• The Korean Journal of Food And Nutrition
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• v.30 no.4
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• pp.653-664
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• 2017

This study added stevia leaf powder at ratios of 0.5, 1.0, 1.5, and 2.0 percent to Omija-pyun (Schisandra chinensis Jelly) as a natural low-calorie sweetener instead of sugar which is added to Omija-pyun in considerable amounts to evaluate quality characteristics and antioxidant activities compared to the control group with the addition of sugar. Moisture content of Omija-pyun expanded by increasing the measurement of stevia leaf powder (p<0.001), pH (p<0.01) and sugar content (p<0.001) decreased. L-values and b-values revealed a tendency to increase by adding more stevia leaf powder, but a-value revealed a tendency to decrease (p<0.001). Hardness (p<0.001) and chewiness (p<0.05) decreased by adding more stevia leaf powder. Based on the consumer preference evaluation, Omija-pyun with the addition of 0.5 percent stevia leaf powder was the most preferable in terms of color and flavor (p<0.001). The control group and Omija-pyun with the addition of 0.5 percent stevia leaf powder was the most preferable in terms of taste and texture (p<0.001). There were significant differences in the organoleptic properties except hardness between the samples by quantitative descriptive analysis. The control group revealed the highest preference in terms of redness and transparency, and redness and transparency tended to decrease by adding more stevia leaf powder (p<0.001). Organoleptic properties on bitterness and sourness were enhanced by adding more stevia leaf powder in the principal component analysis (PCA). Regarding antioxidant properties, total phenol compounds and flavonoid contents of Omija-pyun increased by adding more stevia leaf powder, and DPPH radical scavenging capacity also increased (p<0.001). Based on results, it is preferable to serve Omija-pyun with the addition of 1.0 percent stevia leaf powder instead of sugar within the context of quality and antioxidant activity.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.17 no.3
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• pp.177-183
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• 1984

This study aims to find the taste compounds of wild loach, Misgurnis mizolepis, which is important fresh-water fish in this country. In order to elucidate the origin of the taste of wild loach meat, free amino acids, organic bases, nucleotides and their related compounds, organic acids, sugars and minerals were analyzed, and then followed by organoleptic test of synthetic extract prepared on the basis of the analytical data. Sensory evaluations of synthetic extracts prepared by omitting each extractive components were carried out by a triangle difference test, and changes in taste profile were assessed. In free amino acid composition, histidine, threonine, glycine, lysine, alanine were abundant. IMP and AMP were dominant in the wild loach in content. Total creatinine and butyric acid were abundant. As for the minerals, $Na^+,\;K^+,\;Cl^-\;and\;PO_4^{3-}$ were found to be the major ions. From the results of omission test of synthetic extracts the major components which contribute to produce the taste were arginine, glutamic acid, valine, aspartic acid, IMP, succinic acid, $Na^+,\;K^+,\;Ca^{2+}\;Mg^{2+}\;Cl^-\;and\;PO_4^{3-}$.

• Korean Journal of Food Science and Technology
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• v.42 no.1
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• pp.45-49
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• 2010

To reduce the astringent taste of lotus root, the effects of various treatment methods such as drying, soaking, steaming and roasting on the physicochemical properties and sensory characteristics were investigated. The following process conditions were selected: 1) drying (D), 2) soaking followed by drying ($SK{\rightarrow}D$), 3) steaming followed by drying ($ST{\rightarrow}D$), 4) drying followed by roasting ($D{\rightarrow}R$), 5) soaking and then drying followed by roasting ($SK{\rightarrow}D{\rightarrow}R$), 6) steaming and then drying followed by roasting ($ST{\rightarrow}D{\rightarrow$}. The tannin content of the lotus root was lowest when it was treated by steaming followed by drying ($ST{\rightarrow}D$). The astringent taste of lotus root was reduced by steaming, and the roasted taste was improved by roasting in terms of sensory and flavor characteristics. Consequently, lotus root treated by steaming and then drying followed by roasting ($ST{\rightarrow}D{\rightarrow}R$) showed the highest preference with respect to astringent and roasted taste.

• Journal of agriculture & life science
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• v.43 no.6
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• pp.95-103
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• 2009

To develop natural intermediate flavoring substances, optimal hydrolysis conditions and taste compounds for two step enzyme hydrolysate(TSEH) using Grass puffer(Takifugu niphobles) were investigated. The optimal conditions for TSEH method were revealed in temperature at $55^{\circ}C$ 3 hour digestion with Alcalase (pH 7.5) at the 1st step and 2 hour at $45^{\circ}C$ digestion with Flavourzyme(pH 6.0~6.5) at the 2nd step. TSEH method was superior to hot-water extraction on the aspect of yield, nitrogen contents and organoleptic taste quality such as umami and control of bitter taste formation. In taste active-components in Glass puffer TSEH, total free amino acid content was 4,502 mg%, major free amino acids were Pro, Leu, Lys, Hypro, Tau, Arg, Phe, Ala, Glu and Val in ordor. As for nucleotides, IMP(372 mg%) was the principal component and also contents of TMAO, total creatinine, and betaine were 43, 278 and 41 mg% in Glass puffer TSEH, respectively. The major inorganic ions in TSEH were Na(949 mg%), K(222 mg%), Cl(1,180 mg%) and $PO_4$(1,081 mg%).

• Korean Journal of Food Science and Technology
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• v.21 no.4
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• pp.583-589
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• 1989

In order to improve the quality and yields of barley tea(water extracts), enzymatic hydrolysis was carried out with using three kinds of mired enzymes of ${\alpha}-amylase,\;{\beta}-amylase$ and protease. The barley treated with enzymes were the crushed , soaked and slightly roasted(light brown) Youngsanbori(hulless) and the physical, chemical and sensory characteristics were investigated. The results showed that enzymatic hydrolysis caused a signigicant increase in solid yields (80%) of barley tea, particularly with the mixed enzyme 5,000 which has higher activity of ${\alpha}-amylase$ than the other enzymes. The intrinsic viscosity of barley tea was reduced by enzymatic hydrolysis as the value of dextrose equivalent increased The Hunter L, a, b values was lower for the enzyme treated barley tea but showed not significant difference with reaction time. The organoleptic evaluation clearly showed that both intensity and acceptability of odor and taste was markedly Increased. The roasted nutty, and sweety odor and taste were particular in increase by mixed enzyme 5,000.

• Journal of Microbiology and Biotechnology
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• v.27 no.10
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• pp.1736-1743
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• 2017

Sourdough is made by fermentation of dough by lactic acid bacteria (LAB) and yeast to improve bread properties like volume, flavor, and texture. A Korean traditional sourdough was made by fermenting rice flour with rice wine (makgeolli) and used to make sponge-like bread (jeung-pyun). The aim of this study was to investigate the microbial diversity of makgeolli products and their influence on the organoleptic quality of jeung-pyun. Three commercial makgeolli were tested for jeung-pyun production, with each product exhibiting varied dough swelling rates and organoleptic qualities, and among them, J-product was ranked highest in texture and taste. Microbial analysis of the three makgeolli also showed a big difference in their population and diversity. J-product had the highest LAB and yeast counts, and the predominant species were Lactobacillus casei, Lactobacillus brevis, Leuconostoc pseudomenteroides, and Saccharomyces cerevisiae. Using J-product, sourdough was fermented at $25^{\circ}C$, $30^{\circ}C$, and $35^{\circ}C$, and the microbial growth in and textural properties of jeung-pyun were examined by instrumental and sensory tests. At high temperature ($35^{\circ}C$), the rates of dough swelling and acidification were fast due to rapid microbial growth mainly caused by LAB, resulting in a short leavening time and soft and sour jeung-pyun. Sensory tests showed consumer preference for the soft and mild-sour jeung-pyun. This study shows that LAB in makgeolli play key roles in production of jeung-pyun, influencing the textural and sensory properties. For the production of high-quality jeung-pyun, development of LAB starters with high gas productivity and low acidity and establishment of an optimal fermentation procedure for rice dough are necessary.

• Korean Journal of Food Science and Technology
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• v.22 no.4
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• pp.439-444
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• 1990

Fourteen varieties of soybeans grown in Korea were investigated for their chemical composition, yields and organoleptic properties of soybean curd. The soybean curd was prepared by soaking, grinding and heating of soybeans followed by filtration, coagulation with $CaSO_4$ and pressing. The proximate analysis showed that soybean curd had the moisture content of $75.0{\sim}82.0%\;and\;48.6{\sim}56.1%\;protein,\;14.8{\sim}40.4%\;lipids\;and\;6.4{\sim}26.8%$ carbohydrate by dry weight basis. The yield of volume total solids and protein from 100g of soybeans were $182.2{\sim}227.5cm^3,\;42.65{\sim}55.60%\;and\; 57.90{\sim}76.50%$, respectively. Among the 14 varieties, the highest volume yield was obtained from Suwon-141 which has the highest contents of moisture, carbohydrate and the lowest in lipids of soybean curd. The curd prepared with Baegun and Jangyeob contained relatively low values in moisture, protein and carbohydrate and yielded the lowest in volume yield. Therefor moisture, protein and carbohydrate contents in soybean curd affected greatly on volume yield. The organoleptic properties of odor and taste couldn't find any significant relationship with chemical composition of soybean curd eventhough there were some difference in their intensities among varieties.

• The Korean Journal of Food And Nutrition
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• v.8 no.3
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• pp.199-205
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• 1995

The study was carried out to compare the factors of overall preference In the sensory test to the analyzation of some compositions in the 7 kinds of old grasses : An Evening Primerose, a Spiderworts, the flower of a Convolvulus, So Ru Jang Yl, Shoe Bl Rum.O Yi Pul, Jip Sean Na Mul. Results were summaries as follows. 1. The Tannin contents of fresh sample and cooked samples were determined as 0.27~2.4g%, 0.25~1.439% respectively. The largest amount of fresh samples was contained In a Shoe Bi Rum. The smallest amount of them was in an Evening Primerose. The highest level of cooked samples was found in a Shoe Bi Rm, and the lowest was in the O Yi Pul. These results were similar to sensory test. 2. The free amino acid contents of 2 kinds of samples were determined as 25.15~179.5mg%, 1.86~13. 6mg% respectively. The largest amount of sweet taste of them was 0 Yi Pul and So Ru Jaeng Yl respectively. But So Ru Jaeng Yi is not appeared sweety becase this have much tannin. The smallest amount of sweet taste was a Spiderwort. The highest level of bitter taste was So Ru Jaeng Yl the and lowest was Jip Sean Na Mul. Among of them Jlp Sean Na Mul is similar to organoleptic test but So Ru Jaeng Yi is not strong bitter taste in sensory evaluation. The highest level of sour taste of cooked samples was So Ru Jaeng Yi and the lowest of them was Shoe Bi Rum. The reducing sugar contents of fresh sample and cooked samples were determined as 1.80~ 4.9g%, 1.84 ~3.579% respectively. The largest of fresh samples were So Ru Jaeng Yl and the lowest was Shoe Bi Rum. The highest of cooked samples were an Evening Primerose and the lowest was a Convolvulus. Among of these results an Evening Primerose was not similar to sensory test because it has much other components. The level of chlorophyll of fresh samples and cooked samples were determined as 11.7~39mg%, 11.3~40.3mg% respectively. The highest of fresh samples was Shoe Bl Rum and the lowest was J ip Sean Na Mul. The largest of cooked samples was So Ru Jaeng Yi and the lowest was a Jlp Seu Na Mul.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.17 no.1
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• pp.33-39
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• 1984

In order to elucidate the taste compounds of wild eel, Anguilla japonica, free amino acids, nucleotides and their related compounds, organic bases, sugars, organic acids and minerals were analyzed, and then followed by organoleptic test of synthetic extract prepared on the basis of the analytical data. Taste panel assessments of synthetic extracts prepared with each extractive component omitted were carried out by a triangle difference test, and changes in profile were assessed. In free amino acid composition, lysine was dominant occupying $25\%$ of total free amino acid. The other abundant amino acids were glycine, arginine, alanine and histidine. From the results of analysis of nucleotides, IMP was dominant showing about $70\%$ of total nucleotides while ATP, ADP, AMP, inosine and hypoxanthine were low in content. Among organic bases total creatinine was abundant. The amount of betaine was 24 mg/100 g. The main organic acid were butyric acid, valeric acid and succinic acid. As for the sugars, glucose and inositol were 1-2 mg/ 100g in content. $K^+,\;Na^+,\;PO_{4}^{3-}\;and\;Cl^-$ were found to be the major ions. From the results of omission test the major components which contribute to produce the taste were glycine, serine, glutamic acid, IMP, $Na^+,\;K^+,\;Cl^-,\;PO_{4}^{3-}$, lysine, alanine, isoleucine, aspartic acid and creatinine.

• Culinary science and hospitality research
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• v.21 no.6
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• pp.195-205
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• 2015

This study was conducted to investigate the chemical characteristics of different treatments of Gochujang during fermentation at $28^{\circ}C$ C for 100 days, in an effort to improve its taste and organoleptic quality. All treatments of Gochujang saw no effects on total viable bacterial numbers, which kept constant level, during fermentation (2.7~3.22 log CFU/g). Yeast numbers did not change for all treatments in the 100 days of fermentation, but then decreased thereafter, yeast numbers increased during fermentation, showing a level of 0.45~0.42 mg% in the Gochujang with red chilli seed powder on the 100th day of fermentation. DPPH radical scavenging in the early stage of fermentation revealeda tendency to increase in conjunction with an increase in the amount of red chilli seed powder added. Sensory examinations, including taste and preference, of the manufactured Gochujang suggest that the optimal fermentation product results from the condition of 20% added red chilli seed powder.