• Journal of Wetlands Research
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• v.20 no.4
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• pp.322-329
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• 2018

In this study the community characteristics of benthic macroinvertebrates distributed in stream of Gaya Mountain were figured out and the correlation with the physicochemical water quality factors were calculated. During the study period, total 4 phyla, 6 classes, 13 orders, 36 families, 100 species of benthic macroinvertebrates were recorded. Ephemeroptera were the most dominant followed by Trichoptera, Plecoptera, Diptera, Non-insecta, Hemiptera, and Odonata. The overall dominant species was Cincticostella levanidovae by dominance rate in 17.72%, subdominant species was Hydatophylax nigrovittatus by dominance rate in 6.15%. The biotic indices showed the diversity index 5.17, richness index 12.44, dominant index 0.24 and evenness index 0.78, there is no absolutely dominant benthic macroinvertebrates in the stream of Gaya Mountain. We identified the correlation between the species number and individuals of main taxa and the physicochemical water quality factors. Ephemeroptera and Plecoptera showed a negative correlation with water temperature, but they represented a positive correlation with the dissolved oxygen. This results suggest that water temperature and dissolved oxygen are important physicochemical water quality factors affects the distribution of Ephemeroptera and Plecoptera, the indicators of clean water stream.

• Agricultural and Biosystems Engineering
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• v.2 no.2
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• pp.59-62
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• 2001

The starch content of apples, which is related to the maturity and ripeness, was quantified by using a computer vision system. The stained area was measured by image analysis when an apple slice was stained with KI/I$_2$ solution. The ratio of stained area of the apple slice to its whole area, so called the starch index, was defined as an indicator of the starch content. When Tsugaru apples were manually sorted into immature, turing and mature groups, their starch indices were 0.374, 0.312 and 0.129, respectively. The starch index had relationships to various physicochemical properties of Tsugaru apples. At the statistically significant level of 0.1%, it was correlated with the pH value, bio-yield force, rupture force and color of intact and skin-removed apples. At the 1% significant level, it had the correlation with the density and moisture content.

• Preventive Nutrition and Food Science
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• v.16 no.4
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• pp.339-347
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• 2011

Flour and isolated starch from chickpea (desi type, 328S-8) were evaluated for their in vitro digestibility and physicochemical properties. The protein content, total starch content and apparent amylose content of chickpea flour and isolated starch were 22.2% and 0.6%, 45.8% and 91.5%, and 11.7% and 35.4%, respectively. Chickpea starch granules had an oval to round shape with a smooth surface. The X-ray diffraction pattern of chickpea starch was of the C-type and relative crystallinity was 24.6%. Chickpea starch had only a single endothermic transition (13.3 J/g) in the DSC thermogram, whereas chickpea flour showed two separate endothermic transitions corresponding to starch gelatinization (5.1 J/g) and disruption of the amylose-lipid complex (0.7 J/g). The chickpea flour had a significantly lower pasting viscosity without breakdown due to low starch content and interference of other components. The chickpea starch exhibited significant high setback in the viscogram. The average branch chain length, proportion of short branch chain (DP 6~12), and long branch chains (DP${\geq}$37) of isolated chickpea starch were 20.1, 20.9% and 9.2%, respectively. The rapidly digestible starch (RDS), slowly digestible starch (SDS) and resistant starch (RS) contents of chickpea flour and starch were 9.9% and 21.5%, 28.7% and 57.7%, and 7.1% and 9.3%, respectively. The expected glycemic index (eGI) of chickpea flour (39.5), based on the hydrolysis index, was substantially lower than that of isolated chickpea starch (69.2).

• Journal of the Korean Society of Food Culture
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• v.36 no.5
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• pp.484-491
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• 2021

This study investigated the effect of dry heat treatment (DHT) on the physicochemical properties of hard type (HR) and floury type (FR) rice to improve the processing aptitude of rice flour. The rice flour was heated at 130℃ for 0, 2 and 4 hours, and the color value, water absorption index (WAI), water soluble index (WSI), swelling power, solubility, pasting properties, particle shape and the X-ray diffraction were measured. After DHT, the L value of rice flour decreased, and the b value increased. The WAI, WSI, swelling power and solubility of HR and FR increased with the increase of treatment time. The cold viscosity and setback increased, while breakdown decreased. Cracks and lumps formed with fine particles were observed. The X-ray diffraction pattern was A-type, while the diffraction intensity decreased. According to the results of the two-way analysis of variance (ANOVA) test, the hydration and pasting properties were significantly different between HR and FR and were affected by DHT time. The results suggest that the properties of modified rice flour by DHT can be used in the food industry.

• Proceedings of the Korean Society for Agricultural Machinery Conference
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• 2000.11b
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• pp.204-209
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• 2000

At harvest, the starch contents of apples, which were related to their maturity, were quantified by using image analysis. The stained area was measured by a computer vision system when an apple slice was stained with KI/I$_2$ solution. The stained area ratio of the stained area of the apple slice to its whole area, or the starch index, was defined as an indicator of starch content. When Tsugaru apples were manually sorted into immature, turning and mature groups, their starch indices were 0.374, 0.312 and 0.129, respectively. Meanwhile, the starch index had correlation to various physicochemical properties of Tsugaru apples. At the statistically significant level of 0.1 %, it was correlated with the pH value, bio-yield force, rupture force and color of intact and skin-removed apples. At the 1 ％ significant level, it had the correlation with the density and moisture content.

• Journal of environmental and Sanitary engineering
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• v.10 no.2
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• pp.36-45
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• 1995

Physicochemical environments and phytoplankton community in the nakdong river middle basin were investigated during a period of 1 year from Nov. 1993 to Oct. 1994. The ranges of Physicochemical environment factors in the nakdong river middle basin were $3.6~27.4{\circ}C$ for temperature, 7.1~9.3 for pH, $7.1~12.7mg/{\ell}$for DO, $0.7~2.1mg/{\ell}$ for BOD, $31~52mg/{\ell}$ for alkalinity, $2.101~3.3mg/{\ell}$ for T-N, $0.052~0.099mg/{\ell}$ for T-p, $5.4~92.3mg/m^{3}$ for chlorophyll-a. The number of Phytoplankton was lowest in Jan. that is, 244ce11s/ml and that was highest in Sep. 1201 cells/ml. The increase of dominant genera were correlated with the total nomber of phytoplanktons. Bacillariaceae, chlorophyceae, cyanophyceae, and euglenophlrceae were to 74.5%, 20%, 3.5%, and 2.2% respectively. Bacillariaceae were abundant during all the year round except for Jun, Jul, Aug. Chlorophyceae were plentiful in Jun, Jul, Aug. Tase-and odor-causing algae and filter clogging algae were 72% in Nov. and 93.5% in Jun. They were abundant all the year round except for winter, so they influenced on the treatment of tap water system. They belong to the general asterionella, cyclotella, melosira, nitzschia of bacillariaceae and actinastrum, pediastrum of chlorophyceae. Dominace index was low in winter and high in umber. Diversity index and equitability index were low in summer and high in winter. Therefore, the structure of phytoplankton community of the nakdong river middle basin was different form season to season.

• Korean journal of food and cookery science
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• v.27 no.1
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• pp.85-99
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• 2011

Grinding is an indispensible step in preparation of espresso coffee. The purpose of this study was to evaluate physicochemical and sensory characteristics of espresso according to the grinding grades of coffee beans. Specifically, physicochemical characteristics according to the grinding grades of coffee beans were tested based on foam index, persistence of foam, total solids, concentration, extraction yield, pH, viscosity, total soluble solid content and density. With regard to sensory characteristics, QDA were carried out by 10 trained panels. Persistence of foam, total solids, concentration, extraction, pH and viscosity in physicochemical test showed significant differences among the three categories of the samples. In other words, the finer the size of particles was, the higher value was, at the p=0.001 value. Meanwhile, the value of foam index and total soluble solid content to the grinding grades was the highest in 'fine', at the p=0.001 value. Tiger-skin effect in crema, an important attribute for excellent espresso coffee, was perceived by all of the panels in 'fine'. Also, intensity of flavor was perceived as to the strongest in 'fine'. Moreover, 'fine' had the sweetness to balance the acids and bitters. In conclusion, according to the grinding grades, it was identified that there were differences in the physicochemical and sensory characteristics. Furthermore, when the size of particles was 'fine', it brought to the most positive result.

• The Korean Journal of Food And Nutrition
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• v.23 no.3
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• pp.419-427
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• 2010

The focus of the current study was to investigate the physicochemical properties of a corn starch-sponge matrix prepared at a low concentration below gel forming by freeze-drying. The effect of variables(starch concentration, heating temperature, and heating hold time) on the physicochemical properties of the samples was analyzed by response-surface methodology. Regression models on the properties of samples such as hardness, springiness, and water solubility index(WSI) showed high correlation coefficients(r>0.95) and significant F values, but regression models for the other properties(swelling power, apparent viscosity, reducing sugar content, and digestibility) showed them to have relatively low significance. Sample hardness of sample showed the highest value at condition of $90^{\circ}C$ and 5%, whereas springiness was at a maximum at $130^{\circ}C$ and 5%. Also, at 1% of starch concentration, mechanical properties were greatly decreased as the relative humidity increased, compared with the 3% and 5%, especially in the hardness of samples. The WSI showed an increasing trend with heating temperature regardless of starch concentration. Overall, the physicochemical properties of freeze-dried corn starch-sponge matrix were influenced much more by starch concentration and heating temperature than by heating hold time. The results of this study show that the basic properties of freeze-dried corn starch-sponge matrix can be used for the specific food applications or as a functional material for its stability.

• Food Science of Animal Resources
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• v.38 no.6
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• pp.1273-1285
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• 2018

The aim of this study is to determine the some physicochemical (proximate composition, pH and $a_w$ values) and reconstitution (wettability, dispersibility and solubility index (SI)) properties of spray-dried bone broth powder (BBP) along with the effects of the addition of different carrier agents. Subsequently, the powdered products were stored to determine the storage stability (pH, lipid oxidation, color, browning index) for 3 mon at $-18^{\circ}C$. For this purpose, firstly marrow-containing bones (Os femur and Os humerus) have been boiled to get the bone broth. Three different emulsions were respectively prepared (1) 20% maltodextrin (MD) added BBP, (2) 20% whey powder isolate (WPI) added BBP and (3) 10% MD and 10% WPI added BBP and the emulsions were dried using a spray-dryer with $185^{\circ}C$ inlet and $95^{\circ}C$ outlet temperature. The proximate composition and reconstitution properties of BBP were found statistically different (p<0.05) depending on the use of different carrier agents. MD added BBP showed uniform and smooth morphology. The color, browning index, thiobarbituric acid reactive substances (TBARS) and pH values of BBP significantly changed (p<0.05) during storage. In conclusion, both the results of physicochemical and storage period analyses showed that the most suitable encapsulation material in the production of the bone broth powder is MD.

• Food Science and Biotechnology
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• v.17 no.2
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• pp.234-240
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• 2008

The optimal conditions for the production of branched dextrin from com starch (CSBD) using branching enzyme (BE) were established by investigating the degree of retrogradation of the gelatinized starch. The physicochemical properties of CSBD prepared using the established process were evaluated. It was found that physicochemical properties of com starch were greatly modified by BE treatment. CSBD had a higher dextrose-equivalent value and water solubility than the corresponding control. On the other hand, the viscosities in gelatinized solution and amylose contents of CSBD were lower than those of the control. A high-performance size-exclusion chromatography/multiangle laser light scattering/retractive index (HPSEC/MALLS/RI) system showed that the average molecular weight of CSBD was lower than that of the control. The pasting viscosities of CSBD were stable during the entire temperature cycle. In general, the BE treatment resulted in the retrogradation during storage being lower for CSBD than for the control.