• KOREAN JOURNAL OF CROP SCIENCE
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• v.57 no.1
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• pp.29-34
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• 2012

The objective of this study was to rapidly evaluate fatty acids in a collection of millet (Panicum miliaceum subsp. miliaceum) of different origins so that this information could be disseminated to breeders to advance germplasm use and breeding. To develop the calibration equations for rapid and nondestructive evaluation of fatty acid content, near-infrared reflectance spectroscopy (NIRs) spectra (1104-2494 nm) of samples ground into flour ($n$=100) were obtained using a dispersive spectrometer. A modified partial least-squares model was developed to predict each component. For foxtail millet germplasm, our models returned coefficients of determination ($R^2$) of 0.89, 0.89, 0.89, and 0.92 for palmitic acid, oleic acid, linoleic acid, and total fatty acids, respectively. The prediction of the external validation set (n=10) showed significant correlation between references values and NIRs values ($r^2$=0.64, 0.90, 0.79, and 0.89 for palmitic acid, oleic acid, linoleic acid, and total fatty acids, respectively). Standard deviation/standard errors of cross-validation (SD/SECV) values were close to 3 (2.62, 2.40, 1.85, and 2.23 for palmitic acid, oleic acid, linoleic acid, and total fatty acids, respectively). These results indicate that these NIRs equations are functional for the mass screening and rapid quantification of the oleic and total fatty acids characterizing millet germplasm. Among the samples, IT153514 showed an especially high content of fatty acids ($48.14mg\;g^{-1}$), whereas IT123909 had a very low content ($34.44mg\;g^{-1}$).

• Korean Journal of Food Science and Technology
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• v.51 no.4
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• pp.301-308
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• 2019

The antioxidant properties of Eriobotrya japonica leaf extract were investigated using DPPH and ABTS radical scavenging assay. The 80% ethanol extract of leaves ($IC_{50}$ values for DPPH and ABTS were 13.9 and $10.9{\mu}g/mL$, respectively) and young leaves ($IC_{50}$ values for DPPH and ABTS were 20.7 and $17.3{\mu}g/mL$, respectively) showed high radical scavenging activity. Additionally, the quantitative method for estimation of ellagic acid and chlorogenic acid from E. japonica leaves was optimized by HPLC/DAD. This method showed high linearity of the calibration curve with a coefficient of correlation ($R^2$) equal to 0.999. The LOD values for ellagic acid and chlorogenic acid were 2.35 and $0.73{\mu}g/mL$, respectively, whereas LOQ values were 7.13 and $2.22{\mu}g/mL$, respectively. Recovery of the two compounds was 99.7-108.0% with RSD values less than 5.31%. These results suggest that 80% ethanol extract of E. japonica leaves could serve as a potential source of natural antioxidant for us in various industrial applications.

• Culinary science and hospitality research
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• v.22 no.2
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• pp.57-65
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• 2016

This study aimed to evaluate quality characteristics of soy sauce by various manufacturing methods. We examined color values, contents of saccharide and free amino acid. Regarding color values, brewed soy sauce showed lower level of L-values than traditional soy sauce, and the L-value was increased with time dependent manner in traditional soy sauce. The one year old traditional soy sauce exhibited the lowest a-value whereas the three years old traditional soy sauce showed the highest b-value (+4.27). The content of the bitter and savory taste amino acids was the highest in commercial soy sauce with the values of 28.98% and 18.93%, respectively. In addition, traditional soy sauce contained more GABA than brewed soy sauce.

• Journal of the Korean Society of Food Science and Nutrition
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• v.26 no.3
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• pp.422-429
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• 1997

For the complete and accurate amino acid determination of protein and food samples, 3 different hydrolysis procedures have been conducted in parallel for each sample, which include the alkaline hydrolysis for tryptophan determination, performic acid oxidation prior to the acid hydrolysis for the determination of cysteine and cystine, and the 6N HCl hydrolysis for the determination of the rest of amino acids. In the present study, amino acid concentrations obtained from the modified single hydrolysis procedure were compared with the values from the conventional hydrolysis procedures in casein and nine food and composite dish samples. In most of the samples tested, the modified single hydrolysis procedure gave significantly higher values of cysteins and cystein compared to the performic acid oxidation method, but resulted in a considerable destruction of tryptophan in food and composited dish samples. There was no consistent difference in the rest of amino acid concentrations between the two hydrolysis systems. Therefore, for complete amino acid determination of various foods and composite dishes, the single hydrolysis method may replace the 6N HCl hydrolysis and performic acid oxidation methods, and thereby reduces 3 hydrolyses to 2 steps with much higher recoveries of the sulfur containing amino acids.

• Journal of Food Hygiene and Safety
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• v.14 no.1
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• pp.27-33
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• 1999

Phytic acid, making up 1~5% of the composition of many plant seeds and cereals, is known to form iron-chelates and inhibit lipid peroxidation. Thiobarbituric acid reactive substances (TBARS), as an indication of lipid peroxidation, were measured in beef round, chicken breast, pork loin, and halibut muscle after the meats were stored for 0, 1, 3, 5, and 7 days at various temperatures [frozen (~2$0^{\circ}C$), refrigerator (4$^{\circ}C$), and room temperature ($25^{\circ}C$)]. Phytic acid effectively inhibited lipid peroxidation in beef round, chicken breast, halibut, and pork loin muscle (p<0.05). The inhibitory effect of phytic acid was dependent on concentration, storage time, and temperature. At frozen temperature, the inhibitory effect of phytic acid was minimal, whereas at room temperature, the inhibitory effect of phytic acid was maximal, probably due to the variation of the control TBARS values. At the concentration of 10 mM, phytic acid completely inhibited lipid peroxidation in all the muscle foods by maintaining TBARS values close to the level of the controls, regardless of storage time or temperature (p<0.05). The rate of lipid peroxidation was the highest in beef round muscle, although they had a close TBARS value at 0 day. Addition of phytic acid to lipid-containing foods such as meats, fish meal pastes, and canned seafoods may prevent lipid peroxidation, resulting in improvement of the sensory quality of many foods and prolonged shelf-life.

• Environmental Sciences Bulletin of The Korean Environmental Sciences Society
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• v.2 no.2
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• pp.139-148
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• 1998

The charge densities of humic acid and humic extract have been determined by back titration using spectrophotometry as the method of end point detection and several cationic polymers of different charge density(copolymers of acylamide and dimethylaminoethylacrylate and polydiallyidimethylammonium chloride, PDDA), and a cationic indicator o-toluidine blue(o-Tb). The charge densities of humic acid and humic extract obtained depend on the charge densities of cationic polymers used. When the polymers of lower charge density are used, lower apparent charge density values are obtained, but for polymers of high charge density(above 2.5 meq/g), the measured values are almost identical, but also are nearly the same as that obtained for PDDA which has a high charge density(about 6 meq/g). For polymers of lower charge density, it is considered that the optimum dosage does not correspond to 1 :1 charge neutralization between anionic and cationic groups. Polymers of high charge density should be used in order to achieve a complete charge neutralization. As humic acid and humic extract are dissociable acids, their ionization is heavily pH dependent and so higher charge density values are obtaines with increasing pH.

• Journal of environmental and Sanitary engineering
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• v.4 no.2 s.7
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• pp.91-99
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• 1989

An anaerobic acidogenic fermentation experiment was carried out in order to investigate the distribution of volatile acid products and gas generations with varing temperatures and pH values. The experiment was carried out using $1\%$ glucose as substrate and a pair of 3.5 liter vessle as bench scale batch reactors. The reactors were operated for 7 days at 25, 30 and $35^{\circ}C$ and at pH values of 4.0, 4.5, 5.0, 5.5 and 6.0 at each temperature conditions. Major products at all experiment pH's at $35^{\circ}C$ were acetic acids and butyric acids which together composed around $90^{\circ}F$ of total product acids. At higher pH values at $35^{\circ}C$, propionic acid reached around $10\%$. At all experiment conditions, 52 to $55\%$ of generated gases comprised of hydrogen gas and 45 to $48\%$ of carbon dioxide. With temperature increase from 25 to $35^{\circ}C$, the production rate of acetic acid increased 2.9 fold, butyric acid 22 fold, hydrogen gas 2.0 fold and carbon dioxide gas 2.3 fold. Optimum reaction conditions for highest production of acetic acid and hydrogen gas was determined to be pH 5.5 at $35^{\circ}C$.

• Journal of Fashion Business
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• v.20 no.3
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• pp.119-132
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• 2016

Weighting of silk fabrics have long been practiced in silk fabric trading based on the primary consideration of price-weight, and secondary one of quality improvement in handle, luster, and drape properties. Recent trend of practicing weighting of silk fabrics is, however, focused on the improvement of the handle, luster, drape, and other properties. During the finishing processes of synthetic fiber, nylon, comprising amide structure, include the use of tannic acid, especially in the dyeing. A multitude of studies are being implemented in terms of improving fastness to washing, fastness to light of dyed nylon product, or the light fastness of nylon 6 itself. In this study, the effects of various tannic acid treatments on the physical properties related to the handle of nylon 6 and silk fabrics are examined and reviewed. The effects of treatment condition of the tannic acid, e.g., the concentration of the aqueous tannic acid solution, treatment time, and temperature were investigated. As the concentration of the aqueous solution of tannic acid increased, the bending rigidity values of the silk and nylon 6 fabrics increased. The treated fabrics felt stiff to the touch. Within the mild conditions of bending employed in the bending measurement of KES, nylon 6 treated fabric specimen exhibited a trend of improvement of bending resiliency within the range of small bending deformation. The weight of treated fabrics have all increased. The air-permeability values decreased as the treatment concentration increased. However, the decrease tendency of air permeability values may be alleviated by adjusting the fabric count during the tentering or expanding processes, either by tension adjustment or heat treatment. Optimum conditions of the treatment for nylon 6 are 1.25% tannic acid concentration, bath temperature of $85^{\circ}C$, pH 3.1, and those for silk fabric treatment are 1.25% tannic acid concentration, bath temperature of $85^{\circ}C$, pH 3.1. The treatment conditions will lead to the improvement in the properties of fabrics for summer.

• Korean journal of food and cookery science
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• v.10 no.2
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• pp.161-165
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• 1994

It was aimed to investigate the effects of caffeic acid on the rates of Maillard reaction. The rates of browning reaction increased as the browning temperature increased. The color intensity of the browning mixtures indicated to depend on the amino acid rather than reducing sugar. Also, the color intensity of the browning mixtures increased more rapidly in the presence of caffeic acid. The increase in color intensity seemed to depend mainly to the polymerization of o-quinones formed from caffeic acid. The caffeic acid, furthermore, appeared to enhance the color intensity of the browning mixtures through the interaction with amino acid, especially methionine and phenylalanine. The activation ener-gies of the browning reaction without caffeic acid were 108∼130 J/mol, and Q10 values were 2.6∼3.2. The activation energies and Q10 values of browning mixtures decreased in the presence of CA. The activation energies of the browning mixtures with caffeic acid were 90∼101J/mol, and Q$\_$10/ values were 2.0∼2.6.

• Food Science of Animal Resources
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• v.33 no.1
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• pp.58-66
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• 2013

In this study, the effect of packaging methods [aerobic packaging (AP), vacuum packaging (VP) and modified atmosphere packaging (MAP: 75% $N_2$, 25% $CO_2$)] on colour, lipid quality and microbial growth of beef patties enhanced with flaxseed flour was investigated during storage at $2{\pm}1^{\circ}C$ for 10 d. L and a values of beef patties packaged in MAP and VP were higher (p<0.05) than that of the samples packaged in AP. Packaging in MAP and VP retarded the lipid oxidation (TBA value) and inhibited the bacterial growth of beef patties enhanced with flaxseed flour. Furthermore, TBA values in beef patties were correlated with a values (r = -0.340; p<0.05). Packaging in MAP was more effective than packaging in VP for inhibiting microbial growth. The samples packaged in VP lost their shape due to the compression by external atmosphere. Packaging treatment had no significant effect on saturated fatty acid (SFA), monounsaturated fatty acid (MUFA) and polyunsaturated fatty acid (PUFA) levels in beef patties. The a and b, TBA and MUFA values changed during storage time. TBA values for beef patties increased during storage time, but did not reach to the limit value (1 mg/kg) until the end of the storage time. The results suggest that the shelf life of beef patties enhanced with flaxseed flour can be extended by packaging in MAP.