• Journal of the Korean Home Economics Association
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• v.38 no.3
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• pp.121-130
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• 2000

This study attempted to determine the effects of sucrose, NaCl and acetic acid on the quality characteristics of cooked rice stored at 20$\^{C}$ for 72 hours. It conducted a moisture content, color value, texture and RVA(Rapid Visco Analyser) viscosity on stored cooked rice. Moisture contents of all groups ecreased during storage and that of cooked rice with NaCl were significantly lower than that of other groups. In color, lightness(L) of cooked rice with various additives seemed higher than that of control group and reduced b value of cooked rice with acetic acid showed that the color became less yellow. In texture, the hardness of cooked rice with NaCl and sucrose was higher than that of control group, whereas that of cooked rice with acetic acid was similar to that of control group. Adhesiveness of cooked rice with acetic acid was higher than that of other groups and it was shown that texture could be improved by the addition of acetic acid. The initial viscosity of cooked rice with acetic acid was markedly higher than that of other groups and finial viscosity was lower than that of other groups. It seemed that addition of acetic acid could retard the retrogradation of stored cooked rice.

• The Korean Journal of Food And Nutrition
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• v.8 no.4
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• pp.330-334
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• 1995

A various aseptic packaged cooked rice prepared In Korean rice was developed for extending shelf-life at room temperature. Data of proximate composition showed no significant difference between cultivars except moisture of cooked rice. The optimal condition of added water content for aseptic packaged cooked rice was 1.3 times of rice while 1.5 times for cooked rice and microwave heating. Hardeness of cooked rice was decreased in order of Dongjin, Odae, Chuchung, Kyaehwa, Ilpoom. Sensory evaluation results showed that Ilpoom had a best result while Odae for storage time (7 days).

• Korean Journal of Food Science and Technology
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• v.18 no.1
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• pp.38-41
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• 1986

Sensory characteristics of cooked rites of one waxy variety and three nonwaxy varieties, Akibare (Japonica), Milyang 23 (J/Indica) and Milyang 30 (J/Indica) were evaluated in terms of odor, taste, appearance and texture. Sensory evaluation of cooked rites indicated that the cooked waxy rice was more watery, gloss, sticky, smooth and gummy in appearance and texture than nonwaxy cooked rites. Among the nonwaxy rites, Akibare was well balanced in all of the 12 descriptions of sensory quality. Milyang 30, generally recognized as having inferial eating quality, had the poorest quality in texture and appearance. The ratio of water addition to rice for cooking affected significantly to texture and appearance of cooked rice while the flavor remained comparatively unchanged.

• Korean Journal of Food Science and Technology
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• v.27 no.5
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• pp.757-761
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• 1995

The relationship between the molecular structure of rice starch and the texture of cooked rice was investigated using hot-water soluble rice starch. The structure of hot-water soluble starch bound amylose which was composed of small molecular weight and amylopectin which was composed of chain length of $\overline{DP}\;10{\sim}20$, and the average composition of amylose : amylopectin was 7 : 3. The molecular weight of amylose was the smaller and super long chain of amylopectin was the fewer, the extractable ratio of hot-water soluble rice starch was the higher. And hot-water solubility of rice starch be responsible for molecular structure of starch. On the texture of cooked rice, the extractable ratio of hot-water soluble rice starch was the higher, the hardness was the lower and the adhesiveness was the higher. The results suggest that the molecular structure of rice starch could be responsible for the texture of cooked rice.

• Journal of the Korean Society of Food Science and Nutrition
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• v.25 no.5
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• pp.810-816
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• 1996

This study was conducted to measure the hydration characteristics at $20^{\circ}C$ and investigated the effect of water to rice ratio(v/w) on the texture properties of cooked rice of ten different varieties based on maturity. Water absorptions during soaking were completed between 30min and 35min at $20^{\circ}C$. The ranges of equilibrium moisture content were between 0.3247g $H_2O/g$ dry matter and 0.3577g H201g dry matter. During the cooking process, the water content of cooked rice increased 6~7% with increased the ratio of water to rice from 1.4 to 1.6(v/w). The hardness(H) of cooked rice decreased, while the stickiness(-H) and -H/H ratio increased with increased ratio of water to rice.

• Korean Journal of Food Science and Technology
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• v.30 no.3
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• pp.562-568
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• 1998

Rice (Dongjin-byeo) added with black rices (Chindo and Suwon-415) was cooked and the changes of texture and color of this cooked rice were investigated by texture analyser and color & color difference meter. The hydration time to come to the equilibrium condition was at least 11 hr in black rices. The optimum ratio of water to cooked rice added with black rice was 1.6 (ratio of water to rice) and the hardness of cooked rice added with 5% Chindo black rice was $5.66\;kg_f$. Regardless of ratio of water to rice, Hunter a value increased as the ratio of black rice addition to rice increased, while L value decreased. The color elution rate of Suwon 415 was 4 times greater than that of Chindo black rice. The pH of the steep water of Suwon 415 at $20^{\circ}C$ during 120 min decreased from pH 6.40 to pH 6.16 as the steeping time increased. The optimum heating time by microwave oven of cooked rice added with black rice was between $90{\sim}120\;sec$ to recover the original texture after cold storage treatment of 7 days.

• Journal of the Korean Home Economics Association
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• v.35 no.2
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• pp.147-157
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• 1997

It attempted to determine the effect of various thawing methods, such as pressure cooking, conventional cooking, microwave heating and thawing at room temperature, on the quality of frozen cooked rice using Nongan variety of rice. These effects were analysed at three different periods-after 10 days, 30 days and 90 days. It conducted a physico-chemical analysis(moisture content, dehydration rates, color value and texture) and sensory evaluation o the frozen-thawed cooked rice. The study showed that there were no significant differences on the frozen-thawed cooked rice. The study showed that there were no significant differences on the quality characteristics of frozen-thawed cooked rice during the storage of 90 days. However, the thawing method of pressure cooking caused high moisture content and decrease in hardness on the cooked rice, the desirability for the rice didn't diminish compared with the cooked rice just after cooking. the quality characteristics of the cooked rice after frozen-thawing by conventional cooking and microwave heating were similar with that of the cooked rice just after cooking. thawing at room temperature caused a significant decrease in quality characteristics.

• Journal of the Korean Society of Food Science and Nutrition
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• v.33 no.3
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• pp.582-586
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• 2004

Cooked rice for immunosuppressed patients was irradiated at 0, 5 and 10 kGy, and investigated on the irradiation effect on color, texture, and shelf-life during storage at 3$0^{\circ}C$. Yellowness was significantly increased in cooked rice with the increase of storage period and irradiation dose (p<0.05) and the ratio of adhesiveness/hardness of cooked rice was decreased by irradiation at 10 kGy. The result of total plate count of non-irradiated cooked rice was 7 log CFU/g and that of 5 kGy irradiated cooked rice on 7 day storage was 4 log CFU/g, while that of 10 kGy irradiated sample was not detected even at the end of storage. Irradiation with 5 kGy on cooked rice is proper to prolong the shelf-life considering color, texture, and it was extended to over a month. Further research is necessary to apply the high-dose irradiation for long-term preservation to inhibit color and texture change.

• Applied Biological Chemistry
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• v.38 no.6
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• pp.563-569
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• 1995

Effect of protease and 2-mercaptoethanol treatment on the texture of cooked rice was investigated. Hardness, chewiness and gumminess of cooked rice were decreased by reducing the disulfide bonds of protein using 2-mercaptoethanol. Protease-treated rice grains, when cooked, showed more favorable results in stickiness measured by Instron, hardness measured by rheometer and sensory acceptability of cooked rice. Water content and volume expansion of cooked rice were increased by protease or 2-mercaptoethanol treatment. This results suggested that the textural characteristics of cooked rice may be influenced by surrounding or closely associated protein.

• Journal of the East Asian Society of Dietary Life
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• v.22 no.6
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• pp.782-794
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• 2012

The objective of this study was to determine the optimal conditions for preparation of cooked brown rice by blending brown rice, white rice and glutinous rice to improve the palatability. Formulations composed of brown rice (10~100%), white rice (0~90%) and glutinous rice (0~90%) were generated from an extreme-vertices of mixture experimental design, which showed ten experimental points for brown rice, with white rice and glutinous rice as the independent variables. The sensory evaluation, color, and texture profile analysis (TPA) of cooked brown rice and pasting characteristics of blending cereals flour were measured as response variables. Regression analysis showed that all responsible variables fit linear, quadratic or special cubic models (p<0.1), except for the cohesiveness of TPA. The goals of optimization of the blending ratio of brown rice, white rice and glutinous rice were given as appearance, flavor, texture and overall acceptability (lower: 5.50, target: 6.62). The optimal conditions were determined to be 34.55% brown rice, 42.71% white rice and 22.74% glutinous rice.