• Journal of the Korean earth science society
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• v.22 no.1
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• pp.10-19
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• 2001

There are three scoria cones and their eruptive materials in Sarabong-Byeoldobong-Hwabukbong area Cheju Island. And they made complicated volcanic stratigraphy. In Byeoldobong tuff, basalt and granite xenoliths are present. It is presumed that the granite is a kind of basement of Cheju island. And Biseokgeori hawaiite has many kaersutite phenocrysts. Therefore, this area is very important for the study about history of volcanic activity of Cheju island. The lowest beds are Shinheung basalt and Byeoldobong tuff. Byeoldobong tuff has xenoliths of granite and phenocrystalline basalt. After the formation of these rocks, the Hwabukbong volcanism commenced. First of all this volcanism formed Biseokgeori hawaiite that has lots of kaersutite, a member of amphibole group, characteristically. Over this rock, Hwabukbong scoria cone was formed. The next Sarabong volcanism effused Keonipdong hawaiite that has lots of plagioclase and olivine phenocrysts and then Sarabong scoria cone was made up. Basalt xenolith in Byeoldobong tuff is different from Shinheungri basalt with regard to petrography, therefore this offers suggestion about existence of another basalt between basement and Shinheungri basalt. Granite xenolith derived from the basement of this area has features of the Jurassic granite in the Korea Peninsula, for example a lot of myrmekitic texture, microcline, and absolute age (172.4 Ma) by K-Ar method.

• Culinary science and hospitality research
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• v.20 no.4
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• pp.127-143
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• 2014

This study investigated color barley powder substituted for wheat flour in bread recipes with the amounts of 0%, 5%, 10%, 15% and 20%. Color barley powder consisted of 9.35% of moisture content, 9.37% of crude protein, 1.64% of crude fat and 2.96% of crude ash. Water soluble dietary fiber is 3.21, insoluble dietary fiber is 4.91, total dietary fiber content is 8.12, and ${\beta}$-glucan is 49.31. DPPH radical scavenging activity is 56.76%, total phenol content is 234.34. The farinograph measurement result of the bread made with color barley powder showed that consistency, water absorption, development time and time breakdown have decreased. The alveogram measurement result of the bread made with color barley powder showed that overpressure, extensibility, swelling index and deformation energy have increased. The amylograph measurement result of the bread made with color barley powder showed that peak viscosity, hot past viscosity and breakdown have decreased. Baking loss and specific loaf volume have decreased as the color barley powder content increased. The chromaticity measurement result showed that the 'L' and 'b' of bread have increased as the color barley powder content increased, while the chromatic 'a' value increased. The texture measurement result showed that the hardness and gumminess of bread have increased as the color barley powder content increased. cohesiveness, springiness and chewiness have decreased. Overall preference scores showed a high overall acceptability for the bread made with 10% color barley powder.

• Journal of the Korean Society of Food Science and Nutrition
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• v.42 no.6
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• pp.948-956
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• 2013

This study investigated methods to improve the quality of Topokkidduk using grapefruit seed extracts and acid regulation agents. Topokkidduk was investigated in terms of its moisture, color, pH, texture, microbial composition, and sensory properties. The moisture content of Topokkidduk was highest for Topokkidduk supplemented with grapefruit seed extracts. The color of Topokkidduk (the L value) decreased, whereas the "a" value increased with the addition of grapefruit seed extracts. The texture of Topokkidduk was affected more by additives than storage temperature. The addition of grapefruit seed extracts and acid regulation agents were effective for the inhibition of microbial activity in Topokkidduk during storage. The overall acceptability values of Topokkidduk (without supplements) were highest among the samples. These results suggest that grapefruit seed extracts and acid regulation agents can be used to control microbial load and moisture levels in Topokkidduk.

• Journal of the Korean Society of Food Science and Nutrition
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• v.42 no.8
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• pp.1220-1226
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• 2013

The objective of this study is to investigate the quality characteristics and antioxidant activities of yanggaeng prepared with different amounts of aronia juice. Aronia juice was incorporated into yanggaeng at different levels (containing 50, 100, and 150 g of aronia juice in AJ 50, AJ 100, and AJ 150, respectively) based on the total weight of water. Total acidity and sugar contents showed a significant increase, however, pH showed a decrease with increasing levels of aronia juice. Hardness also showed an increase with increasing levels of aronia juice. Regarding texture profile analysis, hardness, springiness, and chewiness of yanggaeng were increased, however, cohesiveness was similar compared to the control and aronia juice added treatments. In chromaticity determination, L and b values showed a decrease, however, a value increased with increasing levels of aronia juice. The total polyphenols, flavonoids, and anthocyanin contents were increased proportionally with increasing levels of aronia juice. Antioxidant activity measured by DPPH and ABTS radical scavenging activities were significantly higher than those of control and increased proportionally according to the concentration of aronia juice. The sensory evaluation indicated that AJ 100 showed the best preference in color, taste, texture, flavor, and overall acceptance. These results suggest that aronia juice may be a useful ingredient in yanggaeng for improvement of quality and antioxidant potential.

• Journal of the Korean Society of Food Science and Nutrition
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• v.42 no.8
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• pp.1283-1289
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• 2013

This study was conducted in order to evaluate the effect of black garlic extract on quality characteristics of white pan bread. White pan bread contained black garlic extract at levels of 0%, 5%, 10%, and 15% based on flour. Analysis of volume and specific loaf volume, water activity, texture, crumb color, and sensory evaluation of white pan bread were performed. As the amount of black garlic extract increased, volume and specific loaf volume decreased. Hardness, Max. G (maximum gram), gumminess, and cohesiveness by texture analyser showed a higher value in treatment, however, in hardness, no differences were observed between control and treatment with addition of 5% black garlic extract. In crumb color analysis, as the amount of black garlic extract increased, L value decreased and values for a and b increased. On sensory evaluation, no differences were observed between control and treatment containing 5% black garlic extract, however, addition of more than 10% resulted in lower scores. As a result of this study, 5% black garlic extract was considered a reasonable level for preparation of a health promoting white pan bread.

• Journal of Mushroom
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• v.16 no.3
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• pp.131-139
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• 2018

The king oyster mushroom (Pleurotus eryngii) is widely consumed because of its flavor, texture, and its functional properties such as antioxidant activity and prebiotic effects. However, long-term product storage and transportation (e.g., export) are difficult because of its limited durability. The shelf-life of king oyster mushroom is affected by environmental factors such as temperature, humidity, gas composition, and ventilation, which may affect sensory characteristics including respiration rate, texture, moisture, flavor, color, and pH. The major problems regarding storage of mushrooms are browning, flavor changes, and softening. To address these problems, novel preservation techniques were developed, and more durable variants were bred. Different drying methods, gamma irradiation, chitosan coating, modified atmosphere (MA) packaging, and controlled atmosphere (CA) storage were evaluated in order to extend the shelf-life of king oyster mushrooms. Freeze drying showed better results for the preservation of mushrooms than other drying methods. Irradiation with 1 kGy was more effective for extending mushroom shelf-life than higher doses. The preservative performance of chitosan-based films was improved by combining the compound with other hydrocolloids, such as oil, protocatechuic acid, and wax. The CA storage conditions recommended for king oyster mushrooms are 5kPa $O_2$ and 10 to 15kPa $CO_2$ at temperatures below $10^{\circ}C$. Active MA packaging with microperforated PP film was also effective for maintaining quality during storage.

• Journal of Food Hygiene and Safety
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• v.12 no.1
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• pp.26-38
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• 1997

The quality changes of hams and sausages in refrigerated storage were investigated. Seven types of hams and six types of sausages produced in Korea were collected from markets and stored at 1$0^{\circ}C$ according to the Food Code of Korea, and then chemical, microbiological, textural and sensory characteristics were evaluated at 30, 40 and 50 days. The proximal analysis showed considerable variation in fat with less variation in moisture and protein. The pH values of hams and sausages slightly changed with no consistent difference. Water activity values of all samples except one type of sausage were consistent over time in refrigerated storage. No purge losses of hams were observed except two types of samples in the intial stage. Several types of sausages showed purge losses with no consistency and one type of sausage showed consistent purge losses (0.44~11.29%) during the storage. The volatile basic nitrogen (VBN) content of hams and sausages was still within 20 mg% (Standard and Specification of Korea) on the 50th day, although the VBN of all samples significantly increased over time (p<0.05). The thiobarbituric acid (TBA) values of hams and sausages were well below 1.0 during the storage, although the TBA values of all samples significantly increased (p<0.05). However it was noticed that one type of ham and two types of sausages showed TBA values of 0.945, 0.928 and 0.978, respectively. All the standard plate counts (SPCs) of hams during the storage period showed a level below 30 CFU/g except one type of sample with 103 CFU/g at 50 days. All the SPCs of sausages showed a level below 50 CFU/g except one type of sample with 102 CFU/g and two types of samples with 104 CFU/g on the 50th day. Coliform groups were not counted in all samples during the storage. Instrumental texture analysis showed that springiness, cohesiveness, chewiness, gumminess and adhesiveness slightly changed with no consistent difference. The hardness of the hams showed a decreasing tendency, and the hardness of the sausages an increasing tendency with no significant difference. Sensory evaluation for color, flavor, taste, texture and overall acceptability showed decreasing tendencies over time (p<0.05). The scores of the five sensory characteristics maintained the medium level of quality at the termination of the experiment. Although the results indicated that the ham and sausage samples were acceptable after the 50 days' storage at 1$0^{\circ}C$, the shelf-life of the samples should be determined considering the rapid growth of bacteria and the high TBA values at 50 days.

• Food Science of Animal Resources
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• v.27 no.1
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• pp.16-21
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• 2007

Twenty pork loins were processed for manufacturing raw hams according to a short-ripening procedure including dry-and wet-curing for 1 week each, followed by ripening for 2 weeks. Raw ham cuts were vacuum-packaged and stored in darkness at 10 and $25^{\circ}C$ for 90 days, and their physicochemical and sensory quality characteristics were investigated. The sodium chloride content of raw hams stored at 10 and $25^{\circ}C$ was maintained at approximately 5.1% throughout storage at either temperature. No significant changes in water, crude protein, crude fat and ash contents were observed in all samples regardless of storage temperature and storage length. Thiobarbituric acid and volatile basic nitrogen values increased continuously during the storage period. The changes in physicochemical characteristics including pH, water activity texture lipid oxidation and protein degradation, and sensory attributes appeared to be more pronounced at $25^{\circ}C$ than at $10^{\circ}C$ over the storage period. At prolonged storage periods, a significant quality loss in the aspect of texture changes including hardness, brittleness, elasticity, cohesiveness, gumminess, and adhesiveness was observed (p<0.05). Based on sensory evaluation scores, It appeared that vacuum-packaged raw ham cuts stored at 10 and $25^{\circ}C$ were not acceptable after 75 and 45 days, respectively.

• Journal of the Korean Society of Food Science and Nutrition
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• v.43 no.12
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• pp.1896-1905
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• 2014

The purpose of this study was to manufacture white bread by substituting bakery yeast with natural starter. The general composition of wild grape, was 81.22% moisture, 0.81% ash, 0.74% crude fat, 1.58% crude protein, and 15.65% carbohydrate contents. Fermented wild grape extract was made by culturing for 4 days at $25^{\circ}C$. Flour was added three times to fermented wild grape extract and incubated for 36 hours at $20^{\circ}C$ to manufacture sourdough. We investigated the quality characteristics of white bread with different amounts of fermented wild grape sourdough. The pH of dough decreased with increasing amounts of sourdough, whereas total titratable acidity of dough significantly increased. Fermentation power of dough expansion significantly increased with increasing incubation time, and control showed the highest value of 126.67%. White bread specific volume was highest in, 50% sourdough at 4.76 mL/g. Water content increased with increasing amounts of sourdough, whereas water activity was not significantly different between the samples. For texture, hardness of 50% sourdough was lowest at 19.23 g. In the sensory evaluation, color, flavor, softness and overall acceptability decreased with increasing amounts of sourdough. As a result, 50% sourdough can be considered as a baker's yeast substitute for making natural fermented bread.

• Culinary science and hospitality research
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• v.21 no.4
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• pp.207-220
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• 2015

The purpose of this study was to evaluate the quality properties of muffins added with different concentrations(0, 3, 6, 9, and 12%) of wheat sprout powder. The height of muffins were decreased by the addition of wheat sprout powder. The weight and the baking loss rate of muffins were not significantly different among all sample groups. The volume and specific loaf volume of muffins were decreased by the addition of wheat sprout powder. The moisture content of the samples with wheat sprout powder was higher, but the pH of muffins was lower than those of the control group. DPPH radical scavenging activity of the control group was 18.17%, whereas the samples with wheat sprout powder ranged from 21.13~34.67%. In color of crumb, the L and a value were decreased, but the b value was increased significantly by the addition of wheat sprout powder. The hardness and brittleness of textural properties of muffins were not significantly different between control and groups with 3%, 6%, and 9% of wheat sprout powder. Sensory evaluation scores in terms of after swallowing, appearance, flavor, taste, texture and overall preference of groups with 3% and 6% of wheat sprout powder did not show any significant difference or were higher when compared to the control group. Result indicated that the optimal concentration of wheat sprout powder into the muffin formula was 6%(w/w).