• The Korean Journal of Food And Nutrition
• /
• v.11 no.3
• /
• pp.329-333
• /
• 1998

The effects of 0.5%(v/v) acetic acid (AA), 0.5%(v/v) lactic acid(LA), or 0.5%(v/w) citric acid(CA) on gram-negative bacterial counts (GNC) and aerobic plate counts (APC) in flatfish strips stored at 4$^{\circ}C$ or 1$0^{\circ}C$ were assessed. Treatments of 0.5% AA were completely (P<0.05) inhibited GNC compared to the initial controls for 12 days at 4$^{\circ}C$. Treatments of either LA or CA rapidly increased GNC compared to those of AA after 9 days at 4$^{\circ}C$. Treatments of AA were microbiological acceptable for 6 days at 1$0^{\circ}C$, but those of LA and CA did not lasted. AA treatments were completely (P<0.05) inhibited aerobic spoilage bacteria (APC) compared to the initial controls for 6 days at 4$^{\circ}C$. Treatments containing either 0.5% LA or 0.5% CA were ineffective after 9 days at 4$^{\circ}C$ and 3 days at 1$0^{\circ}C$, respectively. Based on these results, AA treatment was the most effective for suppressing the growth of aerobic spoilage bacteria during storage at both 4 and 1$0^{\circ}C$. Flatfish strips treated with 0.5% AA extended microbiological shelf-life for 12 days at 4$^{\circ}C$.

• Food Science and Biotechnology
• /
• v.17 no.1
• /
• pp.114-117
• /
• 2008

Chelating agents to sand lance fish sauce for the prevention of precipitate formation were applied. The precipitates consisted of crude protein (74.4%), ash (18.7%), and other components (6.9%). Sand lance sauce was mainly composed of glutamic acid (3.69 mg/g), alanine (2.96 mg/g), and lysine (2.64 mg/g). However, there was an increase in the amount of hydrophobic amino acids, phenylalanine, isoleucine, and leucine, in the precipitates. Sodium ions were not detected in the precipitate; rather, the main elements were Mg ($1.98{\times}10^4\;{\mu}g/g)$, K ($1.36{\times}10^4\;{\mu}g/g)$, and Ca ($6.66{\times}10^2\;{\mu}g/g)$. In HPLC analysis, fish sauce was composed of 2 main peaks with molecular weights of 85.5 and 528.4 Da, respectively. However, the precipitate contained one peak with a molecular weight of 1,513.5 Da. The addition of 0.2% malic acid and citric acid caused 55 and 70% prevention of the precipitate, respectively. Citric acid was the most effective chelating agent and efficiently prevented precipitation in the fish sauce.

• KOREAN JOURNAL OF CROP SCIENCE
• /
• v.41 no.6
• /
• pp.729-735
• /
• 1996

This study was carried out to investigate the effect of Germaniwn(Ge) treatment in the culture media on the Ge absorption by the callus induced from brown rice cv. Dongjinbyeo. MS medium was more effective on the growth ratio of callus and the content of Ge and some inorganic elements except K in callus than N$_{6}$ medium. The more Ge treatment in the N$_{6}$ or MS medium, the more Ge absorption by the callus, but the growth ratio of callus and the content of Ca, Mg, and K in callus were decreased. The content of Fe, Mn, Zn, and Cu was increased under treatment up to 100～200mg /$\ell$ Ge, but tended to be decreased under treatment more than that of Ge concentration. Under treatment less than 150mg /$\ell$ Ge, GeO$_2$(inorganic Ge) was more effective on the Ge absorption by callus than Ge-132(organic Ge), but Ge-132 was more effective on the Ge ab-sorption by callus and the activity of callus in case of treatment more than 150mg /$\ell$ Ge. The lower pH of culture medium, the higher Ge content in the callus. When callus was cultured on medium supplemented with Ge and 0.1～1.0mM of citric acid or myo-inositol, content of Ge and some inorganic elements in callus, as well as growth and dry weight of callus, were tend to increase in comparison to control, but myo-inositol was more effective on them than citric acid.cid.

• Restorative Dentistry and Endodontics
• /
• v.41 no.1
• /
• pp.12-21
• /
• 2016

Objectives: To evaluate the effects of three acids on the microhardness of set mineral trioxide aggregate (MTA) and root dentin, and cytotoxicity on murine macrophage. Materials and Methods: OrthoMTA (BioMTA) was mixed and packed into the human root dentin blocks of 1.5 mm diameter and 5 mm height. Four groups, each of ten roots, were exposed to 10% citric acid (CA), 5% glycolic acid (GA), 17% ethylenediaminetetraacetic acid (EDTA), and saline for five minutes after setting of the OrthoMTA. Vickers surface microhardness of set MTA and dentin was measured before and after exposure to solutions, and compared between groups using one-way ANOVA with Tukey test. The microhardness value of each group was analyzed using student t test. Acid-treated OrthoMTA and dentin was examined by scanning electron microscope (SEM). Cell viability of tested solutions was assessed using WST-8 assay and murine macrophage. Results: Three test solutions reduced microhardness of dentin. 17% EDTA demonstrated severe dentinal erosion, significantly reduced the dentinal microhardness compared to 10% CA (p = 0.034) or 5% GA (p = 0.006). 10% CA or 5% GA significantly reduced the surface microhardness of set MTA compared to 17% EDTA and saline (p < 0.001). Acid-treated OrthoMTA demonstrated microporous structure with destruction of globular crystal. EDTA exhibited significantly more cellular toxicity than the other acidic solutions at diluted concentrations (0.2, 0.5, 1.0%). Conclusions: Tested acidic solutions reduced microhardness of root dentin. Five minute's application of 10% CA and 5% GA significantly reduced the microhardness of set OrthoMTA with lower cellular cytotoxicity compared to 17% EDTA.

• Journal of the Korean Society of Food Science and Nutrition
• /
• v.18 no.1
• /
• pp.101-108
• /
• 1989

In order to determine optimal conditions for the preparation of Japanese apricot wine, the changes in major components were experimented during ripening. A weight was $18.3{\pm}2.57\;g$ at June 22 or so. Moisture was reached $92.1{\pm}0.17\;%$ at that time. Respiration amounts were decreased by degrees during the ripening of Japanese apricot but came near climacteric maximum state about June 22. pH was decreased from $2.76{\pm}0.025$ to $2.51{\pm}0.081$, titratible acidity was increased from $1.15%{\pm}0.083%$ to $1.39{\pm}0.061%$. Fe was detected most of all and Zn, Mg, Cu and Ca were checked by the next order in mineral contents. And the rate of mineral contents was decreasing phenomenon slightly with ripening. Total sugar, about June 8, was higher than any other time with $1.74{\pm}0.090%$ and reducing sugar was increased with similarly a tendency of total sugar. Malic and citric acid were much of organic acids. The content of malic acid was decreased greatly but ctric acid was increased during ripening.

• Food Science and Preservation
• /
• v.19 no.4
• /
• pp.485-491
• /
• 2012

This study was conducted to investigate the pH, soluble solid contents, color difference, mineral contents, free sugar contents, and sensory quality of infrared- and cold-air-dried peaches. The pH, soluble solid contents, and free sugar contents of the infrared-dried peaches were higher than those of the cold-air-dried peaches. In the Hunter's color value, the L and ${\Delta}E$ values of the infrared-dried peaches were higher than those of the cold-air-dried peaches; but the a and b values of the cold-air-dried peaches were higher than those of the infrared-dried peaches. The major organic acids of the dried peaches were citric acid, malic acid, and oxalic acid. The minerals with the highest to lowest contents, in that order, were K, Mg, Ca, Na, Fe, Zn, Cu, and Al. The mineral contents of the cold-air-dried peaches were higher than those of the infrared-dried peaches. The appearance and taste of the infrared-dried peaches were better than those of the cold-air-dried peaches. These results indicate that infrared drying is the effective drying method for the production of high-quality dried peaches.

• Applied Biological Chemistry
• /
• v.43 no.2
• /
• pp.106-109
• /
• 2000

In order to determine the optimum harvest time of Acanthopanax koreanum Nakai, free sugars, organic acids, amino acids and minerals were investigated. Ash, crude fat and crude protein of 4-age's tree of Acanthopanax koreanum were $2.98%{\sim}3.90%,\;1.93%{\sim}2.34%,\;3.52%{\sim}4.23%$, respectively. Minerals were 835.9 mg/100g of K, 971.3 mg/100g of Ca, 168.7 mg/100g of Mg, 38.8 mg/100g, of Na, 18.6 mg/100g of Fe, and 8.5 mg/100g of Cu on average, respectively. Calcium content was increased distinguishably as late as harvest time, especially in stem and root. Glucose, fructose and sucrose content of stem were $0.71{\sim}0.75%,\;0.31{\sim}0.03%,\;and\;0.16{\sim}0.21%$, respectively. Organic acid was $381.0\;mg/100g{\sim}504.9\;mg/100g$, and was mainly consisted of succinic acid, citric acid and malic acid. Twelve kinds of free amino acids were detected. Total amino acids was $33.56\;mg/100g{\sim}48.60\;mg/100g$, and it was the highest on samples harvested at September. Arginine, phenylalanine and glutamic acid were the main free amino acids of stems.

• Korean Journal of Food Science and Technology
• /
• v.32 no.1
• /
• pp.37-41
• /
• 2000

This study has been carried out to investigate the chemical composition of Acorus calamus L., a wild plant (Chang Po) which has long been used as a medicine or a hair rinse in Korea and China. Potassium was found to be the most predominant mineral in leaf and root, followed by calcium, magnesium, and phosphorus, in a decreasing order. Contents of potassium in leaf and root account for 54a.65 mg% and 242.87 mg%, respectively. Contents of these minerals in leaf were higher value than that in root. Glucose and fructose were found to be the major free sugars in leaf and root. Malic acid was the most abundant organic acid of leaf and root, and followed by citric acid. Fourteen different kinds of fatty acids were identified from the leaf and root. Content of unsaturated fatty acids. such as linolenic, and linoleic acid ware higher than that of saturated fatty acids. Content of total amino acids was 3 times higher in leaf than that in root. Leucine was the major amino acid in leaf and glutamic acid in root.

• Food Science and Preservation
• /
• v.6 no.4
• /
• pp.475-480
• /
• 1999

The chemical components in different parts such as seed, cotyledon, hull, pod, leaf, stem and root of Korean sword bean(Canavalia gladiata) were determined in this study. The contents of total sugar and protein were relatively higher in cotyledon than other parts. The highest mineral component was K, Ca in root and leaf, respectively. In case of organic acids, relatively higher content of oxalic acid(2,556 mg%), citric acid(573 mg%) was found in leaf and pod, respectively. Among free sugars, the contents of sucrose(3.80%), fructose(2.17%) were the highest contents in hull and stem, respectively. The highest component total amino acids in cotyledon and leaf, pod, stem, and root was glutamic acid(592 mg%), glutamic acid(429 mg%), proline(497 mg%), lysine(328 mg%) and arginine(714 mg%), respectively. Among fatty acids in hull and pod, palmitic acid(32.75%, 21.93%) was high in saturated fatty acid fraction, while linoleic acid(39.15%, 43.03%) was high in polyunsaturated fatty acid fraction.

• Food Science and Preservation
• /
• v.7 no.2
• /
• pp.189-194
• /
• 2000

To study the potential of the Zanthoxylum schinifolium and Z. piperitum leaves, as raw materials for functional food and medicine, apart from male and female, chemical components were carried out. Among general components of sancho and chopi leaves, moisture and crude protein were higher sancho leaf than chopi leaf, but total sugar and crude fat were higher chopi leaf than sancho leaf and the components of major minerals were K, Ca, Mg and Na. Among free sugars, glucose(0.24% and 0.21%) and sucrose(0.19% and 0.27%) were the highest contents in sancho and chopi leaves(male and female), respectively. The organic acid were isolation and identification as malic acid and citric acid, citric acid is higher than malic acid. The total amino acid of sancho and chopi leaves contained proline and glutamic acid in male and female sancho and female chopi leaves, glutamic acid and aspartic acid in male chopi leaf highly in order. The fatty acid contents of four samples were high 15.16%, 9.76%, 8.78% and 9.29% of linolenic acid, respectively. Among many volatile compounds, limonene(13.25% and 19.16%) and citronellal(34.37% and 29.66%) were predominant flavor compounds in sancho and chopi leaves(male and female), respectively.