• Applied Biological Chemistry
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• v.27 no.2
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• pp.79-85
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• 1984

The physicochemical properties of starch isolated from two kinds of waxy barley were investigated. The average diameters of starch granules of Changyoung and Smire were 13.6 and 16.6 microns, respectively, and most of starch granules were round shape. X-ray diffraction patterns of two samples were A-types and amylose contents of two waxy barley starches were 4%, blue values and alkali numbers of Changyoung and Smire were 0.22 and 0.18, 5.2 and 4.0, raising powers of them were 167 and 173, respectively. The optical transmitance of 0.1% suspension of waxy barley starches increased rapidly from $51^{\circ}C\;to\;75^{\circ}C$. Amylogram data on 5% of Changyoung and Smire starch solutions showed the gelatinization temperature of 63 and $62^{\circ}C$, maximum peak hight of 920 and 900 B.U., respectively. Waxy barley starches had higher swelling powers than non waxy barley starch. The starch pastes prepared from waxy barleys retrograded much slower than that of non waxy barley.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.51 no.spc1
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• pp.21-24
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• 2006

We analyzed factors which related with rice quality at seven varieties. The whiteness of Daeyabyeo, Hopyeongbyeo and Koshihikari were higher than those of other rice varieties. In the hardness of brown rice, Ilpumbyeo was the lowest, and Sindongjinbyeo was the highest among varieties. The hardness cooked rice of Hopyeongbyeo were significantly low, and cohesiveness of those were significantly high. but adhesiveness, viscosity and gumminess of Ko-shihikari was high than other cooked rice varieties. The palatability of Daeyabyeo and Hopyeongbyeo were higher than those of Ilpunbyeo and Ungwangbyeo. Varieties which were known as having good palatability were higher in the breakdown, while setback and consistency were low. In those varieties, factors of upper were correlated with palatability, so this were supposed to determine palatability.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.59 no.2
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• pp.174-180
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• 2014

This study was conducted to know the effect of low radiation during grain filling stage of rice on its grain yield, components, physicochemical properties and palatability, compared to the effect of natural light. Ripened grain ratio, 1000 grain weight of brown rice, milled rice yield of Mipum, Hopum, and Sindongjin were reduced as the shading treatments become higher. After harvest, physicochemical properties of rice influencing eating quality were investigated. Protein content of milled rice was increased, but palatability was decreased by shading treatments. Change of milled rice proteins and palatability due to shading treatments were found to be less in Mipum than that in Hopum and Sindongjin. With regard to amylogram properties, shading treatments resulted in a significant decrease in peak trough final breakdown viscosities of rice flour, though it increased pasting temperature and setback viscosity. The degree of the 55% shading effect was more intensive than the 35% shading effect in changes of ripened grain ratio, 1000 grain weight of brown rice, milled rice yield and milled rice protein.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.44 no.4
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• pp.355-363
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• 1999

The experiments were carried out to elucidate the varietal variation of retrogradation in aged cooked rice and its association with some physicochemical properties of milled rice. The fifteen rice materials were selected from forty-three low-amylose japonica and Tongil-type rice cultivars based on palatability and retrogradation of cooked rice stratified by preliminary sensory evaluation of warm and cooled cooked rice. One japonica glutinous rice variety was included for comparison of retrogradation of cooked rice. The $\alpha$-amylase-iodine method was adopted for checking the varietal difference in retrogradation of cooked rice. The desirable checking time for evaluating the varietal difference in deterioration of aged cooked rice was four hours after storing in room temperature and two hours after preserving in refrigerator based on the largest coefficients of variations in degree of retrogradation of cooked rice. The rice cultivars revealing the relatively slow retrogradation in aged cooked rice were Ilpumbyeo, Chucheongbyeo, Sasanishiki, Jinbubyeo and Koshihikari. A Tongil-type rice, Taebaegbyeo, and a japonica cultivar, Seomjinbyeo, showed the relatively fast deterioration of cooked rice. The retrogadation index represented by the percentage of retrogradation difference between warm and cooled cooked rice to original estimates of warm cooked rice was significantly affected by the degree of retrogradation of cooled cooked rice. Generally, the better rice cultivars in eating quality of cooked rice showed less retrogradation and much sponginess in cooled cooked rice. Also, the rice varieties exhibiting less retrogradation in cooled cooked rice revealed higher hot viscosity and lower cool viscosity of rice flour in amylogram. The sponginess of cooled cooked rice was closely associated with magnesium content and volume expansion of cooked rice. The hardness-changed ratio of cooked rice by cooling was negatively correlated with solids amount extracted during boiling and volume expansion of cooked rice. The major physicochemical properties of rice grain closely related to the palatability of cooked rice may be directly or indirectly associated with the retrogradation characteristics of cooked nce. The varietal difference in retrogradation of cooked rice can be effectively classified by scatter diagram on the plane of upper two principal components based on some retrogradation properties of cooked rice. The deteriorated structural change in cooled cooked rice by observing through the scanning electron microscope was more conspicuous in the fastly retrograded cooked rice than in the slower one.

• The Korean Journal of Food And Nutrition
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• v.31 no.5
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• pp.653-667
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• 2018

This study evaluated the quality characteristics, the presence of polyphenolic compounds, and radical scavenging activity of rice cooked along with various mixed grains (barley, black soybean, adzuki beans, foxtail millet, proso millet, sorghum, glutinous rice) by following two different cooking methods (normal and pressure cooker). The amylogram and water characteristics of mixed grains showed significant differences based on the presence of different types of mixed grains. The chromaticity, palatability characteristics, presence of phenol compounds, and radical scavenging activity of rice cooked along with different mixed grains showed significant differences according to the nature of mixed grains. Total polyphenol contents of before cooking, cooked-rice added to mixed grains cooked in the normal cooker and a pressure cooker were 4.46~5.16, 0.58~0.93 and 0.65~0.96 mg GAE/g, and total flavonoid contents were 250.74~548.89, 129.26~207.04 and $127.41{\sim}218.15{\mu}g\;CE/g$, respectively. The DPPH radical scavenging activity of before cooking, cooked-rice added to mixed grains cooked in the normal cooker and a pressure cooker was 79.25~181.61, 22.07~53.64 and 7.51~39.97 mg TE/100 g, and ABTS radical scavenging activity was 203.25~328.24, 47.28~84.94 and 58.27~99.51 mg TE/100 g, respectively. Accordingly, it is necessary to different combinations of mixed grains according to the cooking method at home and grain industry.

• Korean Journal of Food Science and Technology
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• v.25 no.6
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• pp.710-715
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• 1993

Physicochemical properties of defatted and lipid-reintroduced kidney bean, mung bean, and corn starches were investigated. Granule shapes of kidney bean and mung bean starches were oval/round, but corn starch was polygonal and each shape was not changed after defatting and lipid reintroducing. The granule sizes of starches ranged $12{\sim}45{\mu}m,\;10{\sim}32{\mu}m\;and\;5{\sim}20{\mu}m$ respectively, but those of lipid reintroduced starches increased slightly. All starches showed Ca type in x-ray diffraction but relative crystallinity was decreased by defatting. The amylose contents of starches increased after defatting but decreased after lipid-reintroduction. The swelling power and solubility of untreated starches at each temperature increased by defatting but decreased by lipid-reintroduction except corn starches. The initial pasting temperatures of kidney bean, mung bean and corn starches by amylograph were $87,\;67\;and\;80^{\circ}C$ respectively, and those of them were lowered by defatting. The peak viscosity, height at $50^{\circ}C$, consistency and setback on amylogram of starches decreased by defatting but increased by lipid-reintroduction.

• Korean Journal of Food Science and Technology
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• v.31 no.4
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• pp.994-998
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• 1999

To evaluate the effects of sucrose-fatty acid ester (SE) on bread-making characteristics, the dough mixing, gelatinization, baking properties with the addition of SE alone and together with other surfactants were investigated. SE increased the peak time and the peak height in mixogram, indicating that it contributed the elasticity of dough. In farinogram, SE increased the peak time and mechanical tolerance index, but reduced the dough stability. SE increased the peak viscosity and reduced the gelatinization temperature and maximum consistency temperature in amylogram. SE increased the specific volume of bread loaf and retarded the increase in hardness of bread during storage, showing its anti-staling effects. The maximum anti-staling effect of SE was observed at 0.5% level. The addition of SE (0.2%), SSL (0.15%) and ES-95 (0.15%) blend showed the maximum specific loaf volume, and that of SE (0.25%) and SSL (0.25%) did the maximum anti-staling effect.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.35 no.2
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• pp.137-145
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• 1990

Six commercial rice varieties were cultivated at different locations in 1987 and 1988. Rice samples harvested from 8 to 20 locations for a variety each year were used to measure or observe grain appearance, amylose content and alkali digestibility, cooked rice texture using rheometer, gelatinization and viscosity of rice flour using amylograph, and eating Quality of cooked rice by sensory evaluation. Relationship between Quality characteristics showing large locational variation were analized to approach the long-term objective, rice grain Quality standardization. Percent white-center and white-belly grain of the same variety showed great variation between locations, but did not affect on 1000-grain weight, amylose content and alkali digestibility, amylogram and rheogram characteristics, and eating Quality of cooked rice. Positive correlationship were obtained between maximum viscosity and break down, and maximum viscosity and alkali digestibility. Set back was correlated negatively with maximum viscosity, break down and alkali digestibility. Rice samples having significantly lower values of maximum viscosity and break down and higher set back value at the same time showed higher ADV and lower texture palatability index (TPI) and viscousness/hardness ratio (Vi/H), and lower sensory evaluation score of cooked rice compared with those of rices having typically higher values of maximum viscosity and break down and lower set back value. When TPI, Vi/H and overall sensory eating score of cooked rices measured were divided into three categories, high, medium and low using deviation from locational mean value of a variety, many of rice samples having high TPI or high Vi/H showed medium or high in overall sensory eating score of cooked rice.

• Korean Journal of Food Science and Technology
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• v.25 no.5
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• pp.546-551
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• 1993

Rice flour obtained by four different milling methods, Pin mill. Colloid mill, Micro mill, and Jet mill, were used to investigate physico-chemical properties and product. Crude fat, ash, and protein contents of rice flours between different milling methods were similar. Blue value, amylose content, and damaged starch which related to properties of rice flour were reduced in the order that of Jet mill, Micro mill, Colloid mill, and Pin mill. Water absorption index, water solubility index, and water retention capacity increased as damaged starch increased. Hardness of gel(15%) is the highest value for Pin mill. The finer granules (Jet mill) had lower gelatinization onset(To) and peak(Tp) than any other rice flours. Those result are simillar with amylogram properties. Enthalpy of gelatinization increased as damaged starch increased. Jet mill had the highest score (p<0.05) of overall test in sensory evaluation and good paste properties.

• Korean journal of food and cookery science
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• v.7 no.4
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• pp.15-22
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• 1991

Changes in cooking properties of kidney beans A (reddish purple), B (mosaic), and C (pale yellow) during storage at $4^{\circ}$, $20^{\circ}$ and $30^{\circ}C$ for 5 months were examined. The weight and volume gains of raw beans during soaking at $30^{\circ}C$ were the greatest in kidney bean A followed by B and C, which were decreased from 3 months storage at $30^{\circ}C$. The weight gain, solid loss and hardness of cooked beans at $100^{\circ}C$ for 40 min decreased from 3 months of storage at $30^{\circ}C$ in all samples. The amylograms of whole kidney bean flours showed no peak and continuous increase of viscosity during heating. The kidney bean A showed the higher values in all reference points than kidney beans B and C which had similar amylogram patterns.