• Korean Journal of Food Science and Technology
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• v.31 no.6
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• pp.1503-1510
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• 1999

This study was performed to investigate the physicochemical properties of Korean Citrus sudachi fruit which were harvested at different harvesting time(every 20 days from Sep. 3 to Nov. 8) and region(Seogwipo and Cheju city area). The average weight of Citrus sudachi fruit harvested from Seogwipo area was as twice as that of Cheju area at the same period. The moisture content in fruit peel increased by ripening of fruit, but that of fruit juice showed no difference. The content of reducing sugar in fruit peel and fruit juice increased 2 times from Sep. 3 to Nov. 8. The content of crude fiber decreased both in fruit peel and fruit juice as progression of ripening. Crude protein and ash contents decreased in fruit peel but revealed no differences in the fruit juice during the same period. pH decreased in fruit peel and juice with its ripening. The content of vitamin C decreased by ripening of fruit. The transmittance which is important quality factor in fruit juice increased from Sep. 20 to Oct. 13. The content of free sugar increased about 2 times in fruit peel from Sep. 3 to Nov. 8 and showed 4 times increase in fruit juice at the same period. In the composition ratio of mineral, Ca and K were abundant in the fruit peel, but only K was the most abundant mineral in fruit juice than any others.

• Journal of the Korean Society of Food Science and Nutrition
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• v.20 no.3
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• pp.233-240
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• 1991

Effects of various sub-ingredients (hot pepper, garlic, ginger, green onion, leek, salted and fermented anchovy juice, and sugar) on the sensory quality of Korean cabbage kimchi were investigated. Sixteen sensory attributes were selected and their intensities evaluated by 20 panelists. The kimchi had an unbarmonized taste and unpleasant flavor when fermented with individual sub-ingredients, but had a well harmonized taste when fermented with all sub-ingredients. Hot pepper, ginger and garlic contributed to reduction of the unpleasatnt taste and moldy odor. The strong garlic flavor was reduced by adding green onion and leek. Salted and fermented anchovy juice gave a palatable taste, and the overall taste was improved by adding sugar. All sub-ingredients except sugar reduced the sour tasts.

• Journal of the Korean Society of Food Culture
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• v.21 no.6
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• pp.644-652
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• 2006

This study was investigated the utilization of pomegranate(P) as coagulants for 새려 manufacture, the quality characteristics and shelf-life on tofu made by P1(fruit juice of pomegranate 1%) and P2(fruit juice of pomegranate 2%) and P3(fruit juice of pomegranate 3%) and P4(fruit juice of pomegranate 4%) and P5(fruit juice of pomegranate 5%) were investigated and compared to G.D.L(C). And also, total microbe and tatal acid of the tofu were determined during storage at $0^{\circ}C^$. The results are summarized as follow P3(493.3g/500ml) compared to C(485g/500ml) showed the highest yield. Turbidity of tofu was increased as the proportion of pomegranate was increased, while pH of tofu was increased as the proportion of pomegranate was decreased. $L^{\ast}^{\ast}^{\ast}$ value of C tofu was highest, $a^{\ast}^{\ast}^{\ast}$ value of tofu was increased as the proportion of pomegranate was increased and $b^{\ast}^{\ast}^{\ast}$ value of C tofu was higher than those of other tofus. The hardness of tofu coagulated with pomegranate showed higher than that of coagulated G.D.L. The cohesiveness of P4, P5 showed higher than C tofu, but those of other tofus showed lower than C tofu. The springiness of tofu showed in the order of P4>P5>P3>P2>P1, gumminess of P5 tofu was highest. The Brittleness of tofu was increased as the proportion of pomegranate increased. The pH value of tofu coagulated with pomegranate increased during storage at $0^{\circ}C^$. During the storage period of tofu, pH and total acid showed a maximum change in C tofu. Generally the total plate counts of bacteria of all tofu increased during storage at $0^{\circ}C^$, and those of tofu with added pomegranate were shown to be lower than C tofu. The results of S.E.M(scanning electron microscopes), the lower hardness showed the more soft and the smaller particle, The particle of C tofu was small and uniformity but the size of P4, P5 tofu showed coarse. In the sensory evaluation of all tofu, sleekness, nutty, chewiness and smoothness, appearance and overall quality was the highest in C tofu. In the sensory evaluation of tofus coagulated with pomegranate. overall quality was the highest in P2.

• Journal of the Korean Society of Food Science and Nutrition
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• v.35 no.3
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• pp.378-382
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• 2006

Clarified orange juice was prepared using different clarification methods including centrifugation, enzyme treatment, ultrafiltration (UF), and combined treatment(CT). Effect of clarification methods as well as other quality parameters were investigated. Clarification was improved with increase in centrifugation speed and by lowering operating temperature. The optimum condition for centrifugation process was $5^{\circ}C$ and 10,000 rpm. UF and CT processes were very effective to produce clarified orange juice. The optimum condition of UF process was $45^{\circ}C$ and 150 kPa considering flux and turbidity CT did not significantly improve the clarification efficiency since most of the clarification was already achieved during UF process. $L^*$-values increased while $a^*$-values decreased significantly after clarification regardless of methods (p<0.05) Considering color, and recovering rate of vitamin C and soluble solids, UF process was superior than the other methods in producing clarified orange juice.

• Korean Journal of Food Science and Technology
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• v.20 no.3
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• pp.419-425
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• 1988

The clarified apple juice was pre-concentrated by reverse osmosis system as a trial for reduction of heat treating time and quality drop in concentration of the juice. The permeate fluxes through CA 865 and CA 960 membranes were higher than those of HR 95 and HR 98 membranes even at the low operating pressure. In the concentration limit depended on the membranes used, HR membranes operated at 60 bar showed $29.0^{\circ}$Brix, and the time required to reach the limit was 86 min for HR 95 and 71 min for HR 98. In cases of CA membranes run at 30 bar, the juice concentration was linearly increased without the limit, and longer time to reach the same concentration was required in comparison with HR membranes. As the juice concentration was increased, the loss of soluble solids was increased, and the average contents of soluble solids in the permeate passed through HR 95, HR 98, CA 865 and CA 960 were 1.3, 0.5, 7.5 and $2.3^{\circ}$ Brix, respectively, in the juice concentration range of 20.0 -$25.0^{\circ}$ Brix. The lower amounts of sugars, total acid and flavor volatiles were involved in the permeate through HR membranes, especially HR 98 than in the permeate through CA membranes.

• Food Science and Preservation
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• v.21 no.2
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• pp.199-205
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• 2014

This study was conducted to investigate the physicochemical properties and antioxidant activity of black Doragi-apple juice to increase the utilization of Doragi, which is known as a high-functional horticultural crop. To prepare the black Doragi, it was steamed for 15 days at $60^{\circ}C$ and was then dried at $30^{\circ}C$ for 3 h. The five types of black Doragi-apple juice were prepared based on different mixing ratios of black Doraji extract, apple extract, and jujube extract. The mixing ratios of black Doraji extract, apple extract, and jujube extract were 3:3:1, 4:2:1, 2:4:1, 2:2:1, and 2:6:1 for samples A, B, C, D, and E, respectively. The pH and acidity of black Doragi-apple juice were within the ranges of 3.9-4.15 and 1.26-1.51%, respectively. Black Doraji-apple juice E showed the highest sugar content (9.33 $^{\circ}Brix$), reducing sugar content (85.05 mg/mL), and sugar content/acid ratio (6.98). Based on the sensory evaluation, sample C was most preferable in terms of color, taste, sugar-acid ratio, and overall preference, except for the flavor. Black Doragi-apple juice D showed a higher total polyphenol content (706 ${\mu}g/mL$) than sample C (586.22 ${\mu}g/mL$), but there was no statistically significant difference between samples C and D in terms of antioxidant activities. Therefore, it is suggested that the best mixing ratio of black Doraji extract, apple extract, and jujube extract for the production of the best black Doragi-apple juice with excellent taste and antioxidant activities is 2:4:1 (sample C).

• Food Science and Preservation
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• v.14 no.3
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• pp.256-262
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• 2007

Grape juice, one of the most valuable fruit derived product has large amounts of phenolic compounds which provide many of the health benefits. Campbell grape juice, divided into Sample A(without seeds and stems), Sample B(with seeds only), Sample C(with seeds and stems) were processed and assessed for its components, sensorial attributes and functional properties as influenced by the addition of seeds and stems. The presence of seeds and stems in the processing of Campbell grape juice has significant effects on pH and total soluble solids($^{\circ}Brix$) but showed no significant effects on other physicochemical and color properties and corresponds to an increase in total phenolics, radical scavenging activity, total anthocyanin and total flavonoid The sensory evaluation showed that there is no significant differences among the samples but were all liked moderately to very much by the panelists. The result of this study demonstrated that seeds and stems can be included in the processing of Campbell grape juice as it enhances the juice functional properties without altering its physicochemical and sensorial properties.

• Korean Journal of Food Science and Technology
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• v.35 no.4
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• pp.628-634
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• 2003

To investigate the effects of storage and pasteurization temperature on the quality of kiwi juice $(13.5^{\circ}Brix)$, the Kiwi juice was pasteurized at 65, 75 and $85^{\circ}C$ for 15 sec. The microbial, physicochemical measurements and sensory evaluations were conducted at the same condition during storage at 4 and $25^{\circ}C$ for 30 days. Most of the vegetative bacteria cells in kiwi juice were destroyed by heat treatment over $65^{\circ}C$, and they did not actively grow in kiwi juice after pasteurization. The D values of bacteria in kiwi juice by tubular type of heating exchange were 4.17, 1.47 and 0.81 sec at 65, 75 and $85^{\circ}C$, respectively. The growth of microorganisms during storage were not detected in the most samples. The amounts of vitamin C decreased as the pasteurization-storage-temperature and storage time increased. While reducing sugar increased as the pasteurization-storage temperature-storage time increased, it decreased rapidly after 20 days of storage. Hunter's color values L, a and b of stored kiwi juice were decreased at all storage conditions, browning reaction rate increased as the pasteurization-storage-temperature was decreased.

• Korean Journal of Food Science and Technology
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• v.54 no.4
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• pp.445-454
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• 2022

This study aimed to improve the physiological activity of onion juice via lactic acid bacterial fermentation. Seven types of lactic acid bacteria were used for the fermentation of onion juice. The pH and sugar content of the onion juice decreased, while its titratable acidity increased after lactic acid bacteria fermentation, and the cell count of lactic acid bacteria was 7.31-10.40 log CFU/mL. The total free sugar content decreased, while the total organic acid content increased in the fermented onion juice. Quercetin content of the fermented juice was 0.13-0.53 mg/kg. The total polyphenol and flavonoid contents increased after fermentation. Additionally, the 2,2-diphenyl-1-picryl-hydrazyl-hydrate free radical and 2,2'-azinobis-(3-ethylbenzothiazoline-6-sulfonate) radical cation scavenging activities were increased by fermentation. Overall, lactic acid bacteria fermentation of onion juice enhanced its physiological activity. Based on these findings, Bifidobacterium breve KCTC 3441 was selected as the onion juice fermentation strain.

• Journal of the Korean Society of Food Science and Nutrition
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• v.27 no.6
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• pp.1059-1064
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• 1998

Fermented beverage using lactic acid bacteria isolated from kimchi was investigated. Lactic acid bacteria KL 1, KD 6, KL 4 strains from kimchi, or obtained Lactobacillus acidophilus, Lactobacillus plantarum, Leuconostoc mesenteroides with and without yeast(Saccharomyces cerevisiae) were inoculated in fruit vegetable juice for single and mixed culture fermentation. During the fermentation by bacterial strain and yeast for 1~3 days at 30oC, various fermentation behaviors were observed. The growth rate of mixed culture of KL 1 and yeast was higher than that of single culture by KL 1 alone during the fermentation. The amount of organic acid produced by the mixed culture fermentation of KL 1 and yeast was 0.82%(3 day) or 0.58%(1 day) and with the final pH of 3.3(3 day) or 4.2(1 day). These mixed culture systems of isolated strains or other bacterial strains had almost similar results of growth rate and acid production. Among several bacterial strains, KL 1 was suitable for the mixed culture fermentation with yeast in terms of desirable fermentation behavior and organoleptical quality. The selected strain, KL 1 was identified as Leuconostoc spp. through the series of tests on carbohydrate fermentation and biochemical characteristics.