• Applied Biological Chemistry
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• v.50 no.4
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• pp.281-286
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• 2007

The effects of green tea powder (GTP) on kimchi quality were evaluated by investigating acid production, growth of lactic acid bacteria, sensory properties, and several volatile odor components of GTP-added kimchi. The concentrations of GTE added to kimchi were 0.2, 0.4, 0.6 and 1.2% (w/w) of salted Chinese cabbage. The pH of kimchi with higher amounts of added GTP increased with ripening. The acidity of unripened kimchi or kimchi ripened for one day generally increased with the addition of GTP, while that of kimchi ripened for two or three days generally decreased with the addition of GTP. Addition of GTP had no significant effect on the lactic acid bacterial count of kimchi. Scores of overall acceptability, taste and odor of 0.2 or 0.4% GTP-added kimchi were higher than those of other samples, whereas scores of color decreased with increasing amount of GTP added to kimchi. Texture of kimchi added with higher amounts of GTP and ripened for two or three days resulted in lower score than the reference sample. Diallyl sulfide and methyl trisulfide were newly produced with the ripening of kimchi, and the amounts of some volatile odor components in kimchi were changed during ripening.

• Korean Journal of Food Science and Technology
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• v.35 no.5
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• pp.937-942
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• 2003

Kimchi was prepared with 5, 10 or 20%(w/v) Chinese radish and ripened at $20^{\circ}C$ for 3 days. Acid production and growth of lactic acid bacteria, sensory properties, and several volatile odor components in kimchi were examined. The effects of freeze-drying on the quality of kimchi were also studied. The pH of the control (kimchi prepared without Chinese radish) was 4.31 and gradually decreased as the amount of Chinese radish increased. The acidity of the control was 0.673% and gradually increased as the amount of Chinese radish increased. Viable counts of lactic acid bacteria in the samples did not differ significantly from the control. The pH of freeze-dried/rehydrated kimchi slightly decreased as the amount of Chinese radish increased while its acidity gradually increased. The viable count of lactic acid bacteria of freeze-dried/rehydrated kimchi did not differ significantly as the amount of Chinese radish increased. Overall acceptability and taste of kimchi and freeze-dried/rehydrated kimchi generally improved by the addition of 10% or 20% Chinese radish. Six volatile odor components including ethanol and five sulfur-containing components (SCC) were identified from unripened kimchi, and the level of two SCCs increased as the amount of Chinese radish increased. Eight volatile odor components, ethanol and seven SCCs, were identified from ripened kimchi and the level of five SCCs increased as the amount of Chinese radish increased. Diallyl sulfide and methyl trisulfide were newly detected from the ripened samples, but not from the unripened kimchi. Freeze-drying substantially reduced all of the volatile odor components from kimchi. Five volatile odor components including ethanol and four SCCs were identified from the freeze-dried/dehydrated samples.

• Korean journal of food and cookery science
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• v.22 no.5 s.95
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• pp.609-616
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• 2006

The effects of purified licorice (Glycyrrhiza uralensis) extract (PLE) as a sugar substitute on kimchi quality were evaluated by investigating acid formation, growth of lactic acid bacteria, sensory properties, and volatile odor components of PLE-added kimchi. The pH of kimchi with higher amounts of added PLE increased slightly with two or three days ripening. The acidity of unripened kimchi or kimchi ripened for one day significantly increased with addition of PLE, while that of kimchi ripened for two or three days decreased significantly (p<0.05). Addition of PLE had no significant effect on the lactic acid bacteria count of kimchi compared to that of sugar. Overall acceptability and taste of 0.005 or 0.01% PLE-added kimchi ripened for two to three days were higher than those of other samples, whereas addition of more than 0.01% PLE to kimchi unripened or ripened for one day resulted in lower overall acceptability and taste than the reference sample. Diallyl sulfide and methyl trisulfide were newly produced by ripening of kimchi, and the amounts of some volatile odor components in kimchi were also changed during ripening.

• Korean Journal of Food Science and Technology
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• v.32 no.1
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• pp.102-110
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• 2000

Peeled garlic was stored at $-18^{\circ}C\;and\;-40^{\circ}C$, respectively and changes in main quality factors during storage were determined for $15{\sim}16$ months. The puncture force measured by texturemeter was $2709{\pm}368$ G.S at the beginning of storage and did not change significantly after the 15 months storage. Drip losses of stored garlic were 0.4% and 0.7% at $-18^{\circ}C\;and\;-40^{\circ}C$, respectively. Major flavor compounds of garlic analyzed by GC and GC/MS, such as diallyl disulfide, 1,3-dithiane, diallyl sulfide, 2-butanal, were not changed in their quantity during the frozen storage. The contents of cysteine, valine and tyrosine increased slightly notwithstanding the storage temperature. Sucrose content slightly decreased, but glucose and fructose tended to increase in garlic stored at $-18^{\circ}C$. The content of pyruvic acid, degradation product of alliin, did not change during storage at both storage temperatures. These results indicated that peeled garlic could be stored at $-18^{\circ}C$ for longer than 15 months without quality problems.

• Journal of the East Asian Society of Dietary Life
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• v.22 no.4
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• pp.506-513
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• 2012

This principal objective of this study was to evaluate the sensory properties and flavor compounds of Kimchi prepared with different levels (0.0%, 0.4%, 0.8%, and 1.2%) of Backryeoncho extracts (BE). At high levels of BE, Kimchi showed increased level of crispness and flavor, and also jeotgal odor decreased in the sensory evaluation. Addition of 0.8 % BE resulted in the highest scores for color, taste, and overall acceptance of Kimchi. Therefore, addition of 0.8 % BE appears to be an acceptable approach to enhance the quality of Kimchi without reducing acceptability. As a result of flavor compound analysis, a total of 24 volatile flavor compound, including 11 S-containing compounds, 6 terpenes, 1 acid, 1 ester, 1 alcohol, 2 miscellaneous compounds, 2 thiocyanates, etc., were detected by GC/MS. The major volatile compounds were s-containing compounds and terpene hydrocarbon, and especially terpene of sabinene was newly detected in Kimchi with added BE. Levels of 2-vinyl-[4H]-1,3-dithin derived from garlic flavor as a sulfide-containing compound along with diallyl trisulfide derived from green onion flavor were reduced in Kimchi with added 0.8% BE. Most sulfide-containing compounds were reduced in Kimchi with added BE, whereas most terpenes detected in control Kimchi were not detected.

• Journal of the Korean Society of Food Science and Nutrition
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• v.45 no.10
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• pp.1438-1446
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• 2016

The objectives of this study were to investigate the effects of superheated steam (SHS) treatment on the physicochemical and microbial properties of garlic. The garlic was treated by SHS at temperatures of 100, 150, 200, 250, 300, and $350^{\circ}C$ for 60 s. The moisture content of raw garlic was lower than that of SHS-treated garlic. The total thiosulfinate and pyruvate contents were dramatically reduced by SHS treatments. The antioxidant activities of garlic measured by ferric reducing/antioxidant power, 2,2-azinobis(3-ethylbenzothiazoline-6-sulfonic acid) diammonium salt radical scavenging assay, and total phenolics content decreased by SHS. The major volatile sulfur compounds of garlic such as diallyl disulfide, allicin, allyl sulfide, diallyl sulfide, and diallyl trisulfide were significantly reduced by SHS. The antimicrobial effects of raw garlic were stronger than those of SHS-treated garlic against three strains of bacteria, including Staphylococcus aureus, Escherichia coli, and Bacillus cereus. However, total aerobic bacteria in garlic were dramatically reduced by SHS from 8.6 to 2.9 log CFU/g. The results from the sensory evaluation show that SHS treatment of garlic above $200^{\circ}C$ provides better acceptably due to reduction of off-flavor and pungency of garlic. These results suggest that superheated steam treatment can used as an efficient process for reducing garlic off-flavor and pungency.

• Korean Journal of Soil Science and Fertilizer
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• v.21 no.2
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• pp.183-193
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• 1988

The relationship between the sulfur fertilization, and the quality and yield of garlic was investigated. The garlic was grown in pot and field at the five fertilization levels of sulfur. The growth characteristics, yield and flavour components of the garlic were studied. The results were summarized as follows; 1. The sulfur applications contributed to a weight and yield of the bulb in SP-10 (10kg/10a) and SF-20 (20kg/10a) significantly, respectively. 2. From the volatile oil obtained by steam distillation of garlic, fourteen organie sulfur components were separated, identified and quantified by GC and GC/MASS and the SP-10 and SF-20 were higher in the concentration of the flavour components in the volatile oil than other treatments. 3. It is considered that the organic sulfur components were synthesized in the top and transported to the bulb of the garlic. 4. In conclusion, SF-20, 20kg/sulfur per 10a, could be recommended to get maximum yield and a good quality of garlic in view of evaluation through the contents of organic sulfur components in the volatile oil and the yield of the bulb.

• Natural Product Sciences
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• v.11 no.2
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• pp.67-74
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• 2005

The ethanolic extracts of the leaves and bulbs of Allium victorialis var. platyphyllum (Liliaceae) collected from Daegwallyoung (D) and Ullung Island (U) in Korea were obtained using three different extracting methods. The first extracts, DL-1 DB-1, UL-1 and UB-1, were obtained from leaves (L) and bulbs (B) dried at $90^{\circ}C$, respectively, and the second extracts, DL-2, DB-2, UL-2 and UB-2, were obtained by extracting the leaves and bulbs of fresh plant parts. The third extracts DL-3, DB-3, UL-3 and UB-3 were obtained by incubating leaves and bulbs at $36^{\circ}C$. The six extracts obtained from A. victorialis var. platyphyllum at Daegwanllyoung (cultivated site) were orally administered to examine for a possible antihepatotoxic effect in $CCl_4-induced$ rats. DL-1 exhibited the most pronounced effect. The extracts inhibited serum ALT, AST, SDH, ${\gamma}-GT$, ALP and LDH activities elevated by $CCl_4$ injection and attenuated decreased glutathione S-transferase, glutatione reductase and ${\gamma}-glutamylcysteine$ synthetase activities and a decreased hepatic glutathione. However, the extracts obtained from Ullung Is. (native site) were less active than the extracts from Daegwallyoung, suggesting that A. victorialis var. platyphyllum from the cultivated site is more useful for functional food than of native site. These results also suggest that the antihepatotoxic effect is due to a higher content of hepatic glutathione. Gas chromatography of the twelve extracts showed significantly different sulfides, disulfides or trisulfides contents belonging to volatile sulfur substances (VSS). Nine components were identified on the basis of their mass spectra, namely, dimethyl disulfide, dimethyl trisulfide, diallyl disulfide, dipropyl disulfide, allyl methyl sulfide, allyl methyl trisulfide, 2-vinyl-4H-1,3-dithiin, 3,4-dihydro-3-vinyl-1,2-dithiin, and allithiamine. Extract DL-1 had the highest VSS content. Dried plant materials contained larger amounts of the VSSs than other extracts, and the leaves contained larger amount than the bulbs. These results suggest that heat treatment increases the antiheaptotoxic ability of A. victorialis var. platyphyllum by increasing the proportion of VSSs.