• Korean Journal of Food Science and Technology
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• v.40 no.6
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• pp.626-632
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• 2008

In an effort to improve the quality and palatability of kochujang, the physicochemical and microbial characteristics of kochujang were assessed when different quantities of citrus concentrate were added during fermentation. The moisture content of kochujang increased throughout the entire fermentation process. The pH of kochujang was reduced gradually, but the titratable acidity was increased to 10 weeks of fermentation. The amino-nitrogen and reducing sugar contents of kochujang to which citrus concentrate was added were higher than those of the control, and these values increased with increasing fermentation time. As the ratio of added citrus concentrate increased, the color of the kochujang brightened. The total cell and yeast counts were unaffected by the addition of citrus concentrate. Our sensory evaluation test showed that the addition of 6% citrus concentrate was the optimal condition for improving the quality of kochujang. In conclusion, the addition of citrus concentrate was desirable for the improvement of the quality and palatability of kochujang.

• Korean Journal of Food Science and Technology
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• v.45 no.3
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• pp.267-273
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• 2013

We aimed to improve the flavor quality of plain yogurt, which is known to be sour and less desirable in flavor, varying concentrations of a buckwheat saccharification solution (BSS) were added to milk, followed by fermentation with commercially available mixed strains of lactic acid bacteria. Volatile compounds were analyzed using the gas chromatography-headspace-solid phase microextraction (GC-HS-SPME) method. Fermentation properties, including pH, titratable acidity, viable cells, viscosity, and color value were also measured. Eleven volatile compounds were identified with GC-MS. Of which, diacetyl, butanoic acid, and 2-heptanone proportionally increased as the levels of BSS increased. Undesirable compounds such as acetic acid and 2-butanone, decreased as BSS concentration increased. Fermentation properties were significantly altered with the addition of BSS. Our findings indicate that the flavor quality of plain yogurt can be improved by adding BSS for fermentation, with an additional health benefit from buckwheat.

• Korean Journal of Food Science and Technology
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• v.50 no.2
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• pp.179-185
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• 2018

In this study, the optimal fermenting conditions of sugar extracts of Artemisia annua L. (Aa), Houttuynia cordata Thunb (Hc), and Saururus chinensis Baill (Sc) were determined to develop fermented beverages. The sugar extracts ($50{\pm}5^{\circ}Bx$) were diluted to 10, 15, and $20^{\circ}Bx$, and fermented with 2% (v/v) of Lactobacillus plantarum DK119 ($5{\times}10^9CFU/mL$) at $37^{\circ}C$ for 4 days. According to the lactic acid bacteria population, pH, titratable acidity, and reducing sugar content, $20^{\circ}Bx$ for Aa, $10^{\circ}Bx$ for Hc and $15^{\circ}Bx$ for Sc were the maximum concentrations for the fermentation. There were no changes in total polyphenol content in the extracts of Aa, Hc, and Sc, whereas the radical scavenging activity and ferric reducing antioxidant power were increased during the fermentation. Lactic acid fermentation resulted in improvement of sensory evaluation scores on unfavorable plant taste and overall acceptability of the sugar extracts of medicinal plants.

• Horticultural Science & Technology
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• v.32 no.6
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• pp.912-916
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• 2014

Japanese apricot (Prunus mume Siebold and Zucc.) is a deciduous tree of the family Rosaceae, and it has long been used as a folk remedy for cough and dyspepsia. A new cultivar 'Okjoo' was developed from a cross between 'Gyokuei' and 'Rinsyu' carried out at the National Institute of Horticultural & Herbal Science in 1993. It w as s elected for good shape, large size and high yield capacity in 2006, and then it was granted official patent No. 4556 in 2013. It blooms 4 days and 2 days earlier than 'Gyokuei' and 'Rinsyu', respectively. Its flower petal color is pink, and the pollen amount is negligible. Its S-genotype, determined using Polymerase Chain Reaction with a S-RNase gene-specific primer pair, is $S_3S_6$. The average optimum harvest time of 'Okjoo' is late June. The fruit is round in shape and its suture is shallow. Average fruit weight is 18.5 g, and it contains total soluble solids $7.66^{\circ}Brix$ and titratable acidity at 4.81%. Fruit skin color is green. Sometimes only the light side of the fruits seems to develop blush. The incidence levels of scab (Cladosporium carpophilum Thumen) and bacterial shot hole (Xanthomonas arboricola pv. Pruni) are quite low. Consequently, 'Okjoo' seems to be a promising new cultivar for Japanese apricot growers.

• Horticultural Science & Technology
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• v.31 no.6
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• pp.732-739
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• 2013

'Akihime' plums picked at mature stage (50-70% red coloration of the fruit skin) were stored at $1^{\circ}C$ under air or controlled atmosphere (CA) storage regime as following 3% $O_2$ + 1, 3, 5, and 7% $CO_2$ for 50 days for the purpose of assessing the effect of CA storage on the maintenance of fruit quality and the reduction of chilling injury. Fruits stored under CA storage regime showed reduced respiration as well as ethylene production rates compared to the fruits stored in air. Quality attributes including weight loss, Hunter 'a' values, soluble solids content, titratable acidity, and firmness showed smallest changes in fruits stored under CA conditions except for 3% $O_2$ + 7% $CO_2$. High incidence of physiological disorders including chilling injury, flesh browning, and decay were found in fruits stored under both air and CA of 3% $O_2$ + 7% $CO_2$. In our study, the CA storage regime of 3% $O_2$ + 5% $CO_2$ was found the most effective for maintaining overall fruit qualities of 'Akihime' plums produced in Korea, also delayed the development of chilling injury including lack of juiciness and flesh browning. From the results, storage at 3% $O_2$ + 5% $CO_2$ was selected as an optimal condition of 'Akihime' plum for extending storage life up to 50 days at $1^{\circ}C$.

• Korean Journal of Food Science and Technology
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• v.26 no.3
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• pp.300-304
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• 1994

To predict quality change of Kochujang distributed in the market, physicochemical properties were observed during storage at $13^{\circ}C$, $27^{\circ}C$ and $37^{\circ}C$ for 240 days. Moisture, crude protein and capsaicin contents were nearly constant for storage at the selected temperatures. Amino nitrogen, value of surface color and pH were decreased during storage while ammonia nitrogen and titratable acidity were increased. Storage temperature affected quality change significantly as higher temperature showed clear increase or decrease phenomena of above factors. Number of total cell count was not changed significantly, and fungi was not detected. From the correlation coefficient among physicochemical properties and sensory evaluation scores, the highest correlation was obtained in amino nitrogen content and sensory score. Degradation of amino nitrogen was a first order reaction, and the $Q_{10}$ value calculated from reaction constant was 2.98. Also, activation energy for the destruction of amino nitrogen calculated from Arrhenius equation was 15.34 Kcal/mole.

• Korean Journal of Food Science and Technology
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• v.35 no.6
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• pp.1174-1181
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• 2003

A part of Aspergillus oryzae koji was replaced with Bacillus sp. koji to improve the quality of kochujang, and the resulting effects on enzyme activities, microbial characteristics, and physicochemical properties were investigated during fermentation. The activity of amylase was higher in the kochujang prepared with Asp. oryzae koji. The activity of protease increased as the ratio of Bacillus. sp. koji increased. Viable cell counts of yeast and bacteria of the kochujang increased with increasing ratio of Bacillus sp. koji. The Hunter a-values of the Bacillus sp. koji kochujang were higher, and the degree of increase in the total color difference $({\Delta}\;E)$ was lower in the Bacillus sp. koji group. Consistency and water activity of the kochujang prepared with Bacillus sp. koji was higher, and the pH and titratable acidity of the kochujang also changed slightly. As the ratio of Asp. oryzae koji increased, sugar content decreased. However, the ethanol content of the kochujang did not significantly change. Amino nitrogen content of the kochujang increased, while ammonia nitrogen content decreased as the ratio of Bacillus sp. koji increased. After 12 weeks of fermentation, the result of sensory evaluation showed that C kochujang (75% of Asp. oryzae koji replaced by Bacillus sp.) was more acceptable (p<0.05) than the other groups in taste, color, flavor, and overall acceptability.

• Korean Journal of Food Science and Technology
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• v.35 no.6
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• pp.1193-1198
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• 2003

The effects of preferment levels prepared with lactic acid bacteria isolated from kimchi on the quality of white pan bread were studied. The aim was to investigate how preferment influenced the baking-technological, textural, and sensory properties of white pan bread. During the process of making white pan bread, the pH decreased as the preferment levels increased, whereas the titratable acidity increased. The loaf specific volume increased from 4.66 to $5.59\;cm^3/g$ as preferment content increased from $10%{\sim}25%$. The moisture content and water activity of the bread ranged from 40.77 to 41.49%, and 0.961 to 0.966, respectively, indicating that no appreciable differences were related with the preferment levels (p<0.05). The textural characteristics of white pan bread were highly correlated with the amount of preferment added. White pan bread containing preferment showed a decrease in hardness and gumminess, and an increase in springiness. The color of white pan bread was not significantly different from that of the control. In sensory evaluation, the values for volume, springiness, and umami were highest in the white pan bread with 20% preferment, and the sour and umami tastes increased with the amount of preferment.

• Korean Journal of Food Science and Technology
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• v.17 no.3
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• pp.213-218
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• 1985

As a way of improving the texture and flavor of soybean cheese, whey-say cheeses were made by coprecipitation of various mixtures of whey, whey powder, soy milk and soy protein powder, and mixed culture of str. lactis, str. cremoris and rennet were added, then the cheeses were cured at $15^{\circ}C$ for up to 10 weeks. Physicochemical characteristics of the cheese were investigated by analyzing pH, titratable acidity(TA), water soluble nitrogen, 10% TCA soluble nitrogen, amino acid composition, beany flavor, color and hardness. The pH of whey-soy cheeses during ripening changed from 5.3 to 4.2 after 5 or 6 weeks and maintained that value while that of soybean cheese maintained a higher pH value. TA of whey-soy milk cheeses was gradually increased to the value of 0.4-0.45 after 8 weeks, but that of soybean cheese reached only 0.2 after the same period. Water soluble and 10% TCA soluble-nitrogen increased steadily during ripening. Hardness of the whey-soy milk cheeses reached maximum after three weeks of ripening and greatest at those made from 3 : 1 mixture of whey and soy milk and that from soymilk. Color of the whey-soy milk chesses was lighter than that of soybean cheese. The bean flavor of soybean cheese was strong and persistent for the whole ripening period. Acid flavor was dominant in the whey-so milk cheese and masked the beany flavor partially.

• Food Science of Animal Resources
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• v.26 no.1
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• pp.127-135
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• 2006

This experiment was carried out to examine the fermentation properties of yogurt with bovine milk and soybean milk at the mixed ratio of 2:1 and added 0.1, 0.2, 0.4 and 1.0% red ginseng extract. The effect on promoting the fermentation by additives 0.1, 0.2, 0.4 and 1.0% red ginseng extracts were higher and pH was $3.90{\sim}3.94$ when Lactobacillus acidophilus KCTC3150 and Lactobacillus salivarius ssp. salivarius CNU27 were used. Titratable acidity showed a little inhibiting due to increasing red ginseng extract content. The average viable counts of lactic acid bacteria after 15 hour culture was the highest level of $6.26{\times}10^8cfu/mL$ when Lactobacillus acidophilus KCTC3150 was used, and the additives content of red ginseng extract was 1.0% The production of lactic acid was the highest and the concentration was 332.22 mM when Lactobacillus acidophilus KCTC3150 was used, and the additives content of red ginseng extracts was 1.0% Lactose hydrolysis was completely hydrolyzed when Lactobacillus acidophilus KCTC3150 and Lactobacillus salivarius ssp. salivarius CNU27 were used. The highest viscosity of yogurt was 780 cP when Lactobacillus acidophilus KCTC3150 and Lactobacillus salivarius subsp. salivarius CNU27 were used and red ginseng extract was added 1.0% The overall acceptability, $4.17{\pm}0.64$, was the highest when Lactobacillus salivarius subsp. salivarius CNU27 was used and the additives content of red ginseng extract was 0.2%.