• Korean journal of food and cookery science
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• v.15 no.1
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• pp.68-72
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• 1999

Dried plantain (Plantago asiatica L.) was evaluated as a natural food preservative. The methanol extract of dried plantain at tie concentration of 2,000$\mu\textrm{g}$/ml completely inhibited the growth of B. subtilis, L. monocytogenes and V. parahaemolyticus. When the extract was added to noodles and rice cakes at the concentration of 1, 3 or 5%, less microbial growth was observed compared with the control group. While the noodles with 1% plautain extract were evaluated favorable in terms of color, chewiness and overall guality, 3% addition of the extract gave the best score for rice cakes.

• Journal of the Korean Home Economics Association
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• v.23 no.2
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• pp.37-43
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• 1985

The effect of irradiation at dose of 3~10 kGy on the extension of the shelf-life of sliced dried squid and dried file and on its quality were investigated during nine months of storage at room temperature. The number of microorganisms, TBA value and TMA-N content were used as objective indices concerned to the sensory evaluation. In the number of initial microbial loading, total bacterial count of sliced dried squid and dried file fish were $2.7{\times}10^{8}\;and\;2.0{\times}10^{5}$, yeast and mold were $5.7{\times}10^{5}\;and\;6.2{\times}10^{5}$ and coliform group were $2.1{\times}10^{5}$ and above 10 per gram of the samples, respectively. The number of total bacteria was sterilized by 99% with irradiation of 3~10 kGy and irradiation of above 7 kGy was shown to be effective for the radurization of yeast, mold and coliform group. TBA value of irradiated groups were higher than storage time. The TMA-N content of nonirradiated group was markedly increased by microbial spoilage during storage, however above 8 kGy irradiated group were indicated about 10 mg% after nine months storage. In the sensory evaluation, the nonirradiated group was off favor after three months storage and was changed in color of dried fishes but 7~10 kGy irradiated group were maintained good qualit compared with those of fresh samples after nine months storage at room temperature.

• Journal of the Korean Society of Food Culture
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• v.34 no.2
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• pp.201-207
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• 2019

This review summarizes the studies on a wide variety of yeast found in kimchi and the effects of yeast on kimchi fermentation, and discusses the direction for further research. Yeast belongs to the genera Trichosporon, Saccharomyces, Sporisorium, Pichia, Lodderomyces, Kluyveromyces, Candida, Debaryomyces, Geotrichum, Kazachstania, Brassica, Yarrowia, Hanseniaspora, Brettanomyces, Citeromyces, Rhodotorula, and Torulopsis have been identified using culture-dependent methods and metagenomics analysis. The application of yeast as a starter into kimchi has resulted in an extension of shelf life and improvement of sensory characteristics due to a decrease in the amount of lactic acid. On the other hand, some yeast cause kimchi spoilage, which typically appears as an off-odor, texture-softening, and white-colony or white-film formation on the surface of kimchi. In contrast to lactic acid bacteria, there are limited reports on yeast isolated from kimchi. In addition, it is unclear how yeast affects the fermentation of kimchi and the mechanism by which white colony forming yeast predominate in the later stage of kimchi fermentation. Therefore, more research will be needed to solve these issues.

• Food Science of Animal Resources
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• v.22 no.3
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• pp.240-246
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• 2002

The seasoned pork with soy sauce(SS) or Kochujang(SK) was manufactured using hind and fore leg as main raw material and the quality characteristics and shelf-life were investigated during storage at 5$\^{C}$ and 10$\^{C}$ after having packaged with air. The initial total aerobic plate counts(APC) of SS and SK were 5.24 and 5.75 log10 CFU/㎠, respectively. APC exceeded 7 log10CFU/cm2 after 10 days at 5$\^{C}$ and 6 days at 10$\^{C}$ far SS, and after 6 days at 5$\^{C}$ and 4 days at 10$\^{C}$ for SK, respectively. In the sensory test, the SS samples stored at 5$\^{C}$ and 10$\^{C}$ were assessed as lower than 3.0 points, the criterium of consumer acceptability, after 10 and 8 days, respectively. In the case of SK samples, the point of this time was at day 10 and 6, respectively when they were stored at 5$\^{C}$ and 10$\^{C}$. As storage time extended, pH and water content tended to decrease. Contrarily, the increase of TBA and VBN values was observed during storage and this was more pronounced at 10$\^{C}$ than at 5$\^{C}$ . The oxygen concentration in the package was 19.8 and 19.9% each for 55 and SK samples at the beginning but it was gradually decreased thereafter. On the other hand, the concentration of carbon dioxide was increased with the extension of storage. Based on the above results, the shelf-lives of seasoned pork were estimated to be 8 days for SS and SK stored at 5$\^{C}$ and 6 days for SS and 4 days for SK stored at 10$\^{C}$.

• Journal of Mushroom
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• v.10 no.4
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• pp.151-159
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• 2012

The button mushroom (Agaricus bisporus) is one of the most widely cultivated important edible mushroom species. In the breeding of new button mushroom, 'Seolgang' was developed by crossing two monokaryons 'CM020913-27' and 'SSU423-31'. Because of the secondarily homothallism, only a small percentage of the basidia produce 3 or 4 spores, which are mostly haploid (n) and do not fruit. Single spore cultures derived from these types of spores produce a vegetative mycelium that also contain a variable number of genetically identical nuclei per cell called monokaryon. The lack of clamp connections between monokaryon and dikaryon required a series of mycelial culture and fruiting test. After crossing, hybrids were cultivated on a small scale and on a commercial scale at a farm. For this, the spawn was made by a commercial spawn producer and the spawned compost by a commercial compost producer. Mycelial growth of 'Seolgang' on CDA was better at $20^{\circ}C$ and $25^{\circ}C$ when it was compared with that of '505 Ho'. The mature cap shape of new strain 'Seolgang' is oblate spheroid and the immature cap shape is round to oblate spheroid. The cap diameter was 41.2 mm on average. In comparison with white strain '505 Ho', the strain had a yield that was 9% higher. It produced fruiting bodies which had a higher weight on average per fruiting body and were 19% firmer with a good shelf life. Days of fruiting body were 3-4 days later than those of '505 Ho'. The physical characteristics such as elasticity, chewiness, adhesiveness were better than that of '505 Ho'. Genetic analysis of the new strain 'Seolgang' showed different profiles compared to '505 Ho', CM02913-27, SSU413-31, when RAPD primers A02 and O04 were used.

• Korean Journal of Breeding Science
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• v.42 no.6
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• pp.711-716
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• 2010

'Sanggang', a new cultivar of Agrocybe aegerita, was bred with mating between monokaryotic strains isolated from 'GMAG45109' and 'GMAG45107' in Mushroom Research Station, Gyonggi Province A.R.E.S. in 2009. The optimum temperature for the mycelial growth of 'Sanggang' was 26 to 28$^{\circ}C$ on PDA(potato dextrose agar) medium. The optimum temperature for the primordia formation and fruiting body development of 'Sanggang', was 18 to 20$^{\circ}C$. In the bottle cultivation of 'Sanggang', the period of spawn running was around 38 days at 22 to 23$^{\circ}C$ and the period from scratching of inoculum to harvest was 12 days. These characteristics of 'Sanggang' were not different from those of 'Mihwang' (control). 'Sanggang' had brown-colored pileus, whereas 'Mihwang' had yellowish brown-colored one. In bottle cultivation, 'Sanggang' hada little smaller but stronger stipe and pilus than 'Mihwang', and 'Sanggang', as well as 'Mihwang', had upright stipe. And 'Sanggang' was shown to have lower veil opening ratio than that of 'Mihwang' at harvest time.The yield of fruiting bodies of 'Sanggang' was 134 g/850ml bottle, which was similar to that of 'Mihwang'. Resistance of'Sanggang' against Trichoderma spp., as well as 'Mihwang', was weak. Freshness of 'Sanggang' was maintained for 13 days under storage temperature 4$^{\circ}C$, while that of 'Mihwang' was maintained for 10 days.

• Journal of the Korean Society of Food Culture
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• v.13 no.4
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• pp.275-291
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• 1998

Food irradiation is an emerging technology which offers many advantages such as reduction of microorganisms, extension of shelf-life of foods, reduction in the use of post-harvest chemicals, and destruction of insects and parasites. The commercial utilization of food irradiation, however, has been restricted because of the uncertainty of consumers' responses to it. Because success of food irradiation in the marketplace will depend upon their acceptability by consumers, this study focused on the consumers' perception and acceptance toward food irradiation in order to get basic data for commercial utilization of food irradiation and give information to consumers to help rational consumption behavior. The survey with 411 respondents living in Youngnam area was conducted during the spring of 1997 by the questionnaires. The results and implications from this study are as follows. First, consumers' knowledge about food irradiation is scanty. Two-thirds of respondents in the survey had not heard of irradiated foods and many people confused irradiation with radioactivity. In the willingness to accept food irradiation, one-third of respondents showed a wait-and-see attitude. This result indicated consumers had insufficient information about the irradiation process and nationwide education of food irradiation technology should be undertaken. Second, although the purchase and use of food are very important consumption behaviors, consumer education by mass communication has been rarely done. For the successful commercialization of food irradiation, the information provision by mass communication for the consumers should be made. Third, consumers generally worried about residual pesticide and intended to purchase irradiated foods if radioactivity was not retained in the foods. Therefore, food irradiation could be an alternative method to the use of pesticide Fourth, consumers pointed out that they wanted to extend shelf-life of milk and dairy foods, fish and seafood and to irradiate these foods. Therefore, research for the safety of irradiated foods should be continually conducted. finally, labeling for irradiated foods is needed to provide the information and to further increase public understanding. Especially, the labeling should show the definite reason why irradiation is being used. In conclusion, recently, under the circumstances that the commercial utilization of food irradiation and irradiation for the import and export products have been increased in many countries, many efforts are needed to improve the quality of irradiated foods, and prove the safety of them in Korea. In addition, consumer education for food irradiation should be given to help consumers to make decision for food purchase and use.

• Horticultural Science & Technology
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• v.28 no.4
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• pp.585-592
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• 2010

This study was conducted to investigate the effect of 1-MCP, an ethylene action inhibitor, and several postharvest treatments including ethylene scrubbing on fruit quality and respiration for keeping marketability in 'Janhowon Hwangdo' peach ($Prunus$ $persica$ Batsch). 1-MCP at the rate of $1.0{\mu}L{\cdot}L^{-1}$ showed best results in maintenance of fruit firmness and external appearance such as skin color. The ethylene production was strongly reduced by 1-MCP treatment at 0.5 or $1.0{\mu}L{\cdot}L^{-1}$ but respiration rate was only suppressed at $1.0{\mu}L{\cdot}L^{-1}$ during 6 days of shelf life at $20^{\circ}C$. Mature fruits (harvested 1 week before full commercial maturity) were much highly responsive to $1.0{\mu}L{\cdot}L^{-1}$ of 1-MCP compared to those of commercial maturity. At the concentration of $0.5{\mu}L{\cdot}L^{-1}$ of 1-MCP did not affect fruit marketability compared to untreated control. Beneficial effects of carbon ceramic as an ethylene scrubber were also found such as delay of firmness loss and deterioration of external appearance at $10^{\circ}C$, but these positive effects on fruit quality remained for only 5 days. The application of ethylene scrubber on the shipping carton boxes was effective on keeping firmness of immature fruit pretreated with 1-MCP when compared with mature fruit.

• Applied Biological Chemistry
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• v.41 no.6
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• pp.442-446
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• 1998

Chitosan has been known to have an antimicrobial activity. Chitosan samples having different molecular weights were tested for the antimicrobial activity against Escherichia coli in a liquid medium and on the paper sheets coated with different types of chitosan samples. In a liquid medium, Chitosan A $(Mw\;3,000{\sim}5,000)$ and B $(Mw\;200,000{\sim}500,000)$ showed minimal inhibitory concentration (MIC) of 40 and $10\;{\mu}g/ml$, respectively. The MIC of chitosan C $(Mw\;500,000{\sim}1,500,000)$ was similar to that of chitosan B. The paper sheets coated with chitosan A, B, and C also showed growth inhibition against E. coli. As a typical agricultural product, strawberry was tested for the extension of shelf life by using the chitosan-coated packaging papers. Storage experiments showed that chitosan-coated packaging papers extended the shelf life of strawberry at the chilling temperature of $4^{\circ}C$.

• Korean Journal of Microbiology
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• v.52 no.4
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• pp.471-481
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• 2016

The primary objective of this study was to investigate the effects of the bacteriocin-producing heterofermentative lactic acid bacteria (LAB) and acid-resistant yeast isolated from Mukeunji, a Korean ripened kimchi on shelf-life extension and quality improvement of sourdough. According to gene sequence analysis the heterofermentative LAB that showed the antimicrobial activity against bread-spoilage Bacillus strains were identified as Leuconostoc mesenteroides LAS112, Lactobacillus brevis LAS129, and L. mesenteroides subsp. dextranicum LAB137. In addition, the yeasts that were able to grow at acidic pH were identified as Pichia membranifaciens YS05, Pichia fermentans YS19, and Pichia anomala YS26. During sourdough fermentation the levels of acetic acid and bacteriocin produced by L. brevis LAS129 strain were higher than those of L. mesenteroides LAS112 and L. mesenteroides subsp. dextranicum LAS 137 strains, whereas LAS112 strain produced the highest levels of lactic acid. The maximum bacteriocin activity (640 AU/g) against Bacillus subtilis ATCC 35421 was obtained in sourdough fermented by mixed culture of L. brevis LAS129 and P. membranifaciens YS05 or P. anomala YS26. After 24 h of fermentation at $30^{\circ}C$, the viable cell counts of LAS129 ($10^9CFU/g$) in sourdough were higher than those of the YS05 or YS26 ($10^7CFU/g$). Meanwhile, the viable cells of bread-spoilage strain in sourdough fermented with these strains were significantly (P < 0.05) lower than the control group.