• Journal of Biosystems Engineering
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• v.36 no.4
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• pp.267-272
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• 2011

The latent heat of vaporization in rough rice, brown rice, white rice and rice hull was calculated by Clausius-Clapeyron equation, which does not require complex constraints as in Othmer method. Equilibrium relative humidity and ratio of the latent heat of vaporization with ln$P_{\upsilon}$ and ln$P_S$ were estimated with moisture contents ranging from 10% (d.b.) to 36% (d.b.) with 2% (d.b.) increment and temperatures ranging from $10^{\circ}C$ to $50^{\circ}C$ with $2.5^{\circ}C$ increment. An empirical equation for calculating the latent heat of vaporization in rice was developed as a function of moisture content and temperature. The equation agreed well with the calculated results. The ratio for latent heat of vaporization were the greatest for white rice while they were similar among rough rice, brown rice and rice hull.

• The Korean Journal of Food And Nutrition
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• v.30 no.2
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• pp.336-344
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• 2017

The physical characteristics of gluten-free rice bread, commercial rice as well as wheat bread marketed in Korea were delineated, a sensory descriptive analysis performed, and a consumer acceptability study conducted. Both the specific gravity and color of gluten-free rice bread were higher than those of commercial rice and wheat bread. The sensory descriptive analysis revealed that the adhesiveness, fracturability, fermentation odor, and the powdery mouthfeel of gluten-free rice bread were higher than those of commercial rice and wheat bread. In contrast, the sweet odor, sweetness, egg taste, butter taste, and milk taste of gluten-free rice bread were lower than those of commercial rice and wheat bread. The consumer acceptability results revealed differences regarding odor, appearance, taste, texture, and overall acceptance between a blind test and an informed test of gluten-free rice bread, commercial rice, and wheat bread. The consumer acceptability findings were associated with those of the sensory descriptive analysis. In overall, the results indicated that the quality of gluten-free rice bread can be improved by controlling the decrease of adhesiveness, fracturability, and powdery mouthfeel.

• Food Science and Biotechnology
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• v.17 no.1
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• pp.66-71
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• 2008

A total of 284 milled rice (MR) marketed in Korea were analyzed for grading characteristics (head rice, broken kernels, chalky kernels, and damaged kernels%), color characteristics (L-, a-, b-values, and whiteness), protein content (%), and the cooked rice (CR) sensory quality to investigate the key characteristics affecting the overall sensory quality of rice marketed in Korea. Relatively high correlation with the overall sensory quality of the CR was found in color characteristics such b-value of the CR (r=-0.779) and MR (r=-0.545), the a-value of the CR (r=0.513), and the whiteness (r=0.298) of the MR, compared to protein (r=-0.150), and the moisture (r=0.158) contents of the MR and the percentage of head rice (r=0.195). Partial least squares (PLS) regression of the CR b-value with various characteristics of the MR showed that CR b-value was increased with MR b-value effectively, followed by protein content, damaged kernels, chalky kernels, and colored kernels of MR while it was decreased with whiteness and moisture content for the MR.

• Korean Journal of Food Science and Technology
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• v.34 no.2
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• pp.213-219
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• 2002

This study was investigated cooking conditions of cooked milled rice added 5%, 7%, 9% and 11% ratios of waxy black and glutinous rices. The L value (lightness) of cooked milled rice added waxy black and glutionus rices were decreased according to increase added ratios, the a value (redness) of waxy black rice was decreased and b value (yellowness) of glutinous rice was increased while waxy black rice was decreased. In case of cooked milled rice added 9% glutinous rice, it was showed the highest values for springiness, cohesiveness, chewiness, adhesiveness and adhesiveness/hardness ratio except gumminess and hardness and all parameters of waxy black rice in texture analyser was showed the highest values at 9%, but the other parameters except cohesiveness were no significant difference at p<0.05 level. In sensory evaluation, the cooked milled rice added 9% glutinous rice was showed the highest values for flavor, clumpiness and taste and 11% glutinous rice was showed the highest values for color, glossiness, cohesiveness, hardness, adhesiveness and acceptability. Also the cooked milled rice added 9% waxy black rice was showed the highest values for cohesiveness, taste and acceptability and 11% waxy black rice was showed the highest values for flavor, color, glossiness, clumpiness, hardness and adhesiveness. Correlations between sensory parameters of cooked milled rice added waxy black rice and glutinous rice were found a significant relationship between taste and acceptability and the correlation coefficients of cooked milled rice added waxy black rice and glutinous rice were r=0.7153 and r=0.5760, respectively.

• Korean Journal of Soil Science and Fertilizer
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• v.50 no.6
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• pp.663-673
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• 2017

Heavy metal(loid) contamination of rice is the main issue in abandoned metal mine area with regard to food safety. A field study was conducted in mine area to see if soil amendments treatment including calcium superphosphate, sulfur, steel slag and S-containing fertilizer could reduce As and/or Cd content in rice grain and increase the growth of rice. The As content in brown rice reduced to 60% compared to the control only in $7.0Mg\;ha^{-1}$ of steel slag treatment. Cd reduction in rice was thought to be not the effect of amendments but the result from the difference in growth and development of rice plant and this could be ascribed to low soil Cd availability to rice plant. Compared with control, increased rice yield of cultivar Hwanggeumnuri was 1.3~2.2 and $1.5Mg\;ha^{-1}$ in calcium super phosphate and S-containing fertilizer treatment, respectively and the trend was also observed in cultivar Ungwang. However, steel slag treatment reduced the Ungwang yield by $0.4{\sim}0.9Mg\;ha^{-1}$. Future work will be needed to establish the agricultural measure with which secure the safety and yield of rice simultaneously.

• Journal of the Korean Dietetic Association
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• v.28 no.1
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• pp.19-29
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• 2022

This study examined the impact of perceived volume on satiety using 400 g kimchi fried rice in a normal rice bowl (Normal-400), 300 g kimchi fried rice in an augmented rice bowl with an elevated bottom (Illusion-300 and 300 g kimchi fried rice in a normal rice bowl (Normal-300). Thirty-six healthy women took part in this study once a week for three weeks. The Normal-400 (1st week), Illusion-300 (2nd week), and Normal-300 (3rd week) bowls were used to served kimchi fried rice to the same participants over three consecutive weeks. After each lunch, the consumption volume of fried rice, perception volume, and satiety rate were measured. The consumption volume of the fried rice was 313.8 g with the Normal-400, 248.9 g with the Illusion-300 and 240.2 g with the Normal-300. The perceived volume on an estimated five-point scale was 4.0 with the Normal-400, 4.1 with the Illusion-300 and 2.4 with the Normal-300. We compared the post-meal satiety of perceptually equal but quantitatively different amounts of food served in two different bowls (Normal-400 vs Illusion-300) and found that the participants felt equally full with both bowls despite having consumed significantly more food from the Normal-400. We also compared the post-meal satiety of perceptually different but quantitatively equal amounts of food in two different bowls (Illusion-300 vs Normal-300) and discovered that the subjects felt significantly fuller with the Illusion-300 although similar amounts of food were consumed from the two bowls. These two comparisons showed that visual cues play a critical role in determining satiety and that perceived volume is perhaps more important than the actual volume of consumed food, while in determining the level of fullness.

• Korean Journal of Food Science and Technology
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• v.25 no.1
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• pp.86-87
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• 1993

The steeping of waxy rice in water at $20^{\circ}C$ for 12 hr resulted in the decrease of protein, crude fat and ash contents. Water-binding capacity and swelling power (at $80^{\circ}C$) of waxy rice flour increased upon steeping. Maximum viscosity of waxy rice flour in 0.19 N sodium hydroxide solution was increased up to 6 hr steeping and decreased thereafter. The amylograph indices increased as the steeping time increased. The degree of changes in properties during steeping was different between two waxy rice cultivars.

• Korean Journal of Community Nutrition
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• v.14 no.5
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• pp.545-555
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• 2009

School foodservice customers are likely to be tired of repeated cycle menus and their satisfaction for meals offered in school is inclined to be low. The menu variety is an important factor in increasing customer satisfaction. The purpose of this study was to investigate customer perspectives for applying rice based bread menus in order to add menu variety and promote using rice processed products in school foodservice. The questionnaire was distributed to 760 parent samples in elementary schools and 520 student samples in middle/high schools and a total of 665 and 387 usable data were collected, respectively. Food habits such as preference for cooking method, menu preference, food allergy and nutritional perspectives for menu and customer perception for rice based bread like quality, reliability, price, and purchasing convenience were investigated using 7 Likert scale. Also expected menu types applying rice based bread and offering frequency of rice bread menu were examined. Preference level for bread-based meals were moderate and students' preferences were slightly higher than parents. Menu types applying rice bread expected by middle/high school students were western food (49.4%), spaghetti (28.4%), set menu (13.7%), noodle (17.6%), Korean food (11.1%), Chinese food (10.9%) and porridge (4.5%). The most occupied rate was once in a week for expected offering frequency. Most respondents perceived that rice bread was more nutritive and qualitative than the wheat based one.

• Food Science and Preservation
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• v.31 no.4
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• pp.507-517
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• 2024

This research aimed to investigate the changes in physicochemical properties and sensory qualities of cooked glutinous rice (RD6) by using the electric rice cooker method with different soaking conditions compared to cooking glutinous rice by steaming in a conventional steamer (control). Glutinous rice grain was soaked at different soaking conditions of temperatures at 25 and 45℃ and soaking time for 30, 60, and 90 min, and then were cooked by the electric rice cooker. The results indicated that the degree of starch gelatinization was increasingly correlated with the moisture content and water activity of the cooked waxy rice. Moreover, with the increase in the degree of gelatinization, the hardness value exhibited a decreasing trend, and the adhesiveness value increased. The L^* (lightness), a^* (redness), and whiteness index of cooked glutinous rice increased when the temperature and time of soaking increased, while the color intensity decreased. The overall acceptability scores indicated that the lower soaking time obtained a higher score for cooked glutinous rice. Compared with the control sample, the soaking conditions for the temperature and time of 25℃/30 min or 45℃/30 min are viewed as a suitable ratio of a good quality product for cooked glutinous rice by using the electric rice cooker method, in which rice cooking provided the high score of overall acceptability on consumer preference.

• Korean journal of food and cookery science
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• v.27 no.6
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• pp.735-743
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• 2011

This study examined physicochemical properties of rice grains and qualities of cooked white rice of the high yielding, Japonica type, specifically Druryechanbyeo and Boramchanbyeo, and of the Tongil-type, specifically Hanarumbyeo and Andabyeo. The changes of water absorption rate of rice grains, their textural properties and a sensory evaluation of the cooked rice s were analyzed. All varieties were short grain. The length and width of Tongil type rice grains larger than those of Japonica type. The water absorption of white rice grains increased rapidly until 1 hr when soaking and after that increased slightly. The water absorption of Druryechan grain was higher than that of the Boramchan. The sensory evaluation results showed that the Japonica type cooked rices had a higher value for overall quality than the Tongil type cooked rices. With regard to the textural properties of the cooked rices, the hardness of Boramchan and Hanarum varieties showed higher than that of Druyechan and Anda varieties. Adhesiveness, springiness and chewiness were not significantly different between varieties (p<0.05).