• Korean Journal of Food Science and Technology
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• v.34 no.4
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• pp.583-589
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• 2002

The rheological properties of apple pectins and tomato pectins with different degrees of side branches (sample I and sample II) were investigated with wide range of shear rate by theological modeling. Among the Power law model, Cross model and Carreau model, the Carreau model was the best fitted to the experimental data. Increasing in branching of apple pectins resulted in higher zero-shear viscosity $({\eta}_0)$. But, tomato pectins that have a low degree of side branches were shown litte difference between sample I and sample II. It is concluded that side branches of pectins can result in significant difference in rheological properties. And, this is predicted by the Carreau model.

• Food Engineering Progress
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• v.21 no.4
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• pp.341-350
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• 2017

The relationship of in vitro starch digestibility and gel strength was investigated at various concentrations (10-30%) of rice cultivars with different amylose contents (27.9, 17.9, and 5.2%). As the rice flour concentration increased, predicted glycemic index decreased, but gel strength increased regardless of amylose contents. Gel strength correlated strongly with amylose content, whereas in vitro starch digestibility was more highly affected by rice flour concentration than by amylose contents. Moreover, the impact of degree of gelatinization on in vitro starch digestibility of high amylose rice was also examined in terms of structural features and rheological properties. The digestion rate of fully gelatinized flour was 1.7 times higher than that of native flour, while the disrupted structure with a different gelatinization degree during starch digestion was visually demonstrated through the X-ray diffraction and molecular distribution analysis. The rice flour changed from an A-type to a V-type pattern and showed difference in crystalline melting. The low molecular weight distribution increased with increasing degree of gelatinization during starch digestion. The apparent viscosity also increased with degree of gelatinization. These results demonstrated that the starch digestibility of rice was more affected by concentration than by amylose content, as well as by the degree of gelatinization due to structural difference.

• International Journal of Internet, Broadcasting and Communication
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• v.13 no.1
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• pp.152-160
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• 2021

The purpose of this study was to investigate the difference in the number of repetitions and the change in electromyographic response during the maximum speed squat exercise according to the depth conditions and the maximum speed squat exercise according to the time of each depth. Ten men in their 20s were selected as subjects and the maximum speed squat was performed for one minute in three environmental conditions (ground, knee depth, waist depth). We found that the number of repetitions according to the depth of water showed a significant difference, and as a result of the post-mortem comparison, the number of repetitions was higher in the ground condition and the knee depth than in the waist depth. And the muscle activity of rectus abdominis, erector spinae, rectus femoris, biceps femoris was increased during ground squat exercise, activity of all muscle was decreased during knee depth squat exercise, and activity of rectus abdominis, erector spinae, biceps femoris, tibialis anterior, gastrocnemius was decreased during waist depth squat. In conclusion, muscle activity of lower extremities during squat exercise in underwater environment can be lowered as the depth of water is deep due to buoyancy, but muscle activity of trunk muscles can be increased rather due to the effect of viscosity and drag.

• Proceedings of the Korean Nutrition Society Conference
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• 1999.05b
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• pp.60-61
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• 1999

The present study examined optimal level of mulberry leave powder, and the method of bread-making were proposed to utilize mulbery leave powder by investigating rhelogical properties of dough and sensory evaluation of bread. The difference of amino acids compositions in flour brew were also investigated by fermentation of S. cerevisiae or bifidobacteria. As the % of mulberry leave powder increases absorption rate of dough was steadily increased, but stability and R!E ratio if dough were dramatically decreased more than 1% leave respectively. R!E ratio value, which indicates gas retnetion property of dough, was not obtained at the level 5%. Gelatinization temperature and maximum viscosity temperature showed a tentency of decrease, resulting in easier cooking of dough. The delay of temperature cauesd by addition of mulberry leave powder was overcome by two step bread making, that is, modified straight dough method adding flour brew fermented 16hrs by bifidobacteria. The firmness of bread was progressively dreased as the amount of mulbery leave powder increased. The addition of 2% level of mulberry powder to bread showed no significant difference comparing with control in sensery evaluation. Amino acids compositions of Flour brew fermented by bifidobacteria was superior th that by S. cerevisae nutritionally.onally.

• Journal of Biosystems Engineering
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• v.37 no.5
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• pp.296-301
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• 2012

Purpose: Combustion and fuel qualities of the animal-fats biodiesel as a heating fuel for agricultural hot air heater were studied. Methods: Biodiesel (BD) was made from animal-fats by reacting with methanol and potassium hydroxide in the laboratory. The biodiesel made in the laboratory was tested for fuel and combustion qualities. Results: The kinematic viscosity and the calorific values of the biodiesels were measured. Kerosene based biodiesel, BD20 (K) showed 18 cSt at $-20^{\circ}C$. It seemed that BD100 was not suitable for a heating fuel under some temperature. As BD content increased, the calorific value decreased up to 40,000 J/g for BD100, while the calorific value of light oil was 45,567 J/g showing difference of 5,567 J/g, about 12% difference. Several different fuels including BD20 (biodiesel 20% + light oil 80%), BD50 (biodiesel 50% + light oil 50%), BD100 (biodiesel 100%), and light oil were tested for fuel combustion qualities for agricultural hot air heater, and their combustion performances were compared and analyzed. Flame dimensions of biodiesels and light oils were almost the same shape at the same combustion condition. Generally, the $CO_2$ amounts of BDs were greater than light oil. However, in this study the differences were minor, so there was no significant difference existed between the BDs combustion and light oil. Conclusions: It seemed that quality was good for heating oil for agricultural hot air heater because of showing no barriers for continuous combustion and proper exhaust gas temperature and $CO_2$ amount discharged. But, for fuel fluidity for higher BD content fuel could be a detrimental problem in situations where the outdoor temperature is lowered. As BD content increased, calorific value decreased up to 40,000 J/g for BD100. Calorific value difference between BD20 and light oil was about 1,360 J/g.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.38 no.1
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• pp.72-84
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• 1993

This study was carried out to understand the varietal variation in physicochemical properties of rice grain and those environmental changes by different transplanting time, and to elucidate the interrelationships among the factors related with eating quality of cooked rice. Fifty three rice samples, among which fifty samples were harvested at ordinary or late transplanted plots of the Crop Experiment Station in Suwon and three samples were harvested orpurchased from Niigata prefecture in Japan, were tested for various physicochemical components of rice grain and some physical factors of cooked rice. All of twenty seven rice cultivars tested were the recent-bred Korean japonica rice showing the wide range of maturity from early to medium-late heading and considerable difference in palatability of cooked rice. Amylose content, taste value by Nireco palatability tester (TVN), iodine blue color of cooking extracts(IB), and the ratio of IB /extracted solid amounts (ES) increased significantly by late transplanting, while viscosity (VN) and Mg / K. N value by Nireco tester, hot-water absorption of milled rice (HA), loss tangent of cooked rice by Rheolograph-Micro(LT), and most viscogram characteristics except setback viscosity (C-P) decreased drastically by late transplanting as compared with ordinary transplanting. Most of physicochemical properties of milled rice revealed narrower varietal variation in lately transplanted plot than in ordinary transplanted one. Protein content (PRO), volume expansion rate of cooked rice(VE), C-P and all physical factors of cooked rice by Rheolograph-Micro showed almost negligible seasonal variation, while amylose content (AM), VN, HA, IB/ES, peak viscosity(P), hot viscosity(H) and breakdown(P-H) viscosity exhibited considerably large seasonal variation. The early-headed varieties revealed lower amylose content and smaller seasonal variation of IB/ES compared with medium or medium-late headed rice varieties. AM was closely associatied with IB and IB / ES and VN was highly correlated with Mg/K. N and TVN in both ordinary and late transplanted plots. VN also was highly negatively correlated with cooking characteristics and highly positively correlated with viscogram properties in ordinary culture. PRO was closely connected with moisture content of milled rice and L T in ordinary transplanted plot. IB, which was closely connected with ES, was also singificantly associated LT, P and P-H in ordinary seasonal culture. IB/ES was highly negatively correlated with P, P-Hand P-H / C-P in ordinary culture but with LT and dynamic viscosity of cooked rice in late seasonal culture. The thirty rice cultivars were largely classified into two varietal groups by cluster analysis with physicochemical properties related with eating quality of cooked rice. Korean and Japanese high-quality rice cultivars were separately distributed in two respective varietal group.

• Textile Coloration and Finishing
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• v.23 no.4
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• pp.263-273
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• 2011

Digital textile printing(DTP) technology made considerable advances in recent years. In this study, a pre-treatment agent has been prepared for the better coloration of digital textile printing. The ink formulation contained three kinds of 5g thickener (CMC, Sodium alginate, Dextrin), 25g urea, 5g sodium carbonate, and 465g distilled water. The optimal sharpness of outline was found in the 1-3% concentration of the pre-treating agent with a viscosity of 10-15 cSt. Even if the color difference between untreated and treated samples was not apparent in the printing step, the color appearance increased after steaming. The color appearance of cyan, magenta, yellow, black reactive colorants increased in the order of CMC>Sodium alginate>Dextrin. Wash fastness to shade change and staining for the treated samples were 4-5 rating, while untreated sample was 1-2 rating. Also, the pre-treated sample with 1:1 mixtures had 4-5 rating. Both dry and wet rubbing fastness to shade change and staining were excellent in the treated samples, whereas rubbing fastness of untreated sample was 1-2 rating. With exception of 3 rating to black color, light fastness properties were 4 rating for the remaining three colors in the regardless of treatment condition and mixing of pre-treating agents. Dry cleaning fastness of all samples were also 4-5 rating irrespective of treatment condition and mixing of pre-treating agents.

• Journal of the East Asian Society of Dietary Life
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• v.23 no.1
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• pp.69-77
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• 2013

Jujube is a functional food, containing medicinal ingredients without side effects. Jujube can relieve digestive upset, inhibit tumor growth and protect the liver. It includes sterols, alkaloids, saponins, vitamins, organic acids, and amino acids. Jujube has also received attention as an anticancer agent and as a diet food. However, it is rare to find yogurt made with jujube, so we considered adding jujube powder to yogurt to popularize it as a new health food. We made yogurt with jujube powder at 0, 1, 2, 3, and 4%. We measured pH, acidity, color properties (brightness, redness, yellowness), viscosity, sensory qualities (color, flavor, taste, overall quality). We also experimented with storage stability at intervals of 1, 5, 10, 15, and 20 days. The results showed that pH increased significantly (p<0.001) with increasing amounts of added jujube powder. The pH also rose significantly with longer storage, but tended to decrease after 20 days. Acidity was reduced during the storage period. Viscosity was highest with 1% added jujube powder (p<0.001) on day 5 of storage (p<0.001). The L color value decreased as the amount of added jujube powder increased, whereas the a-value (redness) and b-value (yellowness) increased (p<0.001). In an sensory test, color in samples with 0, 1, and 2% jujube powder exhibited the highest values (p<0.01), but no significant differences in flavor or texture were observed. Sweetness and sourness were highest in the yogurt with 3% jujube powder (p<0.05). Overall quality tended to be higher for yogurt with 3% jujube powder, but the difference was in significant. Taken together, our results indicate that yogurt with 3% jujube powder may the most suitable for manufacturing purposes.

• Journal of the Korean Society of Food Science and Nutrition
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• v.34 no.1
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• pp.87-92
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• 2005

This study was investigated to examine gelatinization properties of waxy black rice starches. X-ray diffraction patterns in raw starches showed traditional A type of cereals. The crystalline regions of both black rice and Shinsunchalbyeo starches disappeared when temperature increased to $65^{\circ}C$ where the crystalline regions of two starches changed to amorphous ones. Scanning Electron Microscope showed that granule type of Shinsunchalbyeo starch was more collapsed compared to that of black rice starch heated at 6$0^{\circ}C$. Gelatinization in both samples completed when samples were heated at 63$^{\circ}C$. The results by Differential Scanning Calorimetry (DSC) revealed that gelatinization patterns were similar in both samples. In Rapid Visco Analyzer examination, there was no difference in peak viscosity, breakdown, final viscosity and setback between Shinsunchalbyeo and waxy black rice starches.

• The Korean Journal of Food And Nutrition
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• v.25 no.4
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• pp.762-769
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• 2012

In order to study the cooking characteristics of four rice cultivars of Seolhyangchal, Baegjinju, Ilpum and Haiami, we investigated the relationship between the textures of cooked rice and their physicochemical properties. Different levels in grain weight. length/width ratio and amylose content were observed among the four rice cultivars. There was no significant difference in the amylopectin chain length distribution among the cultivars. Water absorptions of rice grains during soaking were completed between 30 and 40 min, with Haiami showing the slowest absorption. Significant differences in the viscosity properties of rice flour were found by a Rapid Visco Analyser. Baegjinju with low amylose content had the highest viscosity in paste breakdown. According to the DSC results of rice starches, there were significant differences in the onset, peak and conclusion temperatures of the endothermic peak. Gelatinization enthalpy showed energy content changes between 4.20 and 6.97 J/g, with the lowest change in Haiami. Texture properties of cooked rice were assessed using a Texture Analyzer, which showed that the hardness of cooked rice was decreased with soaking than without soaking. However, this finding was not applicable for Haiami rice.