• Journal of Applied Biological Chemistry
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• v.62 no.4
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• pp.407-415
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• 2019

The biological half-life of pesticides applied on crops is the key indicator for ensuring the safety of agricultural products. The biological half-life is affected by the several factors like growing conditions of the crop, climate, application method, and physicochemical properties of pesticides. In this study, the biological half-life was calculated and the degradation rates of six triazole fungicides sprayed on perilla leaves were evaluated. Moreover, the statistical analysis confirmed the correlation between the biological half-life and physicochemical properties of six triazole pesticides. The recoveries of the six pesticides were between 84.8-104.9%, which satisfied the residual pesticide analysis criteria. The biological half-life of six pesticides sprayed on perilla leaves, calculated using the first-order kinetics model, ranged between 6.4-15.1 days. When the biological half-life and the physicochemical properties were correlated using the principal component analysis: pKa and Log P, the biological half-life was found to be affected by PC1. The correlation coefficient between biological half-life and physicochemical properties (pKa), calculated by Spearman rank-order correlation, was R² = -0.928 (p <0.01). Biological half-life has been shown to correlate with pKa. In conclusion, it can be used as a database for the relationship between biological half-life and physicochemical properties and will contribute to ensure safe supply of agricultural products.

• Korean journal of food and cookery science
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• v.12 no.3
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• pp.273-278
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• 1996

To investigate the main components of Korean traditional soy sauce for its typical taste, we compare the physicochemical properties of Korean traditional soy sauce and commercial soy sauce. The physicochemical analysis revealed that each components showed significant difference between Korean traditional soy sauce and commercial soy sauce. The significant characters for discrimination between Korean traditional soy sauce and commercial soy sauce were salt content, ammonia nitrogen content and total acidity (R$^2$=0.99). The components of Korean traditional soy sauce divided into 3 clusters, and each group is characterized as formol nitrogen, salt and total nitrogen content by cluster analysis. Main amino acids of Korean traditional soy sauce were alanine, glutamic acid, leucine and valine.

• Food Science and Biotechnology
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• v.16 no.5
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• pp.663-674
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• 2007

Starches from different botanical sources differ in the ratio of amylose to amylopectin contents, molecular structures of amylose and amylopectin, granule morphology, and minor-component contents. These structural features result in different gelatinization, pasting, retrogradation properties, and enzyme digestibility of starch granules. In this review, compositions and molecular structures of starches and their effects on the physicochemical properties are summarized and discussed.

• Food Science of Animal Resources
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• v.39 no.2
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• pp.286-295
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• 2019

Red pepper seed (RPS) is commonly removed during the production of red pepper powder, which is contains large amounts of dietary fibers and is abundant in nutrients, readily available. In this study, we determined the effects of adding RPS powder on the physicochemical properties of emulsified meat products. Meat emulsion samples were prepared with pork hind leg meat (60%) and back fat (20%), iced water (20%), various additives, and RPS powder at different concentrations [0% (control), 1%, 2%, 3%, and 4%]. For the physicochemical properties, moisture and fat content, pH value, color, emulsion stability, cooking yield, appearance viscosity, and textural properties were examined. Addition of RPS induced significantly higher values in moisture content, pH, cooking yield, and a* values of the meat emulsion samples, regardless of the amount added. However, lower values were obtained for emulsion stability, cooking yield, and viscosity in samples with RPS powder at 3% or 4% among all groups. In general, addition of RPS powder at 1% and 2% led to the greatest values in viscosity of the meat emulsion samples. Higher values (p<0.05) in hardness and springiness were observed in samples with RPS powder at 4% and 3%, respectively. For gumminess, chewiness, and cohesiveness, the addition of RPS powder at 1%, 2%, and 3% induced the highest values (p<0.05) in the meat emulsion samples. These results showed that addition of RPS powder at optimum levels (2%) could be utilized to improve quality properties of emulsified meat products as a non-meat ingredient.

• The Korean Journal of Food And Nutrition
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• v.14 no.6
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• pp.596-604
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• 2001

Twelve varieties of Korean rice and ten varieties of Japanese rice were selected. After being milled. they were analyzed about various physicochemical properties such as moisture, protein and amylose, a -amylase activity, gelatinization properties. And after being cooked with proper amount of water texture and other physical properties were measured by Texturometer, Tensipresser and Rheolograph-micro. Finally the sensory evaluation test was carried out. The results were as follows. 1. In case of protein contents, amylose contents and $\alpha$-amylase activity, Korean rice had a slightly higher value than Japanese As a consequence. Korean rice showed a little stronger hardness and a little weaker stickiness compared with Japanese rice. 2. Amylose contents showed very high correlation with other physicochemical properties and peak viscosity and gelatinization temperature of RVA, the ratio of stickiness to hardness( -Hl/Hl ) of Texturometer and the tan $\delta$(the ratio of dynamic loss to dynamic viscoelasticity) of Rheolograph-micro showed high correlation with other analyzed properties. 3. The ( -/+)work balance of low compression test(25% ) of Tensipresser analysis(texture analysis on the surface of cooked rice) and tan f of Rheolograph-micro showed very high correlation with sensory evaluation results. By using this parameters as major independent variables, some trials to derive high confidence multiple regression equations were accomplished. By the equations it would be possible to make an approximate pre-estimate of eating quality for unknown japonica rice.

• Korean journal of food and cookery science
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• v.27 no.2
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• pp.9-17
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• 2011

In this study, the physicochemical properties of polished rice flour, brown rice flour, and Jeung-pyun dough were studied. The protein, lipid, dietary fiber, pH of brown rice flour were higher than those of polished rice flour. The total polyphenol contents and electron donating ability (EDA) of brown rice flour (83.60 mg%, 2.44%, respectively) were higher than those of polished rice flour (56.91 mg%, 1.43%, respectively). The temperature gelatinization of brown rice flour higher than that of polished rice flour. The counts in Jeung-pyun dough were not significantly decreased brown-rice flour. The addition of brown rice flour decreased the amount of carbon dioxide gas evoluted from Jeung-pyun dough. The pH values of brown rice Jeung-pyun dough generally decreased fermentation time.

• Journal of the East Asian Society of Dietary Life
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• v.20 no.1
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• pp.69-76
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• 2010

This study was performed to examine the effects of salt addition level on changes in the physicochemical properties and color values of salted shrimp during fermentation. Fresh shrimp were salted with different concentrations (8, 18, 28%) of Chunil salt and fermented at $20^{\circ}C$ for 160 days. In the 8% salted shrimp treatment, volatile basic nitrogen (VBN), amino nitrogen (AN), and trimethylamine (TMA) contents rapidly increased during the fermentation period, while in the 18 and 28% salt groups these increases were reduced throughout the 160 days of fermentation. Thiobarbituric acid (TBA) values increased rapidly for 120 days of fermentation and then decreased. The thiobarbituric acid values of the 18, and 28% salted and fermented shrimp groups were lower than the that of the 8% group. In addition, Hunter's color L, a, and b values decreased as the fermentation period increased.

• Korean journal of food and cookery science
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• v.18 no.3
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• pp.340-348
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• 2002

Changes in the physicochemical properties of frying oil after single or repeated use in foodservice establishments were studied. The experiment was designed to simulate the practical frying practice based on a survey from the dieticians in the food service establishments. Used oils came from the single frying of mackerel and the sequential frying of 1) potato and mackerel, 2) battered pork and mackerel, and 3) potato, battered pork, and mackerel. The used oil samples were analyzed and compared with the fresh one. Oil quality parameters such as acid value, peroxide value, thiobarbituric acid value, iodine value, viscosity, and color were measured at each step of deep-fat frying. The physicochemical properties of the frying oils have been more or less affected by the frying conditions. However, the used oils resulted from the experimental trials were within the range of acceptance as indicated by the acid and peroxide values.

• The Korean Journal of Food And Nutrition
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• v.23 no.1
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• pp.114-117
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• 2010

The effects of isolated soy protein(ISP) content on the physicochemical properties of extrudates from rice flour produced by a single-screw extruder were evaluated. The integrity index(II), nitrogen solubility index(NSI), rehydration ratio(RR), and density were measured as indices of the changes of physicochemical properties of rice extrudates. Increased amounts of ISP resulted in increased II but decreased RR and density. There was no change in the NSI value. It was concluded that the addition of ISP to the raw material could be helpful in texturization of rice extrudate.

• Journal of the Korean Society of Food Science and Nutrition
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• v.26 no.5
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• pp.886-891
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• 1997

The interrelation between physicochemical properties of milled rice and retrogradation of rice bread during cold storage was examined to compare the varietal difference in maintenance of rice bread quality. Twelve rice materials showed big varietal difference on physicochemical properties of rice starch such as amylose content(0.0~29.2%), gel consistency(20~98mm), and alkali digestion value(2.0~7.0). Rice bread made from milled rice of Jungwonbyeo, AC 27 and IRAT 177 exhibited soft texture and late retrogradation of rice bread during cold storage(4$^{\circ}C$). The amylose content of milled rice was closely associated with gel consistency negatively and with springiness of rice bread positively. The retrogradation of rice bread texture during cold storage was correlated with gel consistency of rice flour positively and with alkali digestion value of milled rice negatively.