• Preventive Nutrition and Food Science
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• 제3권3호
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• pp.234-240
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• 1998

This study attempted to determine the effect of various thawing methods and storage periods on the quality of froen cooked rice. Frozen cooked rice was thawed at four different methods, such as pressure cooking, conventional cooking, microwave heating and thawing at room temperature after 10 days, 30days and 90 days frozen storage. We conducted a physico-chemical analysis (moisture content, dehydration rates, degree of gelatinization, color value and texture) and sensory evalution 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 period of 90 days. However, the thawing method of pressure cooking caused high moisture content, rapid dehydration rates, and a high degree of gelatinization on the cooked rice. Thus, the desirabililty for the rice diminished becaused of the excess moisture content and the change of appearance and testure in the rice due to the high temperature. There were similiar quality characteristics to the cooked rice after forzen-thawing whether by conventional cooking or by microwave heating and just after cooking. Thawing at room temperature also caused a significant decrease in quality characteristics.

• 한국생활과학회지
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• 제5권1호
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• pp.81-88
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• 1996

가수량을 달리하여 취반한 멥쌀밥과 찹쌀밥을 저장하면서 관능적 특성을 비교한 결과 맛, 냄새에 대한 특성치들 보다는 대부분 텍스쳐에 대한 특성치들 보다는 대부분 텍스쳐에 대한 특성치들이 유의한 차이를 보였다. 또, 가수량이 증가할수록 견고성은 감소하였고 질음성과 풍만성은 증가하였으며 가수량 1.4배의 멥쌀밥과 1.2배의 찹쌀밥이 선호도가 가장 높았다. 저장기간이 길어지면 기계적인 특성치 중 견고성이 가장 유의한 차이를 보이며 증가하였고 멥쌀밥의 증가폭이 훨씬 컸다.

• Applied Biological Chemistry
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• 제40권5호
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• pp.422-426
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• 1997

자당 지방산 에스테르(sucrose fatty acid ester, $0{\sim}5%$, w/w) 또는 이소말토올리고당 (isomaltooligosaccharide, OS, $0{\sim}1.0%$, w/w) 첨가가 취반 후 $20^{\circ}C$ 저장$(0{\sim}12hr)$중 동진벼 쌀밥의 조직감에 미치는 영향을 경도(H),끈기(-H),끈기 대 경도의 비(-H/H) 및 탄성회복도(b/a)로써 조사하였다. 저장시간이 길어짐에 따라 저장 쌀밥의 H는 감소하였고, 대조구 보다 SE를 첨가한 쌀밥은 전반적으로 낮은 경도값을 보였으며 OS을 첨가한 쌀밥은 8시간 저장 이후에 낮게 나타났다. 쌀밥의 -H변화는 저장시간이 길어짐에 따라 첨가물의 농도에 관계없이 증가하였으며 SE를 첨가한 경우 저장초기에는 대조구에 비하여 작게 나타났으나 12시간 후에는 비슷하게 나타났다. OS를 첨가한 경우는 저장초기에 대조구와 비슷한 증가를 보였으나 저장말기에는 높게 나타났다. 저장시간에 따른 쌀밥의 -H/H변화는 -H변화와 같은 경향을 나타내었으며 쌀밥의 조직감이 가장 좋다는 -H/H값이 $0.15{\sim}0.20$의 구간에 들어가는 것은 대조구나 첨가물군 모두 10시간이 지난 후였다. b/a는 첨가물의 농도에 관계없이 저장시간이 길어짐에 따라 감소하였으며 대조구와 큰 차이는 나타나지 않았다. $4^{\circ}C$에서 15일간 저장 후H는 대조구인 경우 5.83kg인 반면 SE의 농도가 0.25및 0.5%에서는 각각 5.58및 5.43kg,로 나타났으며 OS의 경우 0.5%와 1.0% 농도에서 각각 5.73과 5.74 kg,이었다.

• 한국작물학회:학술대회논문집
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• 한국작물학회 2017년도 9th Asian Crop Science Association conference
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• pp.269-269
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• 2017

Germination is one of the techniques used to enhance the texture properties and nutritional value of the brown rice (BR). Therefore, germinated BR (GBR) has received significant attention during the last decade. Physicochemical and cooking properties of brown rice were examined before and after germination. Germination raised the cooking properties, such as water absorption, expanded volume and soluble solid of cooked BR (brown rice). The texture, measured using tensipresser, was significantly improved by germination. The hardness of cooked BR was decreased by germination, but the GBR was sticker. In RVA, all viscosity value (peak viscosity, break down, set back, and final viscosity) of germinated rice flour was also reduced while gelatinization temperature did not change. Amylose content and amylopectin chain length distribution of BR starch were slightly changed by germination. Overall results revealed that germination was an effective tool to improve texture and cooking properties of BR.

• 한국식품과학회지
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• 제27권5호
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• pp.783-788
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• 1995

본 연구는 동결속도 및 동결저장온도가 취반된 쌀의 이화학적 특성에 미치는 영향을 살펴보고자, 단열재를 이용하여 최대 빙결정 형성신간이 3시간, 5시간, 7시간 그리고 12시간인 동결속도로 24시간 동안 동결하였고, 동결된 시료는 각각 $-20^{\circ}C$와 $-70^{\circ}C$의 냉동고에서 3개월간 저장하여 동결저장동안에 각 시료의 노화도 그리고 조직감의 변화를 조사하였다. 동결된 쌀밥의 미세구조 및 표면구조는 빙결정을 동결치환에 의해 제거한후 scanning electron microscopy(SEM)으로 관찰하였다. 취반된 쌀의 노화도는 동결속도, 동결저장온도, 저장기간에 따라 큰 영향을 받아 최대 빙결정 형성시간이 3시간에서 12시간으로 길어짐에 따라 노화도는 14.85%에서 40.00%로 증가하였고, 동결된 쌀밥의 동결저장 중 노화도는 $-20^{\circ}C$에서 저장한 것이 $-70^{\circ}C$의 경우보다 노화된 정도로 크고, 빠른 진행을 보였다. 동결된 시료를 해동한 후의 경도는 동결시키지 않은 대조구와 비교할 때 크게 증가하였으며, 또한 동결속도가 늦어질수록 더 큰 증가를 보였다. 하지만, 3개월간 저장한 후에는 경도가 다시 감소하였다. 한편, 부착성은 대조구와 비교하여 24시간 동안 동결된 쌀밥에서는 감소하였으며 3개월간 저장한 후에는 다시 증가하는 경향을 보였다. 동결된 취반된 쌀의 빙결정의 크기는 동결속도가 늦어짐에 따라 커졌고 그 수는 상대적으로 적었다. 또한 3개월간 저장한 후에는 얼음의 재결정화에 의해 시료의 빙결정은 더욱 커져 취반된 쌀의 구조가 많이 파손되었음을 확인할 수 있었다. 결론적으로 최대빙결정형성시간을 단축하여 취반된 쌀을 동결시키는 것과 낮은 온도에서 저장하는 것이 빙결정의 형성과 성장에 따른 전분의 노화와 조직감의 변화를 억제할 수 있다고 판단되었다.

• 한국식품영양학회지
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• 제13권1호
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• pp.21-27
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• 2000

In order to investigate the changes of rice qualities during 4 years storage of paddy in warehouse of normal temperature condition. As storage period go by, head ratio was deduced and broken rice was increased according as a change of temperature during the long term storage. A color of rice was became more dark gray than that of entering time as L value was decreased from 64.07 to 61.62 a 4 years late. As a results of studies on the cooking quality of milled rice, water uptake ratio and expanded volume were increased in proporation to storage period, wherease total solids and iodine blue value were decreased. In the characteristic of texture of cooked rice, viscosity/hardness ratio(-H/H) had a decreasing tendency, while adhesiveness and cohesiveness increased with increased storage time. The qualities of cooked milled rice studied were sensory attributies of odor, taste, stickiness and appearance which were evaluvated by multiple comparsion method. The sensory results showed that all of descriptions were deterirated with a increased storage period. The taste and stickiness were changed from good score to bad score a 2 years later.

• 한국식생활문화학회지
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• 제24권1호
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• pp.69-76
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• 2009

This study was conducted to determine the optimal cooking conditions for brown rice using an electric pressure rice cooker. The effects of steeping conditions and cooking pressure on the hydration, gelatinization, texture and palatable properties of cooked brown rice were evaluated. Based on water uptake and DSC data, the optimal steeping time and temperature for brown rice were determined to be 25 minutes and ${\sim}60^{\circ}C$, respectively. The cooking conditions for brown rice were then divided into the following 6 categories: steeping at $25^{\circ}C$ for 25 minutes and cooking at an atmospheric pressure of 1.7 (25P) or 1.9 (25HP), steeping at $57^{\circ}C$ for 25 minutes and cooking at an atmospheric pressure of 1.7 (57P) or 1.9 (57HP), steeping at $85^{\circ}C$ for 15 minutes and cooking at an atmospheric pressure of 1.7 (85P) or 1.9 (85HP). The susceptibility of cooked brown rice starch to degradation into maltose by ${\alpha}$-amylase, which is related to the degree of gelatinization and in vitro digestibility, were then determined. The amount of maltose produced by cooked brown rice samples was highest in the 57HP group, followed by the 57P and 85HP groups. Storing cooked brown rice at $73^{\circ}C$ for 24 hours resulted in significantly higher amounts of starch being degraded into maltose in the 57P, 57HP and 85HP groups than in the other groups. Textural analysis demonstrated that the 57P, 57HP and 85HP groups had significantly lower gumminess and chewiness values when compared to the other groups, and that 57HP received had the lowest hardness of all treatments. These results were confirmed by the results of the sensory evaluations. Furthermore, the 57P and 57HP groups were found to have a higher glossiness, stickiness aroma and taste score than the other groups. These findings were taken to indicate that steeping conditions and pressure exerted a positive synergistic effect on the cooking quality of brown rice. The texture analyzer also revealed that storing the cooked rice at $73^{\circ}C$ for 24 hours only led to significantly lower scores in gumminess, hardness and chewiness in the 57P and 57HP groups, which indicates that these groups underwent a lesser degree of retrogradation than other groups. Taken together, the results of the present study demonstrate that steeping brown rice at $57^{\circ}C$ for 25 minutes and a higher cooking pressure improved the palatability and in vitro digestibility of brown rice significantly.

• 한국작물학회지
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• 제35권2호
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• pp.137-145
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• 1990

국내에서 재배되고 있는 벼 6품종을 대상으로 품종별로 8-20 지역에서 1987년과 1988년에 생산된 쌀을 각각 수집하여 그들의 외관, 아밀로스함량 및 알칼리붕괴도, 아밀로그라프에 의한 쌀가루의 호화 및 점성특성과 레오메타를 이용한 밥알의 조직감(Texture)을 조사하고 관능검사법에 의한 식미평가를 실시하여 이들 상호간의 관계를 검토하였다. 1. 동일품종내에서는 재배지역에 따른 심복백미비율의 변이가 백미천립중, 쌀알의 아밀로스 함량과 알칼리붕괴도, 쌀가루의 아밀로그람특성, 밥알의 레오그람특성 및 식미와 각각 독립적으로 나타났다. 2. 재배지역에 따른 변이정도가 컸던 형질들간의 단순상관관계를 보면 아밀로그람특성 중 최고점도와 break down간에 정의 상관, 최고점도와 set back간, 그리고 set back과 break down간에는 부의 상관이 인정되었고 알칼리붕괴도와 break down간, 알칼리붕괴도와 최고점도간에는 정의 상관, 그리고 알칼리붕괴도와 set back간에는 부의 상관이 인정되었다. 3. 아밀로그람특성 중 최고점도와 break down 값이 낮았고 동시에 set back 값은 높았던 3지역 쌀은 최고점도와 break down 값이 높고 set back 값이 낮았던 3지역 쌀에 비하여 알칼리붕괴도는 높고, 레오그람특성 중 식미지수(TPI)와 점성/경도비율(Vi/H)은 낮았으며 관능검사법에 의한 종합식미에서도 낮은 점수를 받았다. 4. 레오메타로 조사한 점성/경도비율과 관능검사로 평가한 종합식미를 품종별 지역평균치보다 상급, 하급 그리고 평균치정도의 3등급으로만 나누어 두 형질간의 간계를 검토한 결과 점성/경도비율이 상급인 쌀은 종합식미가 평균치정도 또는 상급으로 판정받은 경우가 대부분이었다. 레오메타특성 중 식미지수와 종합식미와의 관계도 점성/경도비율에서와 비슷한 경향을 보였다.

• 한국식생활문화학회지
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• 제38권5호
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• pp.326-335
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• 2023

This study aims to analyze the sensory characteristic of cooked rice made with 10 types of rice varieties produced in South Korea using descriptive analysis. Twelve subjects who cook rice regularly, at least once a week, were recruited for the study and participated as descriptive panelists. A total of 29 descriptive terms were developed to describe the sensory characteristics of cooked rice. The findings showed that there were significant differences in the sensory attributes, specifically the appearance and texture attributes among the rice varieties. Among the varieties, Haedeul, Ilpum, and Koshihikari were observed to have a large quantity of rice germ and a relatively yellowish appearance. In contrast, Samkwang, Chamdream, and Yeonghojinmi were relatively whiter than the other samples. Odae, Saecheongmoo, and Sindongjin were rated high in the attributes of roughness, hardness, and chewiness, and Jinsang was rated high in moisture, bitterness, stickiness, and wholeness of rice grains. The differences in the appearance and texture of these rice varieties are likely to significantly impact consumer preferences. Furthermore, the development of customized menus based on the sensory characteristics of the different varieties of rice could encourage consumers to purchase these varieties.

• 한국작물학회:학술대회논문집
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• 한국작물학회 2017년도 9th Asian Crop Science Association conference
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• pp.287-287
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• 2017

The objective of this study was to evaluate difference of quality properties of between fresh cooked rice and re-heated cooked rice after retrogradation. Nine rice varieties raised by NICS were compared the properties of physicochemical, texture, sensory evaluation, toyo glossiness value, pasting properties. Among nine rice cultivars, the changes of weight and length-width ratio of after soaking as well as cooking showed how water absorbed in each rice granule. The amount of water absorption after soaking was highest in Wolback (semi-waxy), Hiami and lowest in Samgwang, Seonpum, Ilpum. After cooking, the amount of water absorption was high in Dasan 1 and Andabyeo, however low in Ilpum. In the length-width ratio after soaking, Wolback (semi-waxy cultivar) and Anda (indica cultivar) increase their volume relatively as their shape are while others increased more in length than width. Among cooked rice, the highest value of length-width ratio shows in Anda, Dasan1, Hiami and Seonpum, the Wolbak was similar to that of non-glutinous rice. After cooking, the others stored at $10^{\circ}C$ for 16 hours for retrogradation (imitated at convenience store). Then re-heated using by microwave. Pasting properties were considerably affected by storage temperature and periods of rice. The setback showed in the following order: Wolback (-92.25 RVU, the lowest retrogradation) < Seonpum (-35.20) < Chindle (-22.08) < Jungsanggold (-21.98). Toyo glossiness value of cooked rice showed in the following order: Chindle (82.40) > Samgwang (79.43) > Hiami (79.23). Sensory evaluation of re-heated rice of Jungsanggold, Samgwang, and Chindle were 78.97, 78.36, and 77.35, respectively. Hardness, elasticity, and toughness of re-heated rice ware increased compared to cooked rice, whereas cohesiveness was decreased. Hardness and elasticity is higher in Seonpum, Dasan1 and Hiami, toughness is higher in Jungsanggold, Samgwang and Wolbak. Cohesiveness of Jungsanggold and wolbak showed higher than others.