• Korean Journal of Environment and Ecology
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• v.24 no.6
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• pp.744-750
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• 2010

This study examined the different polyphenism of larval salamander Hynobius ieechii according to two habitats, pond and stream. We collected salamander's eggs from three regions including Mountain Inwang, Surak and Gwangju. Eggs were treated by four different conditions according to predation level and habitat: high risk - which had a predation risk three times a day; low risk - which had no predation risk, pond and stream habitat. Predation risk was conducted by using chemical cue from Chinese minnows. The chemical cue treatment started from the day of collection and ended one week after the hatching. After the treatment phase, we measured the head width at the level of the eyes(HWE) and the largest head width(LHW) and snout-vent length of the each larva. We calculated the ratio of the head size by dividing HWE by LHW and made a comparison with each of the average ratio of head size according to the predation risk. The results showed that there was a significant difference in the ratio of the head size and snout-vent length according to the predation risk and habitat. From these results we found that predation risk and habitat condition can cause the different polyphenism to the larval salamander and these morphological changes could be affect their mortality.

• Culinary science and hospitality research
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• v.17 no.5
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• pp.231-240
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• 2011

The purpose of this study is to investigate the quality and sensory characteristics of Jiangachi produced with king mushrooms. The moisture content of Jiangachi made from king mushrooms was 72.80% for CON, which was highest, while J4 was 64.46%, which was lowest. In color value results, CON showed the highest L value of 72.80 and J4 showed the lowest value of 31.71. However, the amount of a and b value showed the reverse results. CON showed the lowest sugar content and salinity, whereas J4 showed the highest among the two of them. For PH result, CON and J1 showed the lowest value while J4 showed the highest value of 3.87. According to the results of QDA, J4 showed the strongest brown color intensity, soy sauce flavor, salty taste, and CON showed the weakest of them. CON showed the strongest sweet flavor and sweet taste, whereas J4 showed the weakest. According to the result of acceptance test, CON showed the lowest scent, and for appearance, taste, texture, and overall quality, J3 that contains 25% of soy sauce showed the best results. In conclusion, Jiangachi made with king mushrooms got a high preference when added with soy sauce, and the preference has increased with 25% of soy sauce.

• Food Science and Preservation
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• v.13 no.1
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• pp.95-101
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• 2006

Quality characteristics of Cheongbukjangs with $1\~3\%$ desalted and dried sea tangle powder were investigated after fermentation for 48 hr at $40^{\circ}C$. Addition of sea tangle, irrespective of concentration, did not affect pH and slime content of Cheongbukjang. Color L* and a* values were generally decreased with increasing sea tangle concentration. There were no significant differences in total microbe, amino nitrogen content, and protease and amylase activity between control and Cheongbukjangs with up to $2\%$ sea tangle. However, addition of $3\%$ sea tangle resulted in decreased total microbe, amino nitrogen content, and enzyme activity compared with those of control. Fiber content increased with increasing sea tangle concentration and hardness increased by 1.5 times at $2\%$ sea tangle and by 2.6 times at $3\%$ sea tangle compared with that of control. Results for sensory evaluation revealed that addition of $2\%$ sea tangle was the optimum concentration in view of reducing bitter taste and odor, and improving overall acceptability.

• Food Science and Preservation
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• v.16 no.5
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• pp.623-628
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• 2009

Fresh ginger rhizomes were heat-treated for 10 min, 30 min, or 60 min using hot air ($40^{\circ}C$, $50^{\circ}C$, or $60^{\circ}C$), and stored in low-density polyethylene (0.04 mm thickness) bags for 2 months at $12{\pm}1^{\circ}C$. We studied the effects of heat pretreatment on changes in gas levels after packaging, and quality characteristics of the rhizomes. Oxygen and carbon dioxide levels progressively fell and rose, respectively, as the temperature of heat treatment rose and the duration of such treatment was extended. The sprouting rate of ginger rhizomes treated at $40^{\circ}C$ was higher than that of other samples. Rotting, softening, and increasing pH of rhizomes were accelerated by treatment at higher temperature for a longer time. Weight loss and soluble solid levels were not affected by heat treatment. Sensory qualities such as appearance, odor, and overall acceptability of rhizomes fell with treatment at a higher temperature for a longer time. These results suggest that heat pretreatment has a detrimental effect on the quality of fresh ginger rhizomes.

• Food Science and Preservation
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• v.20 no.2
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• pp.207-214
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• 2013

This study was conducted to investigate changes in the main volatile flavor components of oriental melon during the process of alcohol fermentation via SPME (solid phase micro extraction). The flavor components of oriental melon were shown to have mainly included melon and green flavors. The green flavor was identified to be nonanal, 1-butanol, 1-octen-2-ol and benzene, and its relative concentration was shown to be 16.66%. The nonanal concentration was shown to have been reduced among the green-flavor components, but no significant change in remaining components was observed. Mainly, sweet flavor tended to increase, and the relative concentration of benzene was particularly shown to have increase by 25.58%, accounting for the highest relative concentration. The amount of green-flavor components, except for 1-butanol, was shown to have significantly decrease after alcohol fermentation. Then, no component of green-flavor, which causes an offensive smell, was found during fermentation and aging. Meanwhile, the volatile flavor components, which are consist of acids, were shown to have been produced during alcohol fermentation. In particular, octanoic acid, which causes off-flavor, was shown to be 60.99%, a very high relative concentration during the aging stage. In addition, acetic acid with a pungent sour flavor tended to be produced. A further study on the improvement of flavor in the production of oriental melon wine is required.

• Food Science and Preservation
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• v.20 no.2
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• pp.265-271
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• 2013

The objective of this study was to assess the quality characteristics of yanggaeng prepared with different ratios of blueberry powder: 0%, 3%, 6%, and 9%. The moisture content of the control yanggaeng was lower than that of any other blueberry added groups. The pH decreased while the titratable acidity and the Brix increased as the amount of blueberry powder increased. The lightness (L) and yellowness (b) were the highest while the redness (a) was the lowest in the controls. Texture profile analysis showed that the hardness of the added groups were higher than that of the control which were the lowest. The total polyphenol content and DPPH (2,2-diphenyl-1-picrylhydrazyl) radical scavenging activity increased as the amount of blueberry powder increased. The results of consumer acceptance test revealed that the color preference was the highest in the 9% added group while the smell, taste, texture and the overall acceptability showed no significant differences groups. Based on these results, it is suggested that yanggaeng with up to 9% added blueberry powder can be developed as products without adverse effects on sensory characteristics.

• Food Science and Preservation
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• v.23 no.7
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• pp.945-952
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• 2016

This study was carried out to investigate the quality characteristics and antioxidant activity of Sulgidduk (oriental-style rice cakes) prepared with different amounts (0%, 2%, 4%, or 6%) of maquiberry (Aristotelia chilensis) powder. The moisture content of treated Sulgidduk ranged from 37.75% to 38.79%, with no significant differences between treatment groups. The pH gradually decreased with the increasie in maquiberry powder. The soluble solid content did not show significant differences between groups. The lightness (L) value decreased, while redness (a) value increased with the increase in added maquiberry powder. Hardness of the control group was lower than those of the treatment groups. Consumer acceptance test results revealed no significant differences in smell, taste and overall acceptability scores. The total polyphenol and total anthocyanin contents were 8.66~262.71 mg GAE/100 g amd 0.01~9.76 mg C3G/100 g), respectively. Moreover, the polyphenol and anthocyanin levels increased with increasing levels of added maquiberry powder. In addition. reducing power and 1,1-diphenyl-2-picrylhydrazyl (DPPH) and 2,2'-azino-bis (3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) radical scavenging activities significantly increased with increase in added maquiberry powder. Based on the above results, addition up to 6% maquiberry powder incorporated into Sulgidduk will meet the taste and functional needs for consumers.

• 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.

• Korean Journal of Food Science and Technology
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• v.36 no.2
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• pp.196-201
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• 2004

Volatile components in flower and seed of safflower were identified. Volatile flavor compounds of safflower (Carthamus tinctorius L.) was extracted by simultaneous steam distillation and extraction method using Likens and Nickerson's extraction apparatus. Concentrated extract was analyzed and identified by gas chromatography and GC-mass spectrometry. Main volatile components in flower were terpene compounds, including p-cymene, limonene, ${\alpha}-phellandrene$, ${\gamma}-terpinene$, camphor, 4-terpineol, selinene, ${\beta}-caryophyllene$, torreyol, ${\beta}-eudesmol$, and 10 acids including 3-methylbutanoic acid, 2-methylbutanoic acid, and acids of $C_{2},\;C_{5}-C_{11}$. Main volatile components in seed and safflower were 20 aldehydes including hexanal (7.17%), (E)-2-heptenal (1.10%), (E,Z)-2,4-decadienal and (E,E)-2,4-decadienal.

• Korean Journal of Food Science and Technology
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• v.35 no.2
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• pp.272-279
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• 2003

To determine optimal fermentation period of wild vegetables mixed with black sugar without microorganisms during plant extract fermentation food processing, changes in chemical components, quality characteristics of the fermented broth, and physiological functionality during fermentation period were investigated. pH and $^{\circ}Bx$ of fermented broths decreased gradually during fermentation period. Except persimmon leaf, viscosity of fermented broths of wild vegetables decreased after 3 months fermentation period. Amylase activity increased to $167{\sim}800%$ of its initial level after 6 months fermentation period, and invertase activity decreased by $60{\sim}170$ units after 1 month fermentation. No significant level of cellulase activity was observed. In the sensory evaluation test, inherent flavors and tastes of the wild vegetable decreased during the fermentation period, while those of others gradually increased. Overall acceptability was the highest after 3 months fermentation. Content of total phenolic compounds and electron-donating ability were highest after 3 to 4 months fermentation period, and decreased thereafter. Except Mugwort, tyrosinase inhibitory activity was found in all fermented broths. SOD-like activities were $23.0{\sim}25.1$ and $27.0{\sim}29.2%$ in fermentation broths of acacia flower and persimmon leaf, respectively, and were maintained throughout the fermentation period. Based on these results, fermentation period of 3 to 4 months was determined to be appropriate for plant extract fermentation food processing.