• Korean Journal of Food Science and Technology
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• v.27 no.5
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• pp.783-788
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• 1995

Cooked rices were frozen at four different rates(3, 5, 7 and 12 hr) of maximum ice crystal formation zone and stored at $-20^{\circ}C\;and\;-70^{\circ}C$ for 3 months. Freezing rate, storage temperature and storage period all affected the degree of retrogradation of cooked rice. As the maximum ice crystal formation zone increased from 3 hrs to 12 hrs, the degree of retrogradation of cooked rice increased from 14.9% to 40.0%. Further retrogradation occurred during the freezing storage and cooked rice stored at $-20^{\circ}C$ retrograded faster than that held at $-70^{\circ}C$. The hardness and adhesiveness of frozen cooked rice thawed in $40^{\circ}C$ water were measured. Hardness of the frozen cooked rice was higher than that of non-frozen sample and was higher at lower freezing rate. However, the hardness of cooked rice decreased after 3 months of storage. On the other hand, the adhesiveness decreased during the freezing processing, and adhesiveness decreased more rapidly at a higher freezing rate. However, the adhesiveness of cooked rice increased after 3 months of the storage, and the level of decrease was higher at $-70^{\circ}C$ than at $-20^{\circ}C$. After 3 months of storage, ice crystal size of frozen cooked rice became larger by recrystalization than that of frozen sample prior to storage. Microstructure of cooked rice was damaged by ice crystal formation and its growth when observed by scanning electron microscope.

• Korean journal of food and cookery science
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• v.23 no.5
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• pp.635-643
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• 2007

This study was carried out to investigate the quality of cooked rice prepared by-an electric pressure cooker (EPC) and an electric cooker (EC) during storage at different temperatures. Four rice cultivars were used (Ilpoom, Saechucheong, Sindongjin, and Sura). The cooked rice samples were stored at room and warm temperatures for 48 hr, and at refrigerator temperatures for 10 days. Immediately after cooking, the moisture content of the EPC rice was lower than that of the EC rice; yet pH was higher for the EPC rice. The L-value of the EPC rice was reduced due to an increasing b-value. The overall acceptability of the EPC rice was high; in particular, it scored high for a roasted nutty flavor and texture. During storage, moisture content and pH decreased regardless of the cooking method. L-, a- and b-values were similar at room and refrigerator temperatures over the entire period, whereas the a-value (greenness) of the EC rice stored at warm temperature slightly decreased and the b-value (yellowness) increased after 24 hr, resulting in a decreasing L- value. Also, sensory characteristics were not significantly different for the samples stored at room temperature for 48 hr; however, at warm and refrigerator temperatures, the sensory characteristics were significantly different after 24 hr and 3 days, respectively. In conclusion, the quality of the cooked rice was effectively preserved during storage at room temperature, and qualify deterioration oaf dependent on using warming equipment as well as the rice cultivar.

• 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).

• 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.

• Korean journal of food and cookery science
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• v.3 no.2
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• pp.50-58
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• 1987

This study was conducted to examine the changes of sensory and instrumental characteristics focusing on flavor and texture of cooked rice with Akibare(Japonica type) and Milyang 23(hybrid of Japonica and Indies) under two different storage temperatures. The changes of sensory characteristics were not significant throughout the storage of 70 days at $5^{\circ}C$, but were significant after 30 days storage at $30^{\circ}C$. The stepwise regression showed that stickiness, gloosiness and off-flavor of rice effected on overall preference in old rice stored at $30^{\circ}C$. As making storage temperature be tiger and period be longer, hardness, springiness, gumminess and chewiness were increased further but cohesiveness and adhesiveness were decreased in the texture changes of cooked rice measured by Instron.

• Korean journal of food and cookery science
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• v.4 no.2
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• pp.51-56
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• 1988

The sensory and instrumental characteristics of warm and cool cooked rices with pressure and electric cookers were examined. The types of rice varieties tested were Choucheong (traditional rice variety) Samgang and Seogwang (high-yielding rice varietis) The result of sensor evaluation revealed more significant differences in most of appearance, texture characteristics than flavour. The difference of sensory characteristics according to the types of cookers and the warm or cool cooked rices was greatest in Seogwang among three varieties. The instrumental measurement of cooked rices using instron showed that the difference between types of varieties and cookers was more clearly in cool cooked rices than warm ones. Especially hardness in instrumental characteristics revealed highly signficant difference. With regard to the correlation between instrumental and sensory characteristics, hardness had a significantly high correlation with texture while others had low ones.

• Korean journal of food and cookery science
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• v.18 no.5
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• pp.543-547
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• 2002

The purpose of this study was to investigate the effect of water extract of Gardenia jasminoides (WEGJ) on the sensory qualities, color value and shelf-life characteristics (pH, total no. of Bacillus and TBA value) of cooked rice. The total color difference(ΔE) was increased when WEGJ was added. The sensory dualities of cooked rice added with WEGJ had no significant difference in color, taste and torture compared with control group. The pH value of cooked rice addeded with 250 ppm and 500 ppm of WEGJ was less declined compared with control group. WEGJ at the concentration of 250 ppm and 500 ppm had an antimicrobial activity and WEGJ at 500ppm showed an antioxidant activity in cooked rice.

• The Korean Journal of Food And Nutrition
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• v.12 no.2
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• pp.142-149
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• 1999

Moisture absorption rate of rice according to the soaking time was higher at $25^{\circ}C$ than 4$^{\circ}C$ and the op-timum soaking time was 1hr at $25^{\circ}C$. When the ratios of added water for rice cooking were 1.3 in an elec-tric cooker and pressure cooker and 1.7 in an Dookbaeki sensory an mechanically evaluation of cooked rice were highly evaluated. The total number of peak on gas chromatography profile were 89 in an press-ure cooker 56 in an electric cooker and 83 in an Dookbaeki and major volatile compounds of cooked rice were aliphatic hydrocarbons cyclic hydrocarbons aromatic hydrocarbons aldehydes alcohols ketones and thiourea. Furan that is in sweety was not detected in volatile components of cooked rice of electric cooker.

• Korean Journal of Food Science and Technology
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• v.24 no.6
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• pp.623-624
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• 1992

The optimum ratios of added water for rice cooking at different amount of rice contents were studied with electric rice cooker. The optimum ratios of added water were $1.5{\sim}1.6$, 1.5 and 1.4 at 300g, 600g and 900g of rice contents. The optimum ratios of added water decreased as the rice contents were increased.

• Proceedings of the Korean Society of Community Living Science Conference
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• 2003.11a
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• pp.141-141
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• 2003

소득수준의 향상됨에 따라 환경과 건강에 대한 관심이 높아지면서 유기농산물에 대한 소비자 선호도가 증가하고 있음에도, 유기농산물의 품질에 대한 의구심 등으로 소비확대를 제약하는 요인들은 상존하고 있으며, 특히, 중요 식량자원인 쌀의 경우 유기농 쌀의 식품영양학적 품질 구명 연구는 미진한 실정이다 본 연구는 유기농 쌀의 품질 인증 및 식품영양학적 특성 구명에 기초자료로 활용할 목적으로 오리농법과 관행농법 및 표준시비법(대조구)으로 재배된 추청벼를 현미와 백미로 각각 도정한 후 영양성분 조성을 분석하였고, 동일조건에서 취반한 쌀밥의 관능적 특성을 조사하였다.