• Preventive Nutrition and Food Science
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• v.15 no.4
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• pp.329-334
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• 2010

Buckwheat flour was incorporated into steamed breads by adding the flour in the range of 0~9% based on the Baker's percentages and the physicochemical properties and consumer acceptance were investigated. After mixing, kneading, proofing, and molding, bread dough was steamed for 15 min using a steam tray and boiling water. The samples were cooled to room temperature for 15 min and packed in airtight bags for further analyses. pH of the steamed bread decreased slightly while titratable acidity increased significantly from 1.02 to 1.37 mL with the incorporation of more buckwheat flour in the formulation (p<0.05). Water activity was not affected by the buckwheat flour level (p>0.05). Moisture content slightly decreased from 43.72 to 42.30% while soluble solids content increased from 0.63 to 0.85 as the buckwheat flour concentration increased. As a result of the addition of buckwheat flour, the specific volume decreased from 3.31 to 2.57 mL/g; on the other hand, the spread ratio ranged from 2.17 to 2.21 without significant differences among them (p>0.05). At the higher level of buckwheat content, lower scores of all color parameters ($L^*$, $a^*$, and $b^*$-values) were observed. Firmness increased significantly with an increase in buckwheat flour content (p<0.05). Consumer acceptance tests indicated that incorporation of up to 3% buckwheat flour in the formulation of steamed breads did not significantly influence the consumers' acceptability in all attributes tested, except for color and elasticity.

• Preventive Nutrition and Food Science
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• v.18 no.4
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• pp.287-291
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• 2013

Physicochemical properties and consumer perception of white pan bread as influenced by the addition of Ecklonia cava powder (ECP) were investigated. Freeze-dried Ecklonia cava were ground, sieved through a laboratory sieve and a fraction with particles less than $250{\mu}m$ was used. Amount of ECP added (0~3%) to the bread was found to affect the bread quality significantly (P<0.05). pH, bread height, and volume of the control was significantly higher than others (P<0.05) and decreased significantly (P<0.05) with the addition of ECP. Moisture content showed no significant differences (P>0.05). There were distinctive color changes with the addition of the powder: $L^*$- and $a^*$-values decreased but $b^*$-value increased significantly (P<0.05). The hardness of bread was found to increase but both cohesiveness and springiness showed a reverse trend with the addition of the powder. Consumer acceptance test indicated that ECP content 1% on wheat flour could be the recommended supplementation level for the consumers without sacrificing sensory quality.

• Journal of the Korean Chemical Society
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• v.60 no.5
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• pp.299-309
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• 2016

In this study, the physicochemical and electrochemical properties of carbon nanomaterials and synthesized nano-carbon/Si composites were studied. The nano-carbon/Si composites were ball-milled to a nano size and coated with pyrolytic carbon using Chemical Vapor Deposition (CVD). They were then finely mixed with respective nano-carbon materials. The physicochemical properties of samples were analyzed using Scanning Electron Microscopy (SEM), Energy Dispersive X-ray Spectroscopy (EDS), Raman spectroscopy, X-ray Diffraction (XRD), X-ray Photoelectron Spectroscopy (XPS), and surface area analyzer. The electrochemical characteristics were investigated using the galvanostatic charge-discharge and cyclic voltammetry (CV) measurements. Three-electrode cells were fabricated using the carbon nanomaterials and nano-carbon/Si composites as anode materials and LiPF₆ and LiClO₄ as electrolytes of Li secondary batteries. Reversibility using LiClO₄ as an electrolyte was superior to that of LiPF₆ as the electrolyte. The initial discharge capacities of nano-carbon/Si composites were increased compared to the initial discharge capacities of nano-carbon materials.

• Korean journal of food and cookery science
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• v.33 no.2
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• pp.190-197
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• 2017

Purpose: The purpose of this paper was to analyze the physicochemical properties related to peeling rate of Korean chestnut. Methods: Analyses were carried out for weight, thickness, polyphenol, amino acid and peeling ratio for Korean chestnut. The correlation between these physicochemical components and peeling ratio of chestnut was measured. Results: The average of thickness for inner shell and outer shell was 0.66 mm and 0.93 mm, respectively. The average peeling ratio was 77.51%. A significant negative correlation was found between peeling ratio and thickness of the inner shell ($r=-0.80^{***}$, p<0.001). Analysis for the polyphenol composition of inner shell by HPLC was carried out and peaks 2 ($r=-0.56^*$, p<0.05), 11 ($r=-0.68^{**}$, p<0.01), 14 ($r=-0.52^*$, p<0.05), 28 ($r=-0.66^{**}$, p<0.01) showed a significant negative correlation with the peeling ratio. Conclusion: Thickness of chestnut inner shell was determined as the most influential factors of peeling.

• Journal of the Korean Professional Engineers Association
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• v.23 no.2
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• pp.29-33
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• 1990

• Korean Journal of Rural Living Science
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• v.4 no.1
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• pp.9-12
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• 1993

• Korean Journal of Food Science and Technology
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• v.51 no.6
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• pp.584-591
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• 2019

Of all the various types of tea that are available, Pu-erh tea has attracted much attention because of its healthpromoting effects. The objective of this study was to investigate the physicochemical and antioxidant properties of two types of Pu-erh tea, Gushu Pu-erh and typical Pu-erh, extracted at 80 and 100℃, respectively. The Gushu Pu-erh extracts showed lower pH but higher antioxidant potential at both the temperatures, as compared to the typical Pu-erh. The mineral content of the tea extracts was greater at 100℃ than at 80℃. Among the seven categories of the flavor compounds that were detected, the peak area of esters was the highest in the Gushu Pu-erh extracts. The type of tea and the extraction temperature significantly affected the physicochemical and functional properties of these tea extracts. This study revealed that Gushu Pu-erh extracted at 100℃ for 3 min with 30 s of shaking provides better results in terms of the antioxidant potential and mineral content.

• Korean Journal of Food Science and Technology
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• v.20 no.6
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• pp.834-839
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• 1988

Physicochemical properties of defatted and 1% palmitic acid reincorporated rice starch were investigated comparing with nondefatted starch. Amylose content of defatted starch was higher than that of nondefatted and reincorporated starch. Transmittance, swelling power and solubility of nondeffated and reincorporated starch exhibited two stage behavior but these behaviors were disappaered by defatting. All starches showed a typical A type in X-ray diffraction but relative crystallinity was decreased by defatting. Also by defatting, peak viscosity and break down of amylogram were disappeared and set back was increased.

• YAKHAK HOEJI
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• v.5 no.1
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• pp.20-23
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• 1960

The study of the isolative determination of the mixed weak bases of INAH and NA-Pas potentimetrically considering the properties of solvents for the INAH and Na-PAS, dielectric constant and solvative properties of solvents are described. The methanol: dioxan (4:1) and glacial acetic acid: dioxan (4:1) are studied first as the mixed solvent, using the N/10 perchloric acid and glacial acetic acid solution as the titrant. The authors found that there is no inflection on INAH with the methanol: dioxan solvent system and on Na-PAS at glacial acetic acid dioxan solvent system. By applying methanol glacial acetic acid dioxan (1:1:1) solvent system, Na-PAS and INAH were successfully determined isolatively from the mixed sample, showing the distinguished inflections respectively as shown in the titration curves in figures 3 and 4. It is found that this method could save considerable time for the isolative determination of the mixed sample of week bases as Na PAS and INHA which were quite difficult to be determined by the present routine at control laboratory.

• Journal of the Korean Society of Food Culture
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• v.23 no.2
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• pp.235-242
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• 2008

In this study, the physicochemical and microbiological properties of market-available skate (Raja kenojei) kimchi were evaluated in comparison to long-term fermented Baechu kimchi. The comparative results for the skate (Raja kenojei) and Baechu kimchi products are as follows: salt concentrations = 3.40% and 3.95%, respectively; pH and acidity values = 4.01 and 3.90, and 0.65% and 0.82%, respectively; redox potential Eh values = 119.82 mV and 123.08 mV respectively; reducing sugars levels = 15.51 mg% and 13.23mg%, respectively; ascorbic acid levels = 24.21mg% and 22.18mg%, respectively; color L-values = 46.86 and 44.54, a-values = 15.46 and 12.28, and b-values = 29.94 and 28.36, respectively; hardness properties = 11.36 kgf and 10.23 kgf, respectively; hot water soluble pectin (HWSP) contents and sodium hexametaphosphate soluble pectin (NaSP) contents = 15.23% and 17.35%, and 32.51% and 29.64%, respectively; hydrochloric acid soluble pectin (HClSP) contents = 55.1% and 53.2%, respectively; total viable cell counts = $4.78{\times}10^8$ and $1.35{\times}10^8$, respectively; lactic acid bacteria counts = $5.18{\times}10^5$ and $1.32{\times}10^5$, respectively; and yeast levels = $8.52{\times}10^5$ and $5.23{\times}10^5$, respectively.