• Journal of the Korean Society of Food Science and Nutrition
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• v.36 no.10
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• pp.1341-1350
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• 2007

This study was designed to ultimately develop a highly efficient mass production technology of bacterial cellulose isolated from the citrus gel fermented by G. hansenii TL-2C. Pilot equipment made with FRP vessel length (665 mm) ${\times}$ width (375 mm) ${\times}$ height (210 mm) was developed for mass production of the citrus gel. To develop the optimal conditions for mass production of citrus gel, comprised of citrus juice (6,000 mL) diluted 100 times, containing 5% seed bacteria, 10% sucrose, and 1% ethanol, citrus juice was fermented at $30^{\circ}C$ for 14 days, and gel productivity in pilot system was examined. BC was isolated and purified from the citrus gel, and their chemical composition and physicochemical properties were investigated.

• Korean Journal of Food Science and Technology
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• v.31 no.6
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• pp.1613-1618
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• 1999

Extracts of Citrus sudachi juice and peel were obtained by several organic solvents such as hexane, acetone, ethyl acetate and methanol. Their antimicrobial spectrum were determined against 14 strains of gram positive and 4 strains of gram negative bacteria by paper disk method and minimal inhibitory concentration (MIC) was also obtained. Antimicrobial activities of solvent extracts from Citrus sudachi juice showed stronger than those of solvent extracts from peel. Acetone extract from juice showed the strongest antimicrobial activity among extracts, but the hexane extract did not show antimicrobial activities on tested target strains. The MIC was differant among tested strains; i.e. 0.5% (v/v) to Bacillus subtilis, 1% to Pseudomonas fragi, 1.5% to Listeria monocytogenes and Escherichia coli O157:H7, 2% to Propionibacterium acnes and Salmonella typhimurium, and 2.5% to Staphylococcus aureus.

• The Korean Journal of Food And Nutrition
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• v.23 no.3
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• pp.332-341
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• 2010

The chemical composition characteristics of jujube wine using different preparation methods including extraction in -soju (25%) and fermentation were investigated. The jujube wine was prepared by soaking in soju using- whole fruit(WJ-S1) or seed-removed fruit(WJ-S2). Fermentations of the jujube wine were started by using whole fruit(WJ-F1), seed-removed fruit(WJ-F2) or extracts of whole fruit(WJ-F3) after adding 24% sucrose. The pH of all samples decreased from a range of 4.92~5.42 at the start time to 3.66~4.97 after 100 days. The treatment WJ-F3 showed the lowest pH among all treatments. Total acid content was 0.67~1.01% at the initial stage and then changed to 0.51~0.88% after 100 days. Total sugar and reducing sugar contents were 1.20~13.8% and 0.50~4.45% at initial stage and then changed to 1.53~4.52% and 1.75~3.82% after 100 days respectively. These sugars decreased during the preparation and fermentation of the jujube wine. The amounts of free sugars including fructose, glucose, and sucrose ranged from 1.53~4.52% and treatment WJ-F3 showed the highest amount(1.95~13.64%) compared the other treatment. Glucose level were high in treatment WJ-S1 and WJ-S2, and fructose was increased in treatments WJ-F1, WJ-F2, and WJ-F3 after 60 days. Amino nitrogen content was 0.02~0.11% after 20 days and 0.07~0.14% after 40 days respectively. Solid content was 2.68~7.76% at the initial fermentation stage and changed to 4.81~9.73% after 100 days. Hunter color(L values) were 88.45~96.74 at the initial stage and then changed to 92.62~100.45 after 100 days. Preference tests a significant difference between the two types (extraction and fermentation) of jujube wine. And treatment WJ-S2 received the highest preference scores among the all treatments.

• Journal of the Korean Society of Food Science and Nutrition
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• v.11 no.3
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• pp.67-74
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• 1982

The effect of various pH levels, temperatures. organic acids, inorganic salts, metal ions on the stability of the anthocyanins pigment (pH 3.7) from the juice of raspberries were investigated. Initial absorption of total anthocyanin was decreased as pH increased from 1.0 to 7.0. Total amount of anthocyanin reached the highest at pH 3.7 and least at pH 7.0. The total anthocyanin content decreased rapidly with the increasing temperature. Many organic acids were found to enrich and stabilize the color density at 520nm in anthocyanin solution (pH 3.7). The hyperchromic effect of saturated n-carboxylic acid increased in the following order; formic acid> acetic acid>n-butyric acid>propionic acid. On the polycarboxylic acid, especially, malic acid showed 550$\sim$930% higher than control group. On the inorganic salts (0.5M), sodium perchlorate had the most hyperchromic effect and followed by sodium sulfate>sodium chloride>sodium phosphate, monobasic. Among the metal ions, both aluminium ion and cupric ion much more accelerated the anthocyanins degradation as compared with other metal ions.

• Food Science and Preservation
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• v.17 no.4
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• pp.563-570
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• 2010

We sought to ferment wine from mulberry (Morus alba) juice. The soluble solid content was $9.5{\sim}14.5^{\circ}brix$ on day 6 of fermentation, and gradually fell later; sugar was not further consumed when $3^{\circ}brix$ was attained. Alcohol content rose dramatically on day 6 of fermentation, being 4.5% (v/v) at fermentation temperatures of 16C and 18C, 6.5% (v/v) at 20C, and 8.0% (v/v) at 25C, rising further to 10.5~11.5% (v/v) on day 48, at higher culture temperatures. Citric acid, malic acid, and oxalic acid were present in mulberries. The levels of both citric and oxalic acid fell after fermentation, whereas malic acid concentration increased. All of fructose, glucose, maltose, and sucrose were fermented. Electron-donating ability (EDA) was elevated to over 90% of the control value in mulberry juice diluted to 40% (v/v). SOD-like activities in juice and wine were 80.1% and 72.1% of the control value. Nitrite-scavenging abilities (NSAs) were 86.2% and 85.2% of control in undiluted juice and wine, respectively. Mulberry juice had an activation level higher than that of mulberry wine, but functionality neither rose nor fell after fermentation. Insensory evaluation, the overall wine score was better than average, at 5.00, demonstrating the commercial potential of mulberry wine.

• The Korean Journal of Food And Nutrition
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• v.10 no.2
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• pp.145-150
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• 1997

This study was performed to compare the changes of quality in citron(Citrus junos Sieb) juice between sampleII stored at 5$^{\circ}C$ for 1 year after extraction and sampleI made from raw citrons by the belt-pressing extraction method. Compared with sampleI, the soluble solid of sampleII was decreased more than 1$^{\circ}$brix, and the moisture increased 3%. The acidity reduced from 5.83 to 5.23 at the pH rose from 2.68 to 2.84. Although it decreased more than 50% in vitamin C and over 20~30% in amino acid, the changes of the other proximate components, amino nitrogen and free sugar content were very little at the range 0.1~1.0%. Volatile compounds in citron juices between sampleI and II were analyzed by GC and GC-MS. Sample I and II showed about 70 of volatile compounds. But only 13 compounds were identified by mass spectrometer. Major volatile compounds were aromatic compounds of limonene, terpinene, terpineol and terpinolene. Amounts of volatile compounds in citron juices depended on the storage period. The recovery of volatile compounds of citron juices, reduced 30~50% after storage for 1 year and the trace component disappeared during storage. The sensory characteristics including color, aroma, taste and overall acceptability and sugar recipe were not significantly.

• Food Science and Preservation
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• v.9 no.2
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• pp.154-160
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• 2002

This study was carried out to investigate the efficacy of electrolyzed oxidizing(EO) water, electrolyzed oxidizing water with 0.5% citron juice and 0.1% aluminium potassium sulfate (APS) solution as the storing liquids to maintain quality and extend shelf life of peeled taro. Water content of peeled taro increased from 80.55% to 82.12∼84.24% after 25 days storage due to moisture absorption. However, there were no significant difference between treatments. In case of color value of peeled taro, L value was slowly decreased and a, b value was generally increased. Texture of peeled taro decreased from initial 4,520$\pm$75 g to 4,160$\pm$80 g after 25 days storage in EO water with 0.5% citron juice, which is the least reduction value in all treatments. Treatment of EO water with 0.5％ citron juice maintained 6.99 mg%(57%) of total vitamin C after 25 days storage which showed highest total vitamin C content between treatments. In most treatments, total sugar was decreased in fast rate for 15 days storage and slowly decreased after 15 days storage. Free sugar content was not changed significantly during storage. In case of sucrose content which is the major portion of free sugar, reduction continued until the midst of storage. and after that it increased to 1.5∼2 times of initial contents. However, there were no differences between treatments and storage days in contents of fructose, glucose and maltose. Major amino acids in peeled taro were aspartic acid and glutamic acid with 1,084.8 and 691.8 mg/100g respectively. At 25 days of storage, aspartic acid content in treatment of EO water was increased about 13.9%. Treatment of EO water with 0.5% citron juice was the most effective in respect to the reduction ratio of total amount of essential amino acids.

• Food Science and Preservation
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• v.14 no.6
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• pp.702-708
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• 2007

The effects of pectinase treatment and other processing conditions on juice yield from Rubus coreanus, and physicochemical changes during alcohol fermentation, were investigated. The yield from R. coreanus increased by 8.60% with Pectinex 100L treatment (500 ppm, 30 min) compared to a control group. The soluble solid content in the group fermented at $24^{\circ}Brix$ by addition of sucrose (24B-group), and the group fermented at $8^{\circ}Brix$ by addition of 16% sucrose after 4 days of fermentation (8B-group) decreased to $8.2{\sim}8.3$ and $7.7{\sim}8.0%$ after 10 days of fermentation, respectively, and no significant differences were observed with Pectinex 100L treatment. Initial titratable acidity in the enzyme treatment was slightly higher ($1.18{\sim}1.22%$) than for the control group (1.02%). The initial $L^*$ and $b^*$ values of R. coreanus juice decreased with enzyme treatment, and the $a^*$ value increased, but the color difference (${\Delta}E$) between the control and enzyme treatment gradually decreased with fermentation time. The ethanol contents in the 24B-group and the 8B-group were $16.01{\sim}16.22%$ and $13.29{\sim}13.52%$, respectively, after 10 days of fermentation. The methanol contents in the enzyme treatment and the control were $0.359{\sim}0.404$ and $0.520{\sim}0.604$ mg/mL, respectively, and within standard regulations (1 mg/mL).

• Journal of the East Asian Society of Dietary Life
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• v.22 no.2
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• pp.264-270
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• 2012

The effect of pectinase on wine production and quality during wine fermentation was investigated in an experiment a laboratory scale (2 kg grape/5 L tank). Experimental results show that the enzyme-treated sample displayed a 13% higher rate of grape juice production compared to control (enzyme-untreated). In the case of color analysis, the addition of pectinase improved the color quality of wine in terms of both color intensity and hue values. The results show that pectinase enhanced both dark-red color and clarity of wine during the fermentation period. Further, the methanol concentration of the wine sample treated with pectinase reached 225.32 mg/L (control: 100.72 mg/L) due to hydrolysis of pectin. Sensory analysis after fermentation showed that pectinase significantly increased the color, smell, taste, and touch intensity scores of wines compared to control.

• Food Science and Preservation
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• v.15 no.1
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• pp.21-29
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• 2008

This study investigated the fermentation and quality characteristics of a fermented beverage, prepared by semi-anaerobic culture, using sea tangle extract. A central composit design using alcohol(0, 0.5, 1.0, 1.5, 2.0% [all v/v] ), sugar(0, 5, 10, 15, 20% [all w/v] ) and $65^{\circ}Brix$ citrus juice(0, 1.0, 2.0, 3.0, 4.0 % [all v/v] ) was used to find the optimal mix for fermentation. Sensory characteristics, such as color, flavor, taste, sweetness, saltiness, sourness and overall quality, were measured using a response surface methodology computer program. The optimal conditions that produced the highest acidity of 0.94 were 2.0 % ethanol, 10.17 % sucrose and 1.99 % citrus juice. The optimal conditions that produced gel 20.13 nun in thickness were 1.98% alcohol, 10.94% sucrose and 1.62% citrus juice. The overall optimal conditions that satisfied all the sensory requirements for a sea tangle beverage were 1.0% alcohol, 10.0% sucrose and 4.05% citrus juice.