• Textile Coloration and Finishing
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• v.17 no.3 s.82
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• pp.16-25
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• 2005

In this research, we investigated hydrolysis of the ester crosslinking on cotton fabric treated with polymer of maleic acid(PMA), citric acid(CA) and combination of polymer of maleic acid and citric acid using Fourier transform infrared spectroscophy. The rate of hydrolysis of the ester crosslinkage increased with pH regardless of the type of polycarboxylic acid used and even after hydrolysis for 256 hour in pH 13_4 solution, the treated fabric retained $10-20\%$ ester crosslinkage. The durability to alkaline hydrolysis of the ester crosslinkage formed by CA was lower than that of by PMA and combination of poly(maleic acid) and citric acid indicating that the ester formed by CA on the cotton fabric is more susceptible to hydrolysis than that formed by PMA and combination of PMA and CA. The total amount of ester and polycarboxylic acid molecules removed from fabric increased with increasing hydrolysis time but the rate of hydrolysis of ester linkage were higher than that of removal of polycarboxylic acid molecule from the fabric. The characteristic of hydrolysis of fabric treated with combination of PMA and CA was related with the mixing ratio of PMA and CA in treating fabric.

• Food Science and Preservation
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• v.21 no.2
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• pp.157-162
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• 2014

To enhance the commercialization of fresh cut kimchi cabbage, the short-term storage effect of cut kimchi cabbage treated with $Ca^{2+}$ was studied. Cut kimchi cabbages ($3{\times}3$ cm) were treated with 2% calcium chloride (Ca), ascorbic acid (As), citric acid (Ct), and calcium chloride and citric acid (Ca/Ct), were put inside LDPE bags, and stored at $5^{\circ}C$ for 6 weeks. The weights reduced about 0.13~0.72%, and the ratio was the lowest in the Ca/Ct treatment. The reduction ratios of soluble soilds were 18.85~35.00%, and were the lowest in the Ca/Ct treatment. The titratable acidity decreased in all the treatments. The L values decreased, but a and b values of Hunter colorimeter increased in all the treatments. The preference for Ca/Ct treatment was the highest among all the treatments in the sensory evaluation. The marketing shelf-life of cut kimchi cabbage can be prolonged by the combination treatment of $Ca^{2+}$ and citric acid.

• Journal of Applied Biological Chemistry
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• v.60 no.1
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• pp.19-22
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• 2017

This study was conducted to investigate the effect of acetic acid and citric acid treatments on amount and content ratio of calcium (Ca) and phosphorus (P) which were extracted from beef shank bones. The amount of Ca in shank bone extracts significantly increased with increasing citric acid and acetic acid concentration, whereas the amount of P increased with only adding citric acid to extraction media. In the case of combined treatment with 0.2 % acetic acid and 0.1 % citric acid, the amounts of Ca and P increased to 30 and 400 %, respectively and Ca and P ratio were drastically improved from 7.53 to 1.85 compared with treatment of 0.2 % acetic acid. The sensory score of shank bone extract prepared with 0.2 % acetic acid and 0.1 % citric acid treatment showed the highest values in taste and overall acceptability among the tested shank bone extracts.

• Journal of the East Asian Society of Dietary Life
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• v.6 no.2
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• pp.195-204
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• 1996

This study was conducted to enhance the shelf-life of Kimchi and to make the unique taste of Kimchi by fermentation control. Kimchis, Prepared by win baechu soaked in 10% salt solutions containing 0.2-0.3% organic acids (OS-Kimchi), acetic acid, citric acid (CA-Kimchi), lactic acid, its mixtures and formic acid+acetic acid+fumalic acid+malic acid+citric acid(FAFMC), were examined for pH, titratable acidify, sensory evaluation, the number of total microbe and lactic acid bacteria, content of organic acids and texture during fermentation at 1$0^{\circ}C$. The decrease of pH and the increase in acidity, CA-Kimchi showed lower than those of control and various OS-Kimchi. Total microbe, lactic acid bacteria, content of lactic acid of CA-Kimchi were lower than those of control. The hardness of CA-Kimchi measured instrumentally was higher than that of control. Sensory scores of CA-Kimchi were also lower than those of control, so the Kimchi maintained good crispness and overall taste.

• Food Science of Animal Resources
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• v.35 no.5
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• pp.585-596
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• 2015

Chicken breast dipped with citric acid (CA) was treated by sous vide processing and stored in a refrigerated state for 0, 3, 6, 9, and 14 d. A non-dipped control group (CON) and three groups dipped in different concentrations of citric acid concentration were analyzed (0.5%, 0.5CIT; 2.0%, 2CIT and 5.0%, 5CIT; w/v). Cooking yield and moisture content increased due to the citric acid. While the redness of the juice and meat in all groups showed significant increase during storage, the redness of the citric acid groups was reduced compared to the control group (p<0.05). The percentage of myoglobin denaturation (PMD) of the CA groups was also increased according to the level of CA during storage. Total aerobic counts, Enterobacteriaceae counts, volatile basic nitrogen and thiobarbituric acid reactive substances (TBARS) were generally lower in the citric acid-treated samples than in untreated ones, indicating extended shelf life of the cooked chicken breast dipped in citric acid solution. The shear force of the 2CIT and 5CIT groups was significantly lower (p<0.05). The findings indicated positive effects in the physicochemical properties and storage ability of sous vide chicken breast at 2% and 5% citric acid concentrations.

• Restorative Dentistry and Endodontics
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• v.23 no.1
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• pp.379-390
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• 1998

In endodontic treatment, calcium hydroxide has been used as intracanal medicament. Although calcium hydroxide should be removed thoroughly before permanent root canal filling, no effective method for its removal has been reported. Because of irregularity of root canal walls, root curvatures and anatomic variations, it is insufficient to remove calcium hydroxide from the canal wall only by mechanical instrumentation Considering the chemical effects of irrigants on calcium hydroxide, $Ca^{++}$ dissolving effect from two calcium hydroxide products is investigated, using dis- tilled water, NaOCl, citric acid and EDTA. Vitapex$^{(R)}$ 0.1g and calcium hydroxide 0.03g were dissolved in distilled water, 5% NaOCl, 50% citric acid and 17% EDTA respectively, at 1, 3, 5, 10min. time interval. The solution was filtered using filter paper(pore size $5{\mu}m$) and $Ca^{++}$ concentration was determined by ion chromatography. The result were as follows : 1. Distilled water, NaOCl, citric acid and EDTA abstracted more $Ca^{++}$ from calcium hydroxide than Vitapex$^{(R)}$ except NaOCl 1, 5, 10 time interval. 2. EDTA and citric acid abstracted more $Ca^{++}$ from Vitapex$^{(R)}$ and calcium hydroxide than distilled water or NaOCl. The overall result support the view that water-based calcium hydroxide product is easily removed than oil-based calcium hydroxide product and EDTA, citric acid are more effective in $Ca^{++}$ elution than NaOCl or distilled water.

• Culinary science and hospitality research
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• v.5 no.2
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• pp.115-130
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• 1999

Preservative effects of natural preservatives, citric acid and salt on chopped garlic were investigated. Citric acid was very effective for the repression of bacteria multiplying and browning of chopped garlic in 0.5%~1% concentration. Salt had an effect on the repression of bacteria multiplying and browning color of chopped garlic except for 1% NaCl. Synergy effect between citric acid and NaCl was also very good for the decreasing of bacteria multiplying and the maintaining of Hunter color of chopped garlic. Compounded effect among the GF, CA and ascorbic acid was somewhat proper in the sensory evaluation of chopped garlic. And the sensory evaluation score was best in chopping size 3mm(diameter) of chopped garlic and viscosity 4500cp. of chopped garlic.

• Journal of the East Asian Society of Dietary Life
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• v.10 no.2
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• pp.153-159
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• 2000

The effect of boiling with apple vinegar and citric acid on the dissolution of Ca, Mg, and P out of pork rib bone during stew preparation was investigated. As the concentration (0, 1, 2. 4%) of apple vinegar and citric acid increased, the amount of Ca, Mg, and P dissolved out of the rib bone increased compared with the control. The increase in boiling time(3, 6, 9, 12 hour) also showed the same result. Between the two acid condiments citric acid extracted more Ca, Mg, and P than the apple vinegar at the same concentration. The pH of the pork rib bone stew added with the acid condiments increased gradually during the boiling process. Between the two acid condiments the apple vinegar extracted more amino acids and protein than citric acid at the same concentration.

• Journal of Fashion Business
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• v.13 no.1
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• pp.115-124
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• 2009

Chitosan and CA/BTCA were employed in order to induce crosslinking in the fiber for the improvement of wrinkle recovery of the cotton fabrics and the endowment of anti-microbial functions to the fabric. The treated fabrics were dyed by using reactive dyestuff and their dyeing behaviors were investigated. As a result, the fabric treated with chitosan only exhibited more dye-uptake amount than the untreated fabric, and the treated and untreated fabrics together showed excellent light-fastness and wash-fastness. In the cases that CA or BTCA was added to the chitosan, the CA-treated showed better dye-uptake and dyeing properties as light-fastness than the BTCA-treated. In conclusion, it is possible to maintain the dye-uptake level at reduced treatment cost when the CA is employed as a substitute cross-linking agent for BTCA.

• KSBB Journal
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• v.10 no.1
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• pp.78-88
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• 1995

The encapsulatpd A. niger grew up inside the capsule and mycelia penetrated through the pore of the capsule membrane. The mycelia on the capsule wall became loose when the carbon source and oxygen were deficient in the medium. On the contrary, the production rate increased and mycelia made a lump tightly when the carbon source and oxygen were sufficient. Namely, number of proper capsule of unit volume in the medium was existed. The phenomenon which was swelled of capsule membrane in cultivation could prevented by adding CaCl2 into the medium. According to the time adding CaCl2 into the medium, the production rate of citric acid was influenced. In case of adding CaCl2 into the medium at 7th day cultivation, the production yield of citric acid was increased about 40 percent higher than that of adding CaCl2 initially. The production yield of citric acid using encapsulated A. niger of flask culture was influenced with oxygen supply. The production yield of citric acid ($\Delta$p/$\Delta$s) of the flask culture was increased 3.88 time by using T-flask instead of parafilm sealed flask. Therefore, the productivity and consumption rate concerning production which was taken carbon source were increased when oxygen supply was sufficient. The production of citric acid using encapsulated A. niger was increased average 30 percent higher than that of bead in between 6th and 13th day cultivation.