• Journal of the Korean Society of Food Culture
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• v.38 no.5
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• pp.356-364
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• 2023

This study compared the physicochemical properties of soybean curd residue and black soybean curd residue produced by hot air-drying and freeze-drying. Regardless of drying method, the crude protein, crude ash, crude fiber contents, pH, L, a, b color values and water soluble index were higher in soybean curd residue, whereas total polyphenol contents and antioxidant activity were higher in black soybean curd residue. Significant differences in water absorption index, oil absorption capacity and emulsion activity were observed between soybean curd residue and black soybean curd residue in freeze-drying. On the other hand, the emulsion stability was not significant difference in both hot-air drying and freeze-drying. The crude protein and crude fiber contents of soybean curd residue were not significant difference between hot-air drying and freeze-drying. Freeze-drying resulted in higher crude ash contents, pH, water absorption index, water soluble index, oil absorption capacity, emulsion activity and emulsion stability than hot-air drying. Hot-air drying have caused significantly higher water contents, water activity, total polyphenol contents and antioxidant activity in soybean curd residue than freeze-drying. In conclusion, soybean type and drying methods affect the physicochemical and quality characteristics of soybean curd residue, which could be important factors in the manufacture of processed foods.

• Food Science of Animal Resources
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• v.38 no.2
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• pp.315-324
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• 2018

The objective of this study was to evaluate the efficacy of alkaline-treated sugarcane bagasse fiber on physicochemical and textural properties of meat emulsion with different fat levels. Crude sugarcane bagasse fiber (CSF) was treated with calcium hydroxide ($Ca(OH_2)$) to obtain alkaline-treated sugarcane bagasse fiber (ASF). The two types of sugarcane bagasse fiber (CSF and ASF) were incorporated at 2% levels in pork meat emulsions prepared with 5%, 10% and 20% fat levels. Alkaline-treatment markedly increased acid detergent fiber content (p=0.002), but significantly decreased protein, fat, ash and other carbohydrate contents. ASF exhibited significantly higher water-binding capacity, but lower oil-binding and emulsifying capacities than CSF. Meat emulsions formulated with 10% fat and 2% sugarcane bagasse fiber had equivalent cooking loss and textural properties to control meat emulsion (20% fat without sugarcane bagasse fiber). The two types of sugarcane bagasse fiber had similar impacts on proximate composition, cooking yield and texture of meat emulsion at the same fat level, respectively (p>0.05). Our results confirm that sugarcane bagasse fiber could be a functional food ingredient for improving physicochemical and textural properties of meat emulsion, at 2% addition level. Further, the altered functional properties of alkaline-treated sugarcane bagasse fiber had no impacts on physicochemical and textural properties of meat emulsions, regardless of fat level at 5%, 10% and 20%.

• Korean journal of food and cookery science
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• v.32 no.4
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• pp.524-530
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• 2016

Purpose: The properties of starch and starch gel prepared from a newly inbred sweet potato, Daeyumi were compared to the properties of starch and starch gel prepared from Sinyulmi which is a well known mealy type sweet potato. Methods: The starch was isolated by using the alkaline steeping method. Physicochemical, pasting, and thermal properties, and crystallinity were measured. The texture properties of starch gel (10%, w/w) were examined. Results: The amylose contents of Daeyumi and Sinyulmi starches were 25.57% and 22.59%, respectively. The initial pasting temperature of Daeyumi starch was significantly higher than that of Sinyulmi starch (p<0.05), but other paste viscosities were not different. The peak and conclusion temperatures of Daeyumi starch were higher than those of Sinyulmi starch by differential scanning calorimetry. The shape of Daeyumi starch gel was more clear and rigid than the shape of Sinyulmi starch gel. The surface and the upper side of Daeyumi starch gel were smoother than the surface and the upper side of Sinyulmi starch gel. Hardness and gumminess were higher in Daeyumi starch gel than in Sinyulmi starch gel. The crystallinity types of Daeyumi and Sinyulmi starches were $C_b$ and A types, respectively, but starch gels showed an amorphous type. Conclusion: Therefore, it is suggested that Daeyumi starch would have better physicochemical properties and higher quality of starch gel than Sinyulmi starch.

• Polymer(Korea)
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• v.37 no.5
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• pp.587-591
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• 2013

Poly(3,4-ethylenedioxythiophene) (PEDOT) has good properties such as high conductivity, optical transmittance, and chemical stability, while offering relatively weak physicochemical properties. The main purpose of this paper is the improvement of physicochemical properties such as solvent resistance and pencil hardness of PEDOT. Carboxyl groups in the anionic type waterborne polyurethane (WPU) chains can effectively crosslink each other in the presence of aziridine, resulting in physicochemically robust PEDOT/WPU organic-organic hybrid conductive thin films. The electrical conductivity, optical properties, and physicochemical properties of the hybrid conductive film were compared by varying the solid content and WPU portion in the coating precursor solution. From the results, the transparency and surface resistance of the hybrid film show a decreasing tendency with increasing solid content in the coating precursor. Moreover, solvent resistance and hardness were dramatically enhanced by hybridization of PEDOT and crosslinked WPU due to curing reactions between carboxyl groups.

• International Journal of Oral Biology
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• v.46 no.3
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• pp.105-110
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• 2021

The physicochemical properties of crystalline titanium dioxide nanoparticles (TiO₂ NPs) were investigated by comparing amorphous (amTiO₂), anatase (aTiO₂), metaphase of anatase-rutile (arTiO₂), and rutile (rTiO₂) NPs, which were prepared at various calcination temperatures (100℃, 400℃, 600℃, and 900℃). X-ray diffraction (XRD) and scanning electron microscopy (SEM) analyses confirmed that the phase-transformed TiO₂ had the characteristic features of crystallinity and average size. The surface chemical properties of the crystalline phases were different in the spectral analysis. As anatase transformed to the rutile phase, the band of the hydroxyl group at 3,600-3,100 cm^-1 decreased gradually, as assessed using Fourier transform infrared spectroscopy (FT-IR). For ultraviolet-visible (UV-Vis) spectra, the maximum absorbance of anatase TiO₂ NPs at 309 nm was blue-shifted to 290 nm at the rutile phase with reduced absorbance. Under the electric field of capillary electrophoresis (CE), TiO₂ NPs in anatase migrated and detected as a broaden peak, whereas the rutile NPs did not. In addition, anatase showed the highest photocatalytic activity in an UV-irradiated dye degradation assay in the following order: aTiO₂ > arTiO₂ > rTiO₂. Overall, the phases of TiO₂ NPs showed characteristic physicochemical properties regarding size, surface chemical properties, UV absorbance, CE migration, and photocatalytic activity.

• Korean journal of food and cookery science
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• v.19 no.3
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• pp.271-279
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• 2003

This study was conducted to investigate the sensory and physicochemical properties of beef consomme made with different boiling times (1, 2, 3 and 4hrs). The sensory properties were evaluated with respect to both the acceptability (color, smell, mouth feel, taste, overall acceptability) and intensity characteristics (color, smell, clarify, taste). From the results, the 3hr treatment was most favored for color, smell, mouth feel, taste and overall acceptability, from the sensory evaluation tests. According to a quantitative descriptive analysis of the sensory evaluation for the product, the color, smell and taste gave higher scores with increases in the boiling time. As for the physicochemical characteristics, the pH was increased with increasing boiling time. The reducing sugars, turbidity and viscosity increased with increasing boiling time. The colorimetric lightness values (L) decreased, and redness (a), yellowness(b) and color difference values (ΔE) increased with increasing boiling time. There were 18 free amino acids identified; the alanine, glutamic acid, arginine and leucine contents were high in the free amino acids of the consomme made with different boiling times. There were 3 free sugars identified, glucose, fructose and sucrose. The free sugar contents increased with increasing boiling time. There were changes in the mineral contents of the consomme made with different boiling time; with high K, Na and P contents. The mineral contents increased with increasing, boiling time. The results showed the consomme made by boiling for 3hrs was superior in both its sensory and physicochemical qualities.

• Asian-Australasian Journal of Animal Sciences
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• v.26 no.8
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• pp.1197-1204
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• 2013

This study was carried out to investigate the physicochemical and sensory properties of milk with added powdered peanut sprout extract microcapsules (PPSEM) during the storage at $4^{\circ}C$ for 16 d. The size of PPSEM varies from 3 to $10{\mu}m$ as observed by the scanning electron microscopy (SEM). The pH values of all samples ranged from 6.8 to 6.6 during the storage. Release of resveratrol for 0.5 and 1% PPSEM addition was about $0.89{\mu}l/ml$ and TBARS value found to lower during storage of 16 d. The $a^*$ and $b^*$ color values of high concentrations (1.5, 2.0, 2.5 and 3.0%) of PPSEM-added milk samples were significantly increased during the storage (p<0.05). The sensory test revealed that the overall acceptability of PPSEM (0.5 and 1%) added milk sample were quite similar to that of control. Based on the data, it was concluded that the low concentrations of the microcapsules (0.5 and 1.0%, w/v) could be suitable to produce the microcapsule-supplemented milk without significant adverse effects on the physicochemical and sensory properties of milk.

• Proceedings of the Korean Society of Crop Science Conference
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• 2017.06a
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• pp.269-269
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• 2017

Germination is one of the techniques used to enhance the texture properties and nutritional value of the brown rice (BR). Therefore, germinated BR (GBR) has received significant attention during the last decade. Physicochemical and cooking properties of brown rice were examined before and after germination. Germination raised the cooking properties, such as water absorption, expanded volume and soluble solid of cooked BR (brown rice). The texture, measured using tensipresser, was significantly improved by germination. The hardness of cooked BR was decreased by germination, but the GBR was sticker. In RVA, all viscosity value (peak viscosity, break down, set back, and final viscosity) of germinated rice flour was also reduced while gelatinization temperature did not change. Amylose content and amylopectin chain length distribution of BR starch were slightly changed by germination. Overall results revealed that germination was an effective tool to improve texture and cooking properties of BR.

• Journal of Korean Society on Water Environment
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• v.30 no.1
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• pp.80-86
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• 2014

Unlike to natural organic matters (NOMs), effluent organic matters (EfOMs) are not well understood due to their complexity and heterogeneity. In this study, EfOMs from sewage and industrial wastewater treatment effluents and Suwannee River NOM (SRNOM) were isolated into hydrophobic (HPO), transphilic (TPI) and hydrophilic (HPI) fractions. Specific ultraviolet absorbance (SUVA) and fluorescence excitation emission matrix (FEEM) analyses were used to characterize physicochemical properties. In addition, acute toxicity and oxidative stress to Daphnia magna were evaluated to characterize toxicological properties. EfOMs showed similar properties to microbially derived organic matters having low hydrophobicity, which are totally different from SRNOM having high hydrophobicity. Moreover, acute toxicity and antioxidant enzyme activity in D. magna was largely dependent on fraction types of EfOMs. These findings suggest that EfOMs have different physicochemical and toxicological properties compared with those of NOMs, which needs to be further identified with various sources of EfOMs.

• Bulletin of the Korean Chemical Society
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• v.34 no.4
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• pp.1043-1046
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• 2013

Prediction of physicochemical properties of organic molecules is an important process in chemistry and chemical engineering. The MSEP approach developed in our lab calculates the molecular surface electrostatic potential (ESP) on van der Waals (vdW) surfaces of molecules. This approach includes geometry optimization and frequency calculation using hybrid density functional theory, B3LYP, at the 6-31G(d) basis set to find minima on the potential energy surface, and is known to give satisfactory QSPR results for various properties of organic molecules. However, this MSEP method is not applicable to screen large database because geometry optimization and frequency calculation require considerable computing time. To develop a fast but yet reliable approach, we have re-examined our previous work on organic molecules using two semi-empirical methods, AM1 and PM3. This new approach can be an efficient protocol in designing new molecules with improved properties.