Jee Yun Jung

Chungbuk National University, Chinsen, North Chungcheong, South Korea

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Publications (6)8.63 Total impact

  • [Show abstract] [Hide abstract]
    ABSTRACT: When the color reflectance of red pepper powders and their yellow seeds were measured using a colorimeter, the mean lightness (L*), redness (a*), and yellowness (b*) values differed considerably between the pepper powders and seeds. On the basis of this difference, we determined the seed content in the red pepper powders by using the correlated reflectance values. As the seed content of the powders increased, both L* and b* increased, while a* decreased. The polynomial regression curve equation, $$ Y\left( {{\hbox{seed content}},{ }\% } \right) = 3.51 \times L * - 1.10 \times a * - 1.34 \times b * - 72.74 $$, was obtained from the tristimulus data (L*, a*, and b*) of all the samples used. This is an easy method for the determination of the seed content in red pepper powders and it can be applied to a similar system.
    Food Analytical Methods 01/2011; 4(1):23-27. · 1.97 Impact Factor
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    ABSTRACT: The aim of this study was to elucidate the Korean consumers’ aroma preference on wines. For this, a sensory test on 6 commercial red wines (5 imported and 1 domestic) was conducted by 250 panels and the volatile compounds of those wines were analyzed by gas chromatography-mass spectrometry. Sample 1 obtained the highest mean aroma acceptability score and analysis of volatile compounds revealed that it retained many kinds of esters and alcohols compared to other wines (including 2 acetate esters, 6 ethyl esters, 3 other esters, and 5 alcohols, mostly giving fruity aroma). Sample 1 was made by blending 2 varieties of grapes and this brewing technology might give a preferred aroma balance. The domestic wine, sample 2, made of ‘Campbell Early’ grape earned relatively higher acceptability score (2nd ranked), being considered its strong grape aroma. In the lower score group, higher concentrations of isoamyl alcohol, 1-isothiocyanto-propane, and volatile phenol were detected and their strong grassy or fatty odor might affect the lower sensory result. Strategies for production of consumer-preferred wines were suggested. Keywordswine-volatile compound-sensory test-‘Cabernet Sauvignon’-‘Campbell Early’
    Food science and biotechnology 01/2010; 19(1):43-49. · 0.70 Impact Factor
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    ABSTRACT: This study investigates the buffering effects of calcium salts in kimchi on total acidity, microbial population, and dextransucrase activity. Calcium chloride or calcium carbonate was added in dongchimi-kimchi, a watery-radish kimchi, and their effects on various biochemical attributes were analyzed. The addition of 0.1% calcium chloride produced a milder decrease in the pH after 24 days of incubation, which allowed the lactic acid bacteria to survive longer than in the control. In particular, the heterofermentative Leuconostoc genus population was 10-fold higher than that in the control. When sucrose and maltose were also added along with the calcium salts, the dextransucrase activity in the kimchi was elevated and a higher concentration of isomaltooligosaccharides was synthesized when compared with the control. Calcium chloride was determined as a better activator compound of dextransucrase than calcium carbonate, probably because of its higher solubility. Therefore, the results of this study confirm the ability of the proposed approach to modulate the kimchi fermentation process and possibly enhance the quality of kimchi based on the addition of dietary calcium salts.
    Journal of Microbiology and Biotechnology 12/2009; 19(12):1644-9. · 1.40 Impact Factor
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    ABSTRACT: D-form lactate is often found in fermented foods and excessive dietary intake of D-lactate may cause metabolic stress in both infants and patients. Leuconostoc citreum is a major lactic acid bacterium that produces D-lactate in fermented foods. The aim of this study was to change the pyruvate carbon flux in L. citreum from D-lactate into L-lactate by heterologous expression of L-lactate dehydrogenase (ldhL) gene. For this, ldhL from Lactobacillus plantarum was cloned and introduced into L. citreum using a shuttle vector pLeuCM. In the transformant, ldhL was successfully transcribed and L-lactate dehydrogenase was expressed. As a consequence of transformation, the ratio between D- and L-isomers was changed due to the increment of L-lactate and the decrement of D-lactate, but no significant differences were found in total lactate concentration between the host and transformant cells. This is the first report of metabolic engineering in Leuconostoc by modulating the central carbon flux into health-favored way.
    Journal of Biotechnology 09/2009; 144(2):160-4. · 3.18 Impact Factor
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    ABSTRACT: To investigate possible recycling of a brine solution for the production of salted cabbage (jeolimbaechu), bacterial cell counts in the brine solution and salted cabbages were measured after repeated salting processes. After a salting process with a 13% brine solution for 15 hr at 10°C, the salt concentration in brine and salted cabbage decreased to 9.0–9.9 and 1.5–3.2% (depending on parts), respectively. After 5 repetitions, the total microbial count in the brine solution and salted cabbage gradually increased to 8.9 and 8.7 log CFU/g, respectively. Polymerase chain reaction-denaturing gradient gel electrophoresis (PCRDGGE) showed that the marine bacteria, Pseudoalteromonas sp. and Halomonas sp. appeared from the 3rd batch; their intensities increased steadily and dominated the recycled brine solution. Meanwhile, Lactobacillus sakei found in the cabbage during the first salting process decreased with successive repetitions. These results show a high risk of marine microbial contamination in salted cabbage when the brine solution is re-used. Therefore, to re-use brine solution, application of proper inhibitory methods to prevent microbial cell growth in the brine solution is required. Keywordssalted cabbage–brine–NaOCl– Pseudoalteromonas – Halomonas
    Food science and biotechnology 20(1):223-227. · 0.70 Impact Factor
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    ABSTRACT: A polymerase chain reaction-denaturing gradient gel electrophoresis (PCR-DGGE) method was used to determine the presence and diversity of lactic acid bacteria (LAB) in takju, a traditional Korean rice wine. Bacterial DNAs were extracted from 15 commercial rice wines and amplicons of partial 16S rRNA genes were separated by DGGE and intense bands were sequenced. Lactobacillus (Lb.) paracasei, Lb. plantarum, and Leuconostoc pseudomesenteroides were detected in all samples and Lb. harbinensis and Lb. parabuchneri were found with above 80% frequency of occurrence. Unknown species of Lactobacillus were also widely detected. This result revealed that, regardless of products and raw materials, the distribution profiles of LAB in takju products have a common pattern comprising of above predominant species and, furthermore, takju can be regarded as a LAB-rich fermented food providing various probiotics. Keywords16S rRNA gene-lactic acid bacteria-polymerase chain reaction-denaturing gradient gel electrophoresis (PCR-DGGE)- takju
    Food science and biotechnology 19(3):749-755. · 0.70 Impact Factor

Publication Stats

13 Citations
8.63 Total Impact Points

Institutions

  • 2009–2011
    • Chungbuk National University
      • Department of Food Science and Technology
      Chinsen, North Chungcheong, South Korea
    • Korea Food and Drug Administration
      Seishō-gun, North Gyeongsang, South Korea