• Korean Journal of Food Science and Technology
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• v.38 no.5
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• pp.621-627
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• 2006

To characterize aroma properties of burnt beef reaction flavor manufactured by extrusion, volatile flavor compounds and aroma-active compounds were analyzed by simultaneous steam distillation and solvent extraction (SDE)-gas chromatography-mass spectrometry-olfactometry (GC-MS-O). Hydrolyzed vegetable protein (HVP) was successfully extruded with precursors (glucose, cystine, furaneol, thiamin, methionine, garlic powder, and lecithin) at $160^{\circ}C$, screw speed of 45 rpm, and feed rate of 38 kg/hr. Sixty eight volatile flavor compounds were found in burnt beef reaction flavor. The number of volatile flavor compounds decreased significantly when HVP was extruded either with furaneol-free precursors or without precursors. Twenty seven aroma-active compounds were detected in burnt beef reaction flavor. Of these, methional and 2-methyl-3-furanthiol were the most intense aroma-active compounds. It was suggested that furaneol played an important role in the formation of burnt beef reaction flavor.

• Journal of the Korean Society of Food Culture
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• v.31 no.4
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• pp.261-268
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• 2016

The purpose of this study was to survey the perception and preference for Korean food among Chinese students residing in Korea (Chinese foreign students, N=69) and China (Chinese-locals, N=98). A total of 76.8% of Chinese foreign students and 70.4% of Chinese-locals had ever eaten Korean food in China before visiting Korea, and motivation to try Korean food at first was 'easy access to Korean food restaurants' (Chinese foreign students 38.6%, Chinese-locals 44.9%). The most important factors in selecting Korean food were 'taste' and 'price' (Chinese foreign students 72.7% and 18.2%, Chinese-locals 59.1% and 22.7%, respectively), and needed improvements for Korean food were 'spicy and salty taste' and 'nutritional aspect' (Chinese foreign students 54.5% and 25.8%, Chinese-locals 33.3% and 36.4%, p<0.05). The scores for perception of Korean food were significantly lower in Chinese-locals (2.99) than in Chinese foreign students (3.31)(p<0.001). Chinese foreign students preferred Bulgogi (20.5%), Neobiani (20.1%), and Galbijjim (17.9%), whereas Chinese-locals preferred Bulgogi (16.1%), Gimbap (16.1%), and Samgyetang (15.2%) (p<0.001). The most preferred condiment was 'Garlic' (18.0%) in Chinese foreign students, and 'Red pepper powder' (16.4%) in Chinese-locals. The results of the study can be used as a foundation to prepare a globalization strategy for Korean Food.

• Applied Biological Chemistry
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• v.34 no.3
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• pp.235-241
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• 1991

Several spices in the range of $1{\sim}3%\;(w/w)$ were added during Kimchi preparation in order to investigate their effects on the chemical changes and fermentation rate. The results showed that addition of red pepper powder by 2% slightly increased the fermentation rate reaching max. value after 36 hours, while 3% addition gradually increased its rate without max. point. Generally higher reducing sugar and acidity were measured for red pepper added Kimchi. The fermentation rate and its max. point were significantly increased as more garlic added and the max. value of ascorbic acid produced was also increased. Little effects were found for Welsh onion and ginger on Kimchi fermentation.

• Journal of the Korean Society of Food Science and Nutrition
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• v.28 no.1
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• pp.33-39
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• 1999

Traditional kakdugi prepared from salted radish by the addition of fermented shrimp or anchovy sauce along with seasonings and spices, e.g., red pepper powder, garlic or ginger, which has been examined for the formation of volatile nitrosamine(NA) during its fermentation at 5oC and 17oC. Changes of acidity were increased; while, those of ascorbic acid and pH were continually de creased and besides concentrations of salt were scarcely observed during the fermentation of kakdugi at 5oC and 17oC. High initial levels of nitrate in radish followed by a gradual decreased in nitrate concentration, along with increasing levels of nitrite, during its fermentation. During the fermentation of kakdugi, NA such as N nitrosodimethylamine(NDMA) and N nitrosodiethylamine(NDEA) was identified; these NA in kakdugi that had been prepared with shrimp sauce contained in the higher levels than kimchi that had been prepared with anchovy sauce, and both NDMA and NDEA were detected higher levels in the fermented sample at 17oC than in the fermented sample at 5oC. In kakdugi, NDMA and NDEA levels were continually increased during its fermentation; its levels after 35 days fermentation at 17oC were 0.5~16.7 and 0~5.2 g/kg in added shrimp sauce sample, 0. 5~8.7 and 0~4.7 g/kg in added anchovy sauce sample and 0.4~4.8 and 0~2.4 g/kg in control, respectively. The occurrence of NA such as NDMA and NDEA appeared to arise from the fermented sauce and radish used in preparation of the kimchi.

• Korean Journal of Food Science and Technology
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• v.36 no.2
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• pp.202-210
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• 2004

Doenjang, traditional Korean soybean paste without soysauce and soondoenjang that was not isolated soysauce from soybean paste were thermally processed by the addition of dry anchovy, garlic, red pepper powder and green onion. The volatile flavor components generated from doenjang soup and soondoenjang soup were studied and compared with the change in the various flavors. It was confirmed that some difference of the flavor components was found in two type of soups. Doenjang soup contained a plenty of aldehydes and ketones that revealed the savory flavor. The major flavor components in the soondoenjang soup were sulfur containing compounds that appeared the highest ratio than any other types of flavors and 10 pyrazines. On the sensory evaluation, a great number of pyrazins may be considered as a characteristic of the savory flavor of soondoenjang soup, however, it was not give the reliable result. Stepwise multiple regression analysis of two type of soups indicated that aldehydes, alcohols, ketones were contributory flavor components for overall smell preference and quality preference.

• Journal of Microbiology and Biotechnology
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• v.26 no.6
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• pp.1057-1062
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• 2016

Kimchi is a traditional Korean fermented vegetable food, the production of which involves brining of Korean cabbage, blending with various other ingredients (red pepper powder, garlic, ginger, salt-pickled seafood, etc.), and fermentation. Recently, kimchi has also become popular in the Western world because of its unique taste and beneficial properties such as antioxidant and antimutagenic activities, which are derived from the various raw materials and secondary metabolites of the fermentative microorganisms used during production. Despite these useful activities, analysis of the microbial community present in kimchi has received relatively little attention. The objective of this study was to evaluate the bacterial community structure from the raw materials, additives, and final kimchi product using the culture-independent method. Specifically, polymerase chain reaction-denaturing gradient gel electrophoresis (PCR-DGGE) was used to analyze the 16S rRNA partial sequences of the microflora. One primer set for bacteria, 341F^GC-518R, reliably produced amplicons from kimchi and its raw materials, and these bands were clearly separated on a 35-65% denaturing gradient gel. Overall, 117 16S rRNA fragments were identified by PCR-DGGE analysis. Pediococcus pentosaceus, Leuconostoc citreum, Leuconostoc gelidum, and Leuconostoc mesenteroides were the dominant bacteria in kimchi. The other strains identified were Tetragenococcus, Pseudomonas, Weissella, and uncultured bacterium. Comprehensive analysis of these microorganisms could provide a more detailed understanding of the biologically active components of kimchi and help improve its quality. PCR-DGGE analysis can be successfully applied to a fermented food to detect unculturable or other species.

• Journal of Food Hygiene and Safety
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• v.3 no.4
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• pp.217-223
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• 1988

For the Effective utilization of the fish resources in coastal regions, investigations on preparation of powdered dried arkshell instant soup., quality stability of the products during storage and utilization as a food material were carried out with arkshell, Anadara broughtonii. Three kinds of powdered instant soup were prespared as 0% table salt(A), 5% table salt (B), 15% table salt(C) and packed with vacuum in laminated film bag. (polyester/nylon: 85${mu}ell$/15${mu}ell$, 18$\times$27cm) Their processing conditions and quality stability during storage at room temperature for 90 days were examined. Powdered instant soup was made by washing raw arkshell to remove visceral, clay, sand and blood, hot air drying(60$\pm$1$^{\circ}C$, 20 hrs) after draining and pulverizing dried arkshell to 35 mesh. Powdered instant soup was made by adding 2% sugar 0% table salt (5% and 15% table salt), 10.5% monosodium glutamate, 0.3% black pepper and 0.3% garlic powder to the pulverized dried arkshell. The condition of moisture and water activity of the products were 5.9-6.9% and 0.42-0.43, respectively. The moisture content s , water activity and pH of the products were showed little change and volatile basic nitrogen of them increased slightly during storage. Thiobarbituric acid value increased up to 60 days of storage and then decreased slightly. In solubility, powdered instant soup were showed no remarkable difference comparing with goods on the market. The color value of th products were showed little change during storage, In sensory evaluation, product B were scored slightly higher, in most cased, in flaver, color. taste and overall acceptability comparing with product A or product C during storage. Judiging form the sensory evaluation, powdered instant soup of 5% table salt (B) were the most desirable, and the quality of the products was stable for 90 days at 20$\pm$3$^{\circ}C$.

• Journal of the Korean Society of Food Culture
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• v.10 no.4
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• pp.301-310
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• 1995

The purpose of this study is to survey various recips of the roasted skewered beef (Sanjuk) with twenty three classical cookbooks written before 1943 in Korea. The recipes of the roasted skewered beef are found thirty times in the records, which can be classified into six groups such as the palm-type skewered beef (Sulhamyukjuk), little finger-type skewered beef, mixed skewered beef, juice skewered beef, little finger-type skewered internal organs, and wide-cut skewered internal organs. The palm-type skewered beef and the mixed skewered beef most frequently appeared in the records. The 'Sulhamyukjuk' in the 17th century were inherited while changing its name to 'Sanjuk' in the late 18th century, which is the origin of 'Bulkoki'. There were two types of the roasted skewered beef, the palm-type and the little finger-type; and the palm type preceded the little finger-type. They were used with no change until the 19th century. Actually the roasted skewered beef existed even in the 16th century, but were put down in the early 17th century. In the cooking of 'Sulhamyukjuk' the process of dipping shortly into cold water in the midst of roast seems to absolutely disappeared. Some recipes of the roasted skewered beef were lost, but most have been inherited in the similar way with simplification including little use of internal organs. The main ingredients consisted of parts of cattle such as fresh meat, intestines, heart, liver, omasum, tripe, head, sweet bread, and lung with various vegetables and mushroom. And the main seasonings were mixtures of oil, soy sauce, sesame seed powder, scallion stalk, pepper, sesame seed oil, and salt. And sometimes wine, vinegar, ginger, garlic, and sugar were added.

• Journal of the Korean Society of Food Science and Nutrition
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• v.24 no.1
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• pp.48-53
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• 1995

Changes in the contents of sugar, organic acid, free amino acid and uncleic acid-related compounds of leaf mustard-Kimchi during fermentation at 5~7$^{\circ}C$ were investigated. The leaf mustard-Kimchi was formulated with 4kg leaf mustard, 120g garlic, 80g ginger, 540ml salted anchovies, 1kg green onion, 200g red pepper powder, 200g ground red pepper, 60g whole sesame and 600ml glutinous rice paste. Changes in pH and acidity were relatively slow. Major free sugars were glucose(0.13%) and maltose(0.42%), and residual sugars(0.03-0.04%) were also detected after 32 days of fermentation. Major free amino acids containing more than 26.5mg% were proline, glutamic acid, alanine and histidine. Contents of total free amino acids increased from 244.8 to 397.2mg% by 24 days of fermentation. Of non-volatile organic acid, lactic acid was the most abundant(119.3mg%), and its content increased markedly after 10 days of fermentation. Other organic acids(below 53.1mg%) observed were malic, oxalic and citric acid. Contents of nucleic acid-related compounds were high in the order of hypoxanthine(22.8mg%), IMP(8.3mg%) and GMP(6.9mg%). Hypoxanthine content increased by 10 days(27.3mg%) and decreased thereafter, while the others decreased gradually during the overall period of fermentation.

• Journal of the Korean Society of Food Science and Nutrition
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• v.29 no.5
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• pp.796-801
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• 2000

Kimchi is the Korean traditional food which is fermented properly from salted Korean cabbage of raddish with other various supplements. Kimchi therefore can be the major sources for various kinds of nutrients and other biological substances. The fermentation process accompanies with complicated reaction mechanism which bacteria, fungi and yeast are involved and they produced aroma, taste and bioactive components. To identify nucleoside, this study was conducted with freeze-dried mustard leaf, mustard leaf kimchi and fermented mustard leaf kimchi. Hexane, CH$_2$Cl$_2$, EtOAc and BuOH was used in order to extract their components. The isolated compounds I and II from mustard leaf and mustard leaf kimchi were identified as adenosine and uracil using UV, $^{1}H$-NMR, $^{13}C$-NMR and LC-MS, respectively. Compound I, II and nucleosides are the first report of its occurrence from mustard leaf and their kimchi, the standardized ratios of ingredients for kimchi were 10 of anchovy juice, 8 of red pepper powder, 3 of garlic, 1.5 of ginger, 6 of paste of glutinous rice. The nucleoside of mustard leaf and their kimchi was determined and compared. The order of nucleosides contents of mustard leaf was uridine>cytosine>uracil>adenine>guanosine>guanin, that of fresh mustard leaf kimchi was uridine>uracil>cytosine>guanine>adenosine>adenin>guanosine and that of fermented mustard leaf kimchi (5days at 15$^{\circ}C$) was guanine>adenine>adenosine>guanosine. The differences of nucleoside contents from those were due to various supplements and fermentation process.