• Korean Journal of Food Science and Technology
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• v.31 no.2
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• pp.448-457
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• 1999

Citrus fruits are consumed worldwide due to their unique flavor and nutrition value. It is necessary to remove the haze material as well as to minimize the loss of major compounds such as organic acids, sugars, and ascorbic acid in membrane processes for clarification of juice. The objective of our research was to select the best membrane among one surface filter (Whatman No.4) and five microfiltration filters (GF/A, GF/D, GF/F, Gelman, and SM). Tangerine fresh blended with three times of water was partially clarified with 170 mesh followed by prefiltration in a Samduck filtration system. The best membrane was selected by measuring the amounts of major compounds in the permeates as well as the flux which were statistically analyzed with SAS program. The foulants on the membrane surface were observed by SEM. The flux of GF/A and GF/F decreased with time at probability 0.10. Gelman, SM, and GF/D maintained the stable flux. Gelman showed the highest total scores including nutritive value (the amounts of citrate, malate, and ascorbic acid) and purchasing need (brix and color). Therefore, the microfiltration membrane process was a very effective method in tangerine juice clarification and Gelman type A/E was proved to be the best membrane among the five microfiltration membranes.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.44 no.2
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• pp.141-148
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• 2011

This feeding experiment was conducted to investigate the effects of dietary inclusion of various additives on growth performance, hematological parameters, fatty acid composition, gene expression and histopathological changes in juvenile olive flounder (Paralichthys olivaceus). Eleven isonitrogenous (49% crude protein) and isolipidic (10% crude lipid) experimental diets were formulated: no additives (Con); 5% kelp meal (Ke); 10% krill meal (Kr); 1% garlic powder (Ga); 1% citrus meal (Ci); 3% onion powder (On); 1% ginger powder (Gi); 1% mugwort powder (Mu); 1% licorice powder (Li); 1% wasabi powder (Wa); and a mixture (Mix) of these additives. Three replicate groups of juvenile flounder (average weight of 8.5 g) were fed one of the experimental diets to visual satiety twice a day for 15 weeks. The dietary inclusion of additives did not affect survival, weight gain, specific growth rate feed efficiency, daily feed intake, daily protein intake, protein efficiency ratio, hepatosomatic index and visceralsomatic index of the fish. Plasma triglyceride levels were significantly lower in fish fed the Ke, Ga, On, Gi, Mu, Li, and Mix diets than in fish fed the control diet. Plasma glucose, glutamic oxaloacetic transaminase and total cholesterol did not differ among dietary treatments. No significant difference was observed in fatty acid composition and lipid content of the dorsal muscle in fish fed the experimental diets. Myosin gene expression did not differ significantly among treatments after 5 weeks but was significantly lower in fish fed the Kr, Ci, Li, and Mix diets than in control group after 15 weeks. Histopathological analysis showed mild gill hyperplasia and mild necrosis of liver parenchymal cells in several individuals of each experimental group. These conditions were also observed in the control group and were not thought to be related to the inclusion of feed additives. The present findings indicate that the dietary inclusion of additives did not affect growth performance, fatty acid composition, gene expression, and histopathological changes in juvenile flounder. However, plasma triglyceride content may be reduced by supplementation with 5% kelp meal, 3% onion powder, 1% garlic powder, 1% ginger powder, 1% mugwort powder, and the additive mixture.

• Food Science and Preservation
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• v.13 no.5
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• pp.649-654
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• 2006

To enhance beneficial effects of citron fruits, anticancer and antioxidant activities of citron fruits extracts were assessed with or without ascorbic acid. Total phenolic acids and flavonoids of fruits peels and flesh extracts were determined. Fruits peels contained more phenolic acids and flavonoids than those detected in flesh extracts. Scavenging activities of 1,1-diphenyl-2-picrylhydrazyl radicals and reducing powers were increased depending on the concentration. The antioxidant activities on oxidation of linoleic acid emulsion incubated at $50^{\circ}C$ were increased but the effect was small to that of butylated hydroxy toluene and ascorbic acid. The anti-tumorigenic effect of these compounds were investigated. They were shown to inhibit the in vitro proliferation of four human tumorigenic cell lines, HT-29, MCF-7, DU-145 and HepG2, in a doso-dependent manner. This study demonstrated that the antioxidant and anticancer activities of citron fruits extracts were derived from their phenols and flavonoids.

• Journal of Microbiology and Biotechnology
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• v.26 no.6
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• pp.989-998
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• 2016

Acidic endo-polygalacturonases are the major part of pectinase preparations and extensively applied in the clarification of fruits juice, vegetables extracts, and wines. However, most of the reported fungal endo-polygalacturonases are active and stable under narrow pH range and low temperatures. In this study, an acidic endo-polygalacturonase (EPG4) was purified and characterized from a mutant strain of Penicillium oxalicum. The N-terminal amino acid sequence of EPG4 (ATTCTFSGSNGAASASKSQT) was different from those of reported endo-polygalacturonases. EPG4 displayed optimal pH and temperature at 5.0 and 60-70℃ towards polygalacturonic acid (PGA), respectively, and was notably stable at pH 2.2-7.0. When tested against pectins, EPG4 showed enzyme activity over a broad acidic pH range (>15.0% activity at pH 2.2-6.0 towards citrus pectin; and >26.6% activity at pH 2.2-7.0 towards apple pectin). The K_m and V_max values were determined as 1.27 mg/ml and 5,504.6 U/mg, respectively. The enzyme hydrolyzed PGA in endo-manner, releasing oligo-galacturonates from PGA, as determined by TLC. Addition of EPG4 (3.6 U/ml) significantly reduced the viscosity (by 42.4%) and increased the light transmittance (by 29.5%) of the papaya pulp, and increased the recovery (by 24.4%) of the papaya extraction. All of these properties make the enzyme a potential application in the beverage industry.

• Journal of Life Science
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• v.26 no.5
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• pp.563-570
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• 2016

Onion vinegar has an undesirable flavor and taste that results from alcohol and acetic acid production from fermentation. In this study, we have used onion vinegar to develop an onion vinegar beverage with better sensory quality. The objective of this study was to determine the optimum blending ratio by using response surface methods to produce an onion vinegar beverage containing Yuza (Citrus junos Sieb ex Tanaka). The optimal formula for a fermented onion beverage was determined using a central composite design by the response surface methodology. The independent variables were obtained by regression analysis of the reaction surface of brown sugar, apple extracts and Yuza extracts. The optimum mixing ratio for onion vinegar:water:brown sugar:apple extracts:Yuza extracts was 6.0:77.6:4.9:9.2:2.3 (w/w). The actual overall acceptance was 7.08 under optimum conditions, which was close to the maximum predicted value of 6.96. The concentration of phenolic compounds, total flavonoids, and quercetin present in the onion vinegar beverage was 14.8 mg/100 g, 2.6 mg/100 g and 1.4 mg/100 g, respectively. The onion vinegar beverage showed antimicrobial activity against Staphylococcus aureus, Escherichia coli, Salmonella typhimurium and Enterobacter aerogenes. It also showed antioxidant effects, with a DPPH radical inhibition rate of 18.2% and superoxide dismutase (SOD)-like activity of 11.5%. In conclusion, the onion vinegar beverage described here seems to have nutritional value and potential biological activity.

• The Korean Journal of Food And Nutrition
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• v.27 no.6
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• pp.1051-1058
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• 2014

Yuza (Citrus junos) had 3 varieties and they had variable physiochemical properties. This study analyzed free sugar, hesperidine, naringin, flavonoid contents and antihypertensive activities according to variety and harvest time of Yuza. Three Yuza varieties, native (C. junos I), improved I (C. junos I + Poncirus trifoliata), improved II (C. junos I + C. junos II) were used. Harvest time could influence biochemical properties of Yuza such as acidity and $^{\circ}brix$. When the Yuza harvested at behind of season, the sugar/acid ratio went up because the acidity was decreased but sugar content was increased. Fructose content was dramatically high at November, Yuza of the season. Total flavonoids was high in pulp parts of improved II and in juice of native one harvested at October. The content of hesperidin and naringin in peels and juices were high in immature fruits fresh-picked at July since then they were decreased steadily and there were no difference according to varieties. The angiotensin converting enzyme (ACE) inhibition was powerful at pulp of Yuza in particular native one picked at November.

• Korean Journal of Food Science and Technology
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• v.9 no.4
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• pp.251-254
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• 1977

Pectin, hesperidin and naringin were extracted from hot air-dried peel ($60^{\circ}C$, 1 hr and air velocity 160 fpm) of citrus produced in Korea in order to see the amount of each component contained in the peel. Pectin was extracted by three different methods and the quality and contents of the pectins were determined respectively. 1. The pectin yield by the total pectic substance method was the highest (26.0% for unshiu (U) and 28.5% for natsudaidai (N) expectedly and the soluble pectic substance method the least (13.5%(U) and 15.6% (N)) The yield by method III (extraction by water at pH 1.5 followed by isopropanol precipitation) was intermediate (18.1% (U) and 20.8%(N)). Anhydrouronic acid (AUA) content was the highest (92.0% (U) and 90.3%(N)) in those by method III. The AUA contents of the other pectins were 80.0% for soluble pectin (for both U and N), 71.6% for the commercial pectin (Sunkist Groups Inc., U.S.A.), 58.0%(N) and 63.4%(U) for total pectic substance. 2. The methoxyl content of total pectic substance was the lowest (4.81%(U) and 4.88%(N)). However, there was no significant difference in methoxyl content among the rest which were found to have low levels(5.27-7.20%). 3. The pectin by method III gave the highest jelly strength. The commercial pectin, soluble pectice substance and total pectic substance were next in order. 4. The hesperidin content of unshiu was 5.07% (dry basis) and the naringin content of natsudaidai 3.03% (dry basis).

• Applied Biological Chemistry
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• v.40 no.3
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• pp.209-214
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• 1997

The canned fruit flesh of orange (Onju, Citrus unshi Marc.) was stored at $5^{\circ}C,\;15^{\circ}C,\;and{\;}30^{\circ}C$ for 4 months and the contents of sugar, organic acids and vitamin C of stored orange were investigated. The contents of reducing sugar of orange stored for 4 months slightly increased from 4.91% to $5.39{\sim}7.95%$ and decreased as the temperature rised. The sugar was composed of $6.63{\sim}18.09%$ sucrose, $3.86{\sim}9.12%$ glucose and $3.59{\sim}9.51%$ fructose. The content of sucrose used in manufacturing process was the highest and decreased as the temperature rised and as the storage period prolonged, whereas the contents of glucose and fructose increased as the storage period prolonged. The content of citric acid in the sample was the highest $(50.41{\sim}90.15\;mg%)$ among the-citric, malic, maleic, ${\alpha}-ketoglutaric$ and oxalic acids. The organic acids decreased as the temperature rised after storage for 4 months. The content of vitamin C was $8.28{\sim}14.29\;mg%$ and decreased most pronouncedly at $30^{\circ}C$ after storage. The color of the samples did not change significantly, but the degree of transparency, L was $20.41{\sim}23.01$ after storing the sample.

• Korean Journal of Food Science and Technology
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• v.38 no.2
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• pp.197-201
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• 2006

Long-term storage technology was developed to extend shelf-life of citron (Citrus junos). Changes in quality characteristics of blanched and frozen citron peels (type A, without blanching for control; type B, blanched at $95^{\circ}C$ for 2 min; type C, blanched at $95^{\circ}C$ for 2 min, sugar added; type D, blanched at $95^{\circ}C$ for 5 min) during frozen storage were evaluated. Citron jam was prepared using frozen citron sample B, which showed the highest quality characteristics during storage, and high quality characteristics, such as yield and overall acceptability, were obtained when using 40% frozen citron, 41% sugar, 18.56% glutinous starch syrup, 0.39% pectin, and 0.05% citric acid. During storage of both blanched and frozen citron peels and citron jam made of frozen citron peel, changes in characteristics such as pH, total acids, soluble solids, and browning, were lower than those of control. Sensory evaluation for sourness, sweetness, and overall acceptability of citron jam made with frozen citron peel during storage showed higher values than those of control.

• Korean journal of food and cookery science
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• v.13 no.3
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• pp.286-292
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• 1997

The purpose of this study was to investigate the effect of citron (Citrus junos) on Dongchimi (watery radish kimchi) fermentation. Dongchimi with various levels (0, 1, 2, 4, 6％) of citron was fermented at 10$^{\circ}C$ for 36 days. The pH of Dongchimi decreased slowly in all samples during fermentation, however, it was slightly lower in citron-added Dongchimi. Total acidity and turbidity of Dongchimi increased gradually during formentation, in which the level of increase was greater as the ％ of added citron increased. However, the total acidity and turbidity of Dongchimt without citron increased dramatically on 36$\^{th}$/ day of fermentation, and reached the values similar to those of Dongchimi with 6% citron. Reducing sugar content increased gradually up to 15∼23 days of fermentation and decreased rapidly for the rest of the period. The content of vitamin C was much higher in citron-added Dongchimi, and especially it was 4 times higher than that of without citron at the beginning of fermentation. The number of lactic acid bacteria reached the maximum on 15$\^{th}$/ day in citron-added Dongchimi and on 30$\^{th}$/ day in Dongchimi without citron, and decreased thereafter.