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• v.15 no.4
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• pp.405-412
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• 2005

Quality characteristics of squid-sikhae prepared by four different methods(SHM: sikhae method, SHM-LA; sikhae method added with L plantarum, MM; mixed method of sikhae method and salting method, MM-LA; MM method added with L plantarum) were investigated during fermentation at $20^{\circ}C$. The pHs of all the 6-days fermented sikhae samples were in the range of 4.01-3.76, meaning that there were no significant difference in pH according to the preparation methods. Number of total microbes(TM) were decreased, while the ratio of lactic acid bacteria against TM in SHM-LA and MM-LA was higher than those of SHM and MM. There were no differences in acid protease activity, while $NH_2-N$ content of SHM and MM were higher than those of SHM-LA and MM-LA. Amylase activity was the lowest in MM-LA. Proteins separated by SDS-PAGE belonged to 7-200 kDa, the major proteins (153<94<41 kDa) of the sikhae in all plots were disappeared at 6 days fermentation. In sensory evaluation, sour taste of MM was the highest, while it was the lowest in SHM-LA. Sweet taste, bitter taste, salty taste and hot taste were not significantly different Off-flavor was decreased in lactic acid bacteria added products. Scores of the softness and overall acceptability were the highest in SHM-LA. These results indicated that SHM-LA was the best method for the preparation of squid sikhae because of the enhancement of lactic acid fermentation and overall acceptability.

• Food Science of Animal Resources
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• v.32 no.1
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• pp.18-23
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• 2012

This study was conducted to survey the perception of domestic consumers about traditional pork dishes, and to utilize the survey result as a basis for the development of processed pork products. A survey was conducted on 218 domestic consumers regarding the following: general questions, propensity and preference to consume pork dishes, pork dishes feasible for export, and the types and problems of processed products feasible for export. The results of the survey showed that the respondents consumed pork dishes 3-4 times a month on average and they appeared to consume the pork dishes most frequently in specialized restaurants. The highest preference was shown in Samgyeopasal gui (grilled pork belly) and Galbi gui (grilled pork rib) among the pork dishes, whereas the lowest preference was shown in Kkubdegi gui (grilled pork skin) and Gookbob (boiled rice and pork served in soup). When the type of processed pork products available according to pork dishes were analyzed, the result showed that Samgyeopasal gui (grilled pork belly) and Nirbiani (slices of roast, seasoned pork in width) could be developed as a frozen product, Geyook Bokeum (stir-fried spicy pork), Bulgogi (Korean-style barbecued pork), and Galbi jjim (braised short ribs) could be developed as a retort product, and that Bossam (boiled pork eaten with a salty sauce and wrapped in greens), Pyeonyuk (slices of boiled pork), Jokbal (pork trotters), and Sundae (kneading together seasoned mixture of vegetables and glass noodles stuffing it into casings made of hog intestines, which are then tied off at the ends and boiled) could be developed as a vacuum-packed product. When the survey concerning the problems expected in the development of processed products using pork dishes was conducted, the result showed that there could be a texture change issue for Galbi gui, Samgyeopasal gui and Nirbiani; a preservation issue for Bossam, Pyeonyuk; a safety issue for Bulgogi and Geyook Bokeum; a taste and flavor change issue for Geyook Bokeum and Sundae; and a packaging issue for Gookbob.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.44 no.2
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• pp.104-110
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• 2011

This study was conducted to improve the food functional and sensory food quality of Hizikia fusiforme by the fermentation of lactic acid bacteria. Seven strains of lactic acid bacteria isolated from traditional Korean fermented food were inoculated and cultivated in H. fusiforme water extract. Among them, Lactobacillus brevis LB-20, isolated from Kimchi, was selected for further study by considering the results of bacterial growth, DPPH radical scavenging activity, and sensory evaluation. No significant differences in proximate compositions (moisture, crude protein, crude fat, and crude ash) were observed by the fermentation of L. brevis LB-20. The most dramatical change was the conversion from glutamate to ${\gamma}$-aminobutyric acid (GABA) in H. fusiforme water extract fermented by L. brevis LB-20. The GABA content increased approximately 60-fold after 48 hr of fermentation. The bacterial fermentation also resulted in low-molecularization of the extract. The particle size of the fermented extract became approximately 4-fold smaller than that of the law extract. In addition, the analysis of volatile flavor compounds using GC/MS revealed that the bacterial fermentation dramatically removed off-flavors such as acetaldehyde, haxanal, diallyl disulphide and 1-penten-2-ol in the H. fusiforme extract.

• Journal of the East Asian Society of Dietary Life
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• v.14 no.5
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• pp.513-518
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• 2004

The effect of polyethylene film(PE) packaging of golden mushroom wrapped with Korean paper containing 20% mica powder on the changes in weight, color, texture, PPO activity, number of total microbe(TM) and sensory quality during storage at 10℃ were investigated. The experiments were divided to 3 groups(control; only PE packaging, KP; PE packaging wrapped with Korean paper up and down of the sample, KPM; PE packaging with Korean paper containing 20% mica powder up and down of the sample). The weight of the mushroom in the KPM was the lowest until 9 days-storage, but the weight was the highest at 15 days-storage, showing 12.5% higher against the initial weight. L* values of the mushrooms in the control and KP treatment were decreased, but the value in the KPM treatment was maintained as the same of the initial value during storage. The increasing rate of a* and b* values in the all plots during storage was the lowest in KPM and in order of KPM

• Food Science of Animal Resources
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• v.18 no.2
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• pp.115-124
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• 1998

This study was carried out investigate hygienic conditions of domestic packing plant for export and the shelf-life by Japanese standards. vacuum packaged chilled port loins provided by five packers(A, B, C, D and E) were transported to Japan in the same condition, Four packers(A, B, C adn d) produced the samples as hygienic as possible and one packer produced loins in the traditional hygienic condition, In TTC(2,3,5-triphenyl tetrazolium chloride) test all samples showed the negative reaction from the date of the quarantine(14 days after slaughtering) to 50 days The numbers of total plate count(TPC) of A, B, C and D packers that were below 108CFU/g until 50 days were accepted by Japanese Standards but TPC of E packer was over 107CFU/g at 30 days. VBN values increased sig-nificantly(P<0.01) in samples of A,B and D packers in the samples of C packer and E packer at 5% and 0.1% level respectively. The pH values of the vacuum packaged chilled pork for export at 14 days after slaughtering were 5.43∼6.00 In sensory evaluation, A, B, C and D packers which improved hygi-enic condition produced the products with good color and appearance. low drip until 40 days storage at $0^{\circ}C$ But as the storage time increase off-flavor occured at 40days in A and D packer and at 50days in B and C packer. In conclusion according to the above results of microbiological physicochemical and sensory evalution the edible periods of Korean vacuum package chilled porks may be estimated to 40∼50 days for the packers who improved hygienic condition and the shelf lives were calculated as 32∼40 days from edible period by a factor of 0.8(safety coefficient) while that of the pork from E packer which was produced in the traditional hygienic condition was estimated to 30 days after slaughtering at $0^{\circ}C$ Therefore the shelf-life of the pork of E packer would be only 24 days.

• Food Science and Preservation
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• v.10 no.3
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• pp.278-283
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• 2003

Addition of ethanol and/or polylysine to kimchi was investigated to improve its microbial hygienic quality and to extend shelf-life. Ethanol was added to kimchi with several concentrations(0.3％, 0.6％, 0.9％) and stored at 10$^{\circ}C$. Addition of 0.6％ and 0.9％ ethanol showed apparent inhibitory effect on growth of microorganism, but any distinct difference was not found between those concentrations. Addition of ethanol was more effective on growth inhibition of coliform and lactic acid bacteria than others. Addition of 0.6％ and 0.9％ ethanol retarded apparently pH decrease and acidity increase. Although addition of 0.6％ ethanol in combination with 0.12％ polylysine showed good retardation of pH decrease and acidity increase, overall organoleptic quality was not good because of off-flavor and taste. Also, addition of 0.6％ ethanol showed good overall organoleptic quality.

• Journal of Korean Society of Environmental Engineers
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• v.31 no.1
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• pp.64-69
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• 2009

Musty and earth odors caused by geosmin and 2-MIB are the major complaints from the drinking water consumers. Therefore, early detection of geosmin and 2-MIB is the key to prevent off-flavor occurrence. In this study, a rapid method using stir bar sorptive extraction (SBSE) in combination with the GC/MS was investigated to analyze geosmin and 2-MIB in water. The SBSE method, a solventless extraction technique, was optimized and then applied to the analysis of geosmin and 2-MIB in water. The SBSE technique was found to be a simple and fast procedure that allows many samples to be extracted simultaneously using very small volume (10~20 mL). In addition, the SBSE method offered high recovery and good linear regression coefficient for the geosmin and 2-MIB. The good repeatability of this method can be deduced from the low RSD (7.2~7.6%) at 10 ng/L for geosmin and 2-MIB. The limit of detection was determined 1~2 ng/L and the limit of quantitation was 3~6 ng/L. Above all, the SBSE method proved to be a very practical technique for the analysis of geosmin and 2-MIB in water.

• Food Science of Animal Resources
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• v.33 no.1
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• pp.109-118
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• 2013

The objective of this study is to increase the utilization of duck by-products. The nutritional characteristics of four kinds of duck by-products (liver, heart, gizzard, and feet) were determined. The quality changes of four kinds of duck by-products were evaluated during frozen storage at $-20^{\circ}C$. The crude protein and cholesterol contents showed the highest level in liver while the crude fat content was determined to be the highest content in feet at 13.90%, and lowest in gizzard at 0.57%. Duck by-products contained USFA in the range of 48.69-77.66%, and the highest level in feet (p<0.05). During storage of duck by-products at $-20^{\circ}C$, the pH of duck by-products was in the range of 6.24-7.15, and there were no significant differences during the 4 mon storage period at $-20^{\circ}C$. Microbial counts of duck by-products except the gizzard were decreased significantly as storage time elapsed. In the sensory evaluation, overall acceptability of by-products (liver, heart, gizzard and feet) showed a tendency of decreasing value through storage, because off-flavor was increased with increased storage. Considering the combined results, one can conclude that duck by-products provide a good source of protein, and it was judged that the use of raw meat would be most appropriate within 3 mon of frozen storage.

• Korean Journal of Agricultural Science
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• v.45 no.4
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• pp.811-821
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• 2018

This study focused on the improvement of blueberry delivery service using pre-cooled ice and $SO_2$ pads to prevent an increase in the fruit temperature as well as decay. To maintain the fruit quality during low temperature storage, the effect of a $SO_2$ pad and modified atmosphere packaging was also examined. Harvested blueberries were precooled at $15^{\circ}C$, sorted, and packaged. And the fruits were placed in a similar environment as that for the parcel service. Part of the fruits were stored at $0^{\circ}C$ for long term storage. The air temperature in the delivery box increased along with an increase in the simulated delivery time regardless of the treatment. However, the rate of temperature increase was lower in the ice pad treatment. No significant difference was not found after 48 h. The oxygen concentration in the box ranged between 10.5 - 14.5% in the ice pad treatment, which was higher than that of the untreated control (7.5 - 11.9%) whereas the $CO_2$ concentration was lower in the ice pad treatment. No differences were found in the occurrence of off-flavor, decay, and sensory quality loss during the 48 hours of the parcel service simulation. The combined treatment of the $SO_2$ pad and modified atmosphere packaging (MAP) using a perforated film increased the shelf-life of the blueberry fruits, the overall quality such as firmness, and the soluble solid content was not different between the treatments except for the decay incidence. No decayed fruit was found in the combined treatment. However, the percentage of decayed fruit in the control was 25% on day 15 of storage and 75% on day 33 of storage, respectively.

• Journal of Korean Society on Water Environment
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• v.34 no.6
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• pp.661-668
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• 2018

Geosmin is volatile metabolites produced by a range of filamentous cyanobacteria which causes taste and odor problems in drinking water. Molecular ecological methods which target biosynthetic genes (geoA) are widely adopted to detect geosmin-producing cyanobacteria. The aim of this study was to investigate the potential production capability of 8 strains isolated from the Nakdong River. Ultimately, a suggestion for a genetical monitoring tool for the identification of geosmin producers in domestic waters was to be made. Geosmin was detected using solid phase microextraction gas chromatography mass spectrometry (SPME GC-MS) in two strains of Dolichospermum plactonicum (DGUC006, DGUC012) that were cultured for 28 day. The highest concentrations during the experiment period was $17,535ngL^{-1}$ and $14,311ngL^{-1}$ respectively. Additionally, geoA genes were amplified using two primers (geo78F/971R and geo78F/982R) from strains shown to produce geosmin, while amplification products were not detected in any of non-producing strains. PCR product (766 bp) was slightly shorter than the expected size for geosmin producers. According to the BLAST analysis, amplified genes were at nucleotide level with Anabaena ucrainica (HQ404996, HQ404997), Dolichospermum planctonicum (KM13400) and Dolichospermum ucrainicum (MF996872) between 99 ~ 100 %. Both strains were thus confirmed as potential geosmin-producing species. We concluded that the molecular method of analysis was a useful tool for monitoring potential cyanobacterial producers of geosmin.