• Korean journal of food and cookery science
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• v.7 no.2
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• pp.7-18
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• 1991

This study was experimented saccharification process added malt extract solution into cooked sweet potato and potato with time, temperature and was tested reducing sugar changes, structural changes, pH and sensory evaluation about cooked shik-hae of rice, glutinous rice, potato, sweet potato. The results are summarized as follows: 1. Enzyme activity was highest in malt after four days of barley germination at a room temperature. 2. Electronmicroscopic observation indicated that raw starch granule of potato and that of sweet potato was 25-60$\mu\textrm{m}$ and 8~18$\mu\textrm{m}$ in size, respectively and its shape is oval and globular for potato and sweet potato respectively. 3. Reducing sugars were 1,682.6mg and 1,695.6mg in rice and glutinous rice, respectively, for 6-hour-saccharification at $50^{\circ}C$. Reducing sugars were 1,689.1mg and 1,497.8mg in sweet potato, potato, respectively, for 6.hour-saccharification at $60^{\circ}C$. 4. pH variation during saccharification for sweet potato and potato was pH 5.8~5.4. 5. Sensory evalution showed that there were more significant differences in sweety odor, roasted nutty taste and sweety taste of sweet potato among four samples than the other's color shininess.

• Korean Journal of Food Science and Technology
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• v.24 no.5
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• pp.511-514
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• 1992

The effects of soaking conditions (time and temperature) of rice on the water absorption behaviors and the consequent textural properties after cooking were investigated. Water absorption during soaking was completed in 30 min at $23^{\circ}C$, while the hydration continued up to 60 min at $4^{\circ}C$. The hardness (H) of the cooked rice decreased, while the stickiness (S) and S/H ratio increased with increased soaking time. Soaking at $23^{\circ}C$ gave higher values of S and S/H of cooked rice than soaking at $4^{\circ}C$. Soaking for $10{\sim}40\;min$ at $4^{\circ}C$ or for $10{\sim}20\;min$ at $23^{\circ}C$ resulted the value of S/H between 0.15 and 0.20, which had been found at acceptable textural parameters of the cooked rice.

• Korean journal of food and cookery science
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• v.14 no.4
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• pp.416-420
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• 1998

The Properties of cooked rice prepared by microwave oven was compared with those by pressure cooker There was no significant difference in sensory evaluation between microwave-cooked and pressure-cooked rices, however, the rice cooked by electric cooker was less preferred to others. The hardness of pressure-cooked rice was greater than others. As the storage time for cooked rice increased, the extent of gelatinization decreased, however, there were no significant differences among three samples.

• Korean journal of food and cookery science
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• v.33 no.2
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• pp.209-217
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• 2017

Purpose: The aim of this study was to compare the cooking properties of Bodeurami and Ilmi to promote consumption of rice. Methods: The properties of Bodeurami and Ilmi such as proximate composition, Hunter's color value, water absorption rate, and cooking properties as well as Hunter's color value, texture properties, and sensory evaluation of cooked rice were analyzed. Results: Crude protein, crude fat, and crude ash contents of Bodeurami and Ilmi were higher in brown rice than in white rice. Regardless of rice cultivars, L-value was lower, whereas a and b-values were higher in brown rice than in white rice. The water absorption rate of rice grains was higher in white rice than in brown rice and increased rapidly to 75 min for white rice and 4 hr for brown rice. Cooking properties, water absorption, and expansibility of white rice were higher than those of brown rice, and there were significant differences between Bodeurami and Ilmi. Immediately after cooking and after storage at warm ($70^{\circ}C$) and room temperatures ($25^{\circ}C$), hardness of cooked rice increased after storage, but was not significantly different between Bodeurami white rice and Ilmi brown rice. The sensory evaluation shows that Bodeurami brown rice scored the highest for taste, texture and overall preference. Conclusion: Thus, the results of this study shows that Bodeurami brown rice is characterized by high cooking quality without any mixed white rice, and Bodeurami white rice could be used for the rice processing industry as well as cooked rice.

• Korean journal of food and cookery science
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• v.21 no.3 s.87
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• pp.326-338
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• 2005

The purpose of this study was to investigate the effect of isolate soybean protein (ISP) and rice flour on the characteristics of rice noodles. As the levels of ISP and rice flour increased, water binding capacity, swelling power of rice noodle increased. In RVA, pasting temperature, Set back showed an increasing tendency with peak viscosity, holding viscosity, break down, final viscosity of rice noodle increased as the level of rice flour by decreasing. Peak time was not significant. The weight, water absorption and volume of the cooked noodles were decreased. The turbidity of rice noodle increased. The Hunter color L, a-values of the dried rice noodle decreased. Cooked rice noodle quality increased with by decreasing the level of rice flour level. B-values of dried rice noodle and cooked rice noodle increased. Texture profile analysis of cooked rice noodle showed an increase of hardness. Adhesiveness, cohesiveness of cooked rice noodles decreased with by decreasing the level of ISP and rice flour. Gumminess, springiness, chewiness were increased. Sensory evaluation, showed gloss was increased. Hardness and chewiness of the cooked ice noodles were increased. Adhesiveness was not significant. Color and overall- acceptability were increased. Relationship between sensory and mechanical examinations (The overall quality of sensory examination for gloss) had a negative correlation with the mechanical examination for b-value (p.0.05). Mechanical examination for b-value had a positive correlation of sensory evaluation for hardness, chewiness, which had negative correlation of sensory evaluation for color. Scanning Electron, Microscopes observation of rice noodle was showed that the size of the hole grown was increased with by increasing the level of rice flour. From the above results, the most advisable mixture ratio of rice noodle evaluation was can be derived as follows: 171g rice flour, 114g wheat flour, 15g soybean protein isolate, 120ml water, and 6g salt.

• Proceedings of the Korean Society of Crop Science Conference
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• 2017.06a
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• pp.295-295
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• 2017

Rice (Oryza sativa L.) is one of the most important food crops in the world. The eating quality of cooked rice is the most important trait japonica rice breeding in Korea. Rice varieties that produce kernels that are firm and fluffy after cooking are generally favored in countries such as India, Pakistan, and Indonesia. Whereas varieties with kernels that maintain its shape, glossiness, savory odor, stickiness, and tenderness when cooked are preferred in Korea. This study analyzed the major physicochemical components of rice grain associated with the eating quality of 20 japonica rice varieties. Physicochemical components such as the amylose content, protein content, amylographic characteristics of polished rice, and texture of cooked rice were tested using a Tensipresser as alternative indirect methods in determining rice eating quality. Evaluation of eating quality of cooked rice using sensory test was conducted with 20 well trained members. The 20 rice varieties in different eating quality showed amylose contents of 17~20%. The amylose content of rice varieties had negative correlation with peak viscosity, however positive correlation with setback viscosity was observed. The stickiness and adhesiveness of cooked rice showed correlation with the amylose content and amylopectin chain length distribution. Rice varieties with good eating quality showed less retrogradation of cooked rice and higher hot viscosity of rice flour in amylogram.

• Journal of the Korean Society of Food Science and Nutrition
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• v.46 no.6
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• pp.765-770
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• 2017

Green tea (Camellia sinensis L.) is consumed as a popular beverage worldwide, particularly in Asia. In this study, the effects of green tea powder addition on the antioxidant activities and texture properties of cooked rice were investigated. Texture analysis was carried out by texture profile analysis. Total polyphenols and total flavonoids were determined using spectrophotometric methods, and antioxidative activities were determined based on DPPH and ABTS radical scavenging activities, reducing power, and lipid peroxidation inhibitory activity. Antioxidant contents and antioxidative activities increased with a higher amount of green tea powder. However, there was no difference in texture properties between cooked rice with green tea powder and the control group. In conclusion, addition of green tea powder to cooked rice would be useful to increase antioxidant contents and antioxidative activities without alteration of texture properties.

• Proceedings of the Korean Journal of Food and Nutrition Conference
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• 2001.12a
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• pp.39-74
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• 2001

The endeavors enhancing the grain quality of high-yielding japonica rice were steadily continued during 1980s∼1990s along with the self-sufficiency of rice production and the increasing demands of high-quality rices. During this time, considerably great, progress and success was obtained in development of high-quality japonica cultivars and qualify evaluation techniques including the elucidation of interrelationship between the physicochemical properties of rice grain and the physical or palatability components of cooked rice. In 1990s, some high-quality japonica rice caltivars and special rices adaptable for food processing such as large kernel, chalky endosperm aromatic and colored rices were developed and its objective preference and utility was also examined by a palatability meter, rapid-visco analyzer and texture analyzer. The water uptake rate and the maximum water absorption ratio showed significantly negative correlations with the K/Mg ratio and alkali digestion value(ADV) of milled rice. The rice materials showing the higher amount of hot water absorption exhibited the larger volume expansion of cooked rice. The harder rices with lower moisture content revealed the higher rate of water uptake at twenty minutes after soaking and the higher ratio of maximum water uptake under the room temperature condition. These water uptake characteristics were not associated with the protein and amylose contents of milled rice and the palatability of cooked rice. The water/rice ratio (in w/w basis) for optimum cooking was averaged to 1.52 in dry milled rices (12% wet basis) with varietal range from 1.45 to 1.61 and the expansion ratio of milled rice after proper boiling was average to 2.63(in v/v basis). The major physicochemical components of rice grain associated with the palatability of cooked rice were examined using japonica rice materials showing narrow varietal variation in grain size and shape, alkali digestibility, gel consistency, amylose and protein contents, but considerable difference in appearance and torture of cooked rice. The glossiness or gross palatability score of cooked rice were closely associated with the peak. hot paste and consistency viscosities of viscogram with year difference. The high-quality rice variety “Ilpumbyeo” showed less portion of amylose on the outer layer of milled rice grain and less and slower change in iodine blue value of extracted paste during twenty minutes of boiling. This highly palatable rice also exhibited very fine net structure in outer layer and fine-spongy and well-swollen shape of gelatinized starch granules in inner layer and core of cooked rice kernel compared with the poor palatable rice through image of scanning electronic mcroscope. Gross sensory score of cooked rice could be estimated by multiple linear regression formula, deduced from relationship between rice quality components mentioned above and eating quality of cooked rice, with high Probability of determination. The ${\alpha}$ -amylose-iodine method was adopted for checking the varietal difference in 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, shelved the relatively fast deterioration of cooked rice. Generally, the better rice cultivars in eating quality of cooked rice showed less retrogiadation 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 rice. The softer gel consistency and lower amylose content in milled rice revealed the higher ratio of popped rice and larger bulk density of popping. The stronger hardness of rice grain showed relatively higher ratio of popping and the more chalky or less translucent rice exhibited the lower ratio of intact popped brown rice. The potassium and magnesium contents of milled rice were negatively associated with gross score of noodle making mixed with wheat flour in half and the better rice for noodle making revealed relatively less amount of solid extraction during boiling. The more volume expansion of batters for making brown rice bread resulted the better loaf formation and more springiness in rice bread. The higher protein rices produced relatively the more moist white rice bread. The springiness of rice bread was also significantly correlated with high amylose content and hard gel consistency. The completely chalky and large gram rices showed better suitability for fermentation and brewing. Our breeding efforts on rice quality improvement for the future should focus on enhancement of palatability of cooked rice and marketing qualify as well as the diversification in morphological and physicochemical characteristics of rice grain for various value-added rice food processings.

• Preventive Nutrition and Food Science
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• v.18 no.1
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• pp.67-75
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• 2013

Descriptive analysis and consumer acceptance tests were conducted with frozen (FCR), homemade (HCR), and aseptic-packaged (ACR) cooked rice products from two cultivars-IM and SD. FCR was prepared using a rapid freezing process, which may provide consumers with a quality similar to that of HCR. The intensity of the flavors of roasted, glutinous rice, rice cake, and rice starch and the textures of glutinousness, moistness, chunkiness, adhesiveness, and squishiness were all greater in the FCR as compared to the HCR and ACR (p<0.05) in IM and SD cultivars. The differences in sensory characteristics between the FCR and ACR were larger than the equivalent differences between the FCR and HCR. Overall consumer acceptance ratings for FCR in overall aspect, appearance, aroma, and texture were not significantly different compared to those for HCR (p>0.05); however, in most cases these factors showed significant differences when compared with ACR (p<0.05). From partial least square regression analysis, cooked rice was positively related to sweet, transparency, glossiness, roasted, glutinousness, chunkiness, moistness, glutinous rice, adhesiveness, rice shape, rice starch, and squishiness attributes but negatively related to raw rice, old rice, old rice aroma, a particle feeling, off-aroma, white color, scatteredness, slickness, size of cooked rice, and firmness attributes.

• Korean Journal of Food Science and Technology
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• v.48 no.5
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• pp.521-524
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• 2016

This study aimed to examine variations in the texture profile analysis (TPA) of cooked rice in relation to the instrumental parameter conditions. The TPA of four types of ready-to-eat, white rice products was conducted in two levels of compression ratio (30 and 70%) and cross-head speed (0.5 and 1.0 mm/s). The properties of the four rice products significantly or non-significantly differed, depending on the instrumental parameter condition. Agglomerative hierarchical clustering, based on the five TPA properties such as hardness, adhesiveness, cohesiveness, chewiness, and springiness, revealed that clustering of the four rice products varied with the instrumental parameter condition. Additionally, the ratio of adhesiveness to hardness, an index of rice texture quality, showed a variation depending on the two instrumental parameter conditions. In conclusion, our findings demonstrate that the texture profile, texture-based sample clustering, and the ratio of adhesiveness to hardness vary with the compression ratio and cross-head speed in the TPA.