• Fisheries and Aquatic Sciences
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• v.17 no.3
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• pp.299-304
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• 2014

The objective of this study was to elucidate the physicochemical characteristics of gelatin extracted from jellyfish Rhopilema hispidum. We investigated the proximate composition, amino acids, gel strength, gelling/melting points, dynamic viscoelastic properties, and viscosity of jellyfish gelatin. Jellyfish gelatin contained 12.2% moisture, 1.5% lipid, 2.1% ash, and 84.8% protein. Glycine, hydroxyproline, proline, and alanine were the predominant amino acids. The gelatin showed a gel strength of 31.2 kPa, a gelling point of $18.0^{\circ}C$, and melting point of $22.3^{\circ}C$. The gelatin was composed of ${\alpha}_1$-chain, ${\alpha}_2$-chain, ${\beta}$-chain, and ${\gamma}$-chain. During cooling and heating process, jellyfish gelatin showed lower elastic modulus (G') and loss modulus (G") values than mammalian gelatin. Jellyfish gelatin did not show superior rheological properties to mammalian gelatin, like other fish gelatin; however, it can be used in various food and cosmetic products not requiring high gel strength.

• Journal of Applied Biological Chemistry
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• v.50 no.4
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• pp.234-238
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• 2007

The effects of ultra-fine pulverization on the physicochemical properties of rice starch (RS) were investigated using a high impact planetary mill. After pulverization, RVA characteristics, peak viscosity, break down, and set back values of RS decreased from 274.75 to 9.42 RVU, 214.46 to 6.17 RVU, and 87.80 to 17.00 RVU, respectively. The pasting properties also changed significantly. X-Ray diffractogram revealed RS had four A-type peaks, which disappeared after pulverization. The peak temperature and gelatinization enthalpy of RS using differential scanning calorimetry (DSC) were 13.99 J/g at $75.14^{\circ}C$, whereas the pulverized RS (PRS) had two peaks, 0.13 J/g at $63.88^{\circ}C$ and 1.23 J/g at $101.24^{\circ}C$. DSC measurement showed the retrogradation degree of PRS was lower than that of RS after storage at 4 and $25^{\circ}C$. The enzymatic (${\alpha}$-amylase) digestibilities of RS and PRS were 72.7 and 77.3%, respectively.

• Journal of the Korean Society of Food Culture
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• v.19 no.5
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• pp.491-498
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• 2004

In order to study the quarantine and sanitization methods for dried red pepper, comparative effects of commercial fumigation (methyl bromide/MeBr, $phosphine gas/PH_{3}$ and gamma irradiation (5, 10 kGy) were investigated in terms of its physicochemical properties. There were no noticeable chances in pH and soluble solids among the untreated control, irradiated and fumigated samples soon after treatments, but some decrease was found in stored samples (especially soluble solid in fumigated samples) for 8 months under room temperature. Total sugar content was influenced by storage time rather than both treatments. Immediately after treatments, reducing sugar content was significantly reduced in the samples including pericarp when exposed to fumigants (p<0.05), while an apparent decrease was observed in the stored samples including seeds with negligible differences among treatment groups. The electron donating ability (EDA) of the extracts was high in the order of pericarp, whole pepper, powdered pepper and seeds, which was reduced during storage for 8 months particularly in the samples containing seeds. The EDA of irradiated samples during storage was equal to that of the control sample, whereas that of fumigated samples was relatively low (p<0.05).

• Journal of Ginseng Research
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• v.9 no.2
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• pp.270-284
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• 1985

In order to investigate the change of physicochemical properties of ginseng root starch during storage and heat treatment, the roots were stored for 15 days at 5 $^{\circ}C$, 15 $^{\circ}C$, 3$0^{\circ}C$ and 45$^{\circ}C$, and heated for 15 hours at 6$0^{\circ}C$, 7$0^{\circ}C$, 8$0^{\circ}C$, 9$0^{\circ}C$, respectively. The starch content was decreased from about 40% to 23-26% and sucrose content was increased from 4% to 12-16% during storage for 15 days at 5-45$^{\circ}C$. Maltose, which was not detected in fresh samples, was increased up to 8.5% during storage or heat treatment. Granular size of the starch was decreased and some of the granules were broken during storage. Amylose content in the starch was decreased from 33% to 20%, and blue value and alkali number of the starch were increased slightly, and solubility and swelling power of the starch were decreased during storage. 3 The higher storage temperature and the longer storage time, the starch was more susceptible to gelatinize, and the viscosity of the starch was lowered with the susceptibility of gelatinization. The susceptibility of degradation of the starch by the amylase was increased and amylolytic activities in ginseng root were, also, increased during storage.

• Journal of the East Asian Society of Dietary Life
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• v.7 no.3
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• pp.315-324
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• 1997

Physicochemical properties of potato starches oxidized with sodium hypochlorite containing 1.5, 3.0, 4.5, and 6.0% active Cl/g starch at pH 7.0 were examined. Carboxyl group contents of oxidized potato starches were proportional to active chlorine concentration in use and water binding capacity, alkali number, and solubility increased with increasing the degree of oxidation. Blue value and iodine binding property indicated the change of amylose structure by the oxidation. Gelatinization trends obtained from transmittance and DSC thermograms showed that gelatinization temperature was lower as starch was oxidized higher. X-ray diffraction patterns and scanning electron micrographs implied oxidation might occur on the surface amorphous regions of starch granule.

• Food Science and Preservation
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• v.5 no.4
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• pp.368-373
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• 1998

The effects of steeping and washing were investigated in the physicochemical properties of acorn flour. The contents of crude protein, ash and total phenol of acm flour were gradually decreased with the steeping days and washing times. However, the contents of crude fat and dietary fiber were little different. The more steeping days and/or washing times became large, the more the color of acorn flour became light. Swelling power was enhanced by increasing of steeping days and washing times but solubility was some decreased Water binding capacity was decreased and intrinsic viscosity was increased with the increased steeping days and washing times. Washing times were more influential than steeping days to those changes.

• Journal of the East Asian Society of Dietary Life
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• v.5 no.3
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• pp.255-262
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• 1995

Studies were carried out to investigate physicochemical properties of taro during the pretreatment process of making Toranbyung. Seventeen kinds of amino acids were found in taro. Aspartic acid and glutamic acid were most plentiful among those amino acids. Essential amino acids were about 42.7% of the total amino acids. Sulfur containing amino acids, mehtionine and cystine were about 2.7% The amylograph indicated that the initial temperature triggering gelatinization of both rice flour mixed with taro and glutinous rice flour mixed with taro increased as the amount of taro increased. But the maximum viscosity of rice flour mixed with taro did not increase as the amount of taroincreased while the maximum viscosity of glutinous rice flour mixed with taro increased as the amount of taro increased. And the peak temperature of both rice flour mixed with taro and glutinous rice flour miced with taro increased as the amount of taro increased. The alkali degree of insoluble ash was higher than that of soluble ash. Glutinous rice dough had more total sugar than rice dough. Yellowness of rice dough was higher than that of glutinous rice dough.

• Journal of the Korean Chemical Society
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• v.64 no.5
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• pp.259-266
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• 2020

The main purpose of this study is to examine the different physicochemical properties of spray-dried products. The carrier agents and powders after the spray-drying process were analyzed for encapsulation yield, moisture content, color parameters, total polyphenol content (TPC), antioxidant capacity (AC), bulk density, flowability, wettability, hygroscopicity, water solubility index (WSI), particle size and microstructure. The spray-drying process was carried out with different carrier agents including maltodextrin (MD) and the combination of maltodextrin and gum arabic (MD-GA) with MA/GA ratio of 70/30, dried at the inlet/outlet air temperature of 160 ℃/70 ℃, 4 bar, airflow rate of 70 ㎥·h^-1 and feed flow rate of 750 mL·h^-1. The results showed that the different carrier agents have significant influences on the physicochemical properties of the powder produced by the spray-drying method. In there, while the values of recovery efficiency and flowability of spray-dried products from MD are higher than those of spray-dried products from MD-GA combination, the opposite is true for the values of TPC, AC, bulk density and wettability, whereas hygroscopicity and WSI values are equally represented in both products.

• Journal of Soil and Groundwater Environment
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• v.16 no.1
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• pp.51-61
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• 2011

Germination tests were conducted to determine the practical concentration levels at which plants can reproduce naturally during the phytoremediation of soils contaminated with a high concentration of petroleum hydrocarbons and heavy metals. The effects of humic acids on plant growth and soil physicochemical properties were also investigated. The results show that phytoremediation can be applied in soils contaminated by multiple contaminants at the former soil contamination potential level of Korean soil quality standards considering successful natural reproduction. It was observed that germination rates of Helianthus annuus and Festuca arundinacea were high after all treatments, and transplantation was more appropriate for Phragmites communis in phytoremediation. Humic acids had a positive effect on the growth of both aboveground and belowground biomass of herbaceous plants. Growth inhibition by multiple contaminants is more severe in the case of aboveground biomass. Germination and growth tests suggest that Helianthus annuus is a suitable phytoremediation plant for soils contaminated with a high concentration of petroleum hydrocarbons and heavy metals. The addition of humic acids also caused changes in the physicochemical properties of contaminated soils. An increase in the carbon and nitrogen content due to the addition of humic acids and a correlation between cation exchange capacity(CEC) and the organic matter content were observed.

• Food Science and Biotechnology
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• v.15 no.3
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• pp.374-379
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• 2006

This study was carried out to investigate the physicochemical properties of frozen pork muscle which has been thawed using the ohmic thawing process, and to establish the optimal ohmic power intensity. The samples were frozen at $-40^{\circ}C$ and thawed at 0, 10, 20, 30, and 40 V by ohmic thawing. Increasing ohmic power intensity correlated with increased thawing rates. The relationship between ohmic power intensity and thawing rate can be represented as a polynomial function. The pH value decreased with increasing ohmic power intensity (p<0.05). With regard to color measurement, the $L^*$, a, and b values of thawing at all ohmic power intensities were not significantly different. The water holding capacity showed a peak value of 41.62% with an ohmic thawing intensity of 30 V. Cooking losses were lowest at the lowest ohmic thawing intensity of 10 V. Thiobarbituric acid reactive substance (TBARS) levels with all thawing processes were slightly higher than that of the control (p<0.05). Increasing ohmic power intensity did not tend to change the total volatile basic nitrogen (TVBN) value.