• The Korean Journal of Food And Nutrition
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• v.31 no.5
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• pp.760-765
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• 2018

In order to observe physical properties of rice depending on reheating, the study cooked rice developed for high quality cooked rice and analyzed physical properties of rice depending on reheating following 24 hr refrigeration. As a result of palatability of cooked rice, Samgkwang had the lowest hardness, while Daebo and Haiami had the highest one. With respect to adhesiveness, toughness and stickiness, Sindongjin exhibited lowest properties. After cooking each rice by cultivars, the study observed their color, texture properties, and microstructure immediately after cooking, after 24 hr of refrigeration and further on. Lightness of cooked rice tended to drop because of refrigeration and reheating. Analysis of texture properties after cooking revealed that Haiami marked the highest points in all categories. When stored for 24 hr after cooking, hardness, viscosity and chewiness increased in cooked rice followed by a decrease after reheating. Observation of the microstructure of cooked rice using a scanning electron microscope revealed that Haiami had its particles in the center as closely condensed. It was apparent that all the cultivars formed stoma in an obvious manner because of refrigeration and reheating. The results of the present study show that physical properties of cooked rice varied according to reheating after cooking and storage depending on the inherent characteristics of rice cultivars.

• Journal of the Korean Society of Food Science and Nutrition
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• v.25 no.1
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• pp.63-68
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• 1996

• The Korean Journal of Food And Nutrition
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• v.17 no.3
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• pp.266-271
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• 2004

In this study, rice was cooked with 0%, 0.5%, 1.0% and 2.0% green tea powder content to improve functionality of cooked rice. The effects of green tea powder content on the physical, texture and sensory characteristics of cooked rice were examined. Moisture contents of cooked rice with green tea powder were decreased with increasing amounts of added green tea powder. Initial pasting temperature of rice powder was showed an increase with increasing amounts of added green tea powder, besides peak viscosity was decreased. The solubility and swelling power were decreased with increasing amounts of added green tea powder. The color of cooked rice was darkened gradually with the increasing amounts of added green tea powder, and showed the dark green. Sensory adhesiveness was gradually decreased with the increasing amounts of added green tea powder, and cohesiveness, gummness, chewiness and hardness were increased. Sensory glassiness, overcook, stickiness and hardness had lower score than control group, but sensory color, flavor and overall acceptability had higher score with addition of 1.0% and 2.0% green tea powder. Concludingly, in items of overall sensory, cooked rice with 1.0% green tea powder showed the best result.

• Korean Journal of Food Science and Technology
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• v.23 no.4
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• pp.498-502
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• 1991

The relationships between the textural properties of cooked rice and hot water-solubles of rice or rice flour were studied. The amounts of solubles or soluble amylose among japonica varieties were similar, but those among Tongil type varieties were different. At the same heating conditions, japonica varieties showed higher contents of solubles as well as soluble amylose than Tongil varieties. The solubles and soluble amylose from rice or rice flour showed a negative correlation with hardness but a positive correlation with adhesivess of rice cooked with optimum water.

• Korean journal of food and cookery science
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• v.23 no.5
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• pp.761-769
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• 2007

The purpose of this study was to provide the sensory profiles for cooked rice varieties, with 3 types of functional rice and 4 types of ready -to -eat rice, using descriptive analysis. Eighteen descriptors as well as reference standards were developed. The cooked functional rice, ready-to-eat rice, and plain cooked rice were separated into 4 groups by PCA. PC1 & PC2 explained 65% of the total valiance. PC 1 was responsible for the highest percentage of separation based on the texture intensities. The cooked functional rice showed higher intensity for hardness and roughness. The ready-to-eat rice A, B, and C samples had higher intensities in terms of moistness, glossiness, and moisture content, as well as sour and raw rice flavor. The ready-to-eat rice D sample had low grain wholesomeness, and high intensity for raw rice flavor. Finally, the plain cooked rice had more roasted and burnt rice flavor.

• Korean Journal of Food Science and Technology
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• v.28 no.4
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• pp.720-729
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• 1996

Effect of the cellulase treatment on the physicochemical properties of three varieties of rice (chucheongbyeo, chosengtongilbyeo and IR 36) and the texture of cooked rice were investigated. The swelling power and solubility of the rice flours were increased and amylographic viscosities, especially cold viscosities were decreased by cellulase treatment in all varieties. Gel chromatography of soluble carbohydrates from cellulase-treated rice flours on sepharose 2B-CL showed a singificant increase of low molecular weight $(10^{4})$ fraction which might be produced upon hydrolysis in endosperm cell wall constituents. The hardness of cooked rices prepared from cellulose-treated rices significantly decreased.

• Korean Journal of Food Science and Technology
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• v.20 no.1
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• pp.59-62
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• 1988

The correlations of rice properties and the texture characteristics of hot($70^{\circ}C$) and cold($20^{\circ}C$) cooked rice were investigated with Japonica and J/Indica rice each of 6 varieties. No significant differences in textural properties between Japonica and J/Indica cooked rices were observed. The hardness of cold cooked rice was positively correlated with setback(r=0.613) of rice flour but not correlated with amylose content and the other chemical properties of starch or rice flour.

• Korean journal of food and cookery science
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• v.24 no.2
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• pp.188-197
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• 2008

This study was carried out to determine the optimal cooking conditions for various rice cultivars (Ilpoom, Saechucheong, Sindongjin, and Sura-top rice) using trial preparations with different soaking times (0, 30, and l20min) and cooking equipment (electric pressure cookers, electric cookers, gas pressure cookers, iron pots, and stone pots). In adddition, the texture and sensory characteristics of the rice prepared with the electric pressure cookers, gas pressure cookers, and stone pots were analyed. The results showed that the moisture, amylose and physicochemical compositions of the four rice varieties were similar. According to RVA, the Sura, cultivar had generally high viscosity, and the Ilpoom, cultivar presented the highest hot and peak viscosities. Saechucung had the highest initial gelatinizing temperature and Sindongjin showed the greatest setback. The optimal amounts of added water as well as heating conditons were dependent on the rice varieties, soaking times, and cooking equipment. A longer soaking time reduced the hardness of the cooked rice, amount of added water, and the heating time. The pressure cooking equipment provided the best cooked rice texture, reduced the affect of the soaking time, and decreased the heating time. In general, all the variaties of cooked rice had high overall acceptability, which tended to increase when the rice was soaked for 30min prior to cooking, had a 1.2-fold amount of water to rice added, and was cooked in the pressure equipment.

• Korean Journal of Food Science and Technology
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• v.21 no.4
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• pp.486-491
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• 1989

The textural properties of cooked rice and the molecular weight distribution of amyloses of three rice cultivars different in cooking quality were investigated by the method involving rheometry and gel chromatography he tested rice cultivals were Chunmabyeo (short grain), Yongmunbyeo (medium grain) and Mahatma (long grain) The cooked rice prepared with Mahatma was higher in hardness and lower in adhesiveness than those prepared with the other two cultivars. The molecular wright distribution of amylose from Mahatma was found to be higher than those from the other cultivars.

• The Korean Journal of Food And Nutrition
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• v.36 no.6
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• pp.581-587
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• 2023

Brown rice has various health benefits; however, it is more difficult to cook and has a harder texture as compared to milled rice. In this study, the effect of the sous-vide cooking method on starch retrogradation and textural properties of brown rice was investigated by comparative analysis with conventionally cooked brown rice based on moisture content assay, evaluation of the textural property analysis, and differential scanning calorimetry (DSC). The results of the study are as follows: First, the moisture content of sous-vide cooked brown rice was higher than in the conventionally cooked brown rice. Second, the sous-vide cooked brown rice has lower hardness, higher adhesiveness, and lower retrogradation enthalpy during storage than conventionally cooked brown rice. Finally, the retrogradation properties of cooked brown rice during storage were analyzed by DSC. The enthalpy increased more rapidly in the case of conventional cooked brown rice, reaching 1.58 J/g after 3 days of storage. This indicated that sous-vide cooking is effective in preventing retrogradation of rice during storage.