• Journal of the East Asian Society of Dietary Life
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• v.16 no.6
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• pp.677-683
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• 2006

Glutinous rice cake(Chalduk) was made by varying the hours of soaking time of glutinous rice in the water(0, 4, 8, 12, 24 hours). After storage for various periods, the sensory and physical characteristics and the degree of gelatinization were examined in order to determine the effect of glutinous rice soaking period on the quality of Chalduk. The results of the study are summarized as follows. In the sensory test, 8-hour water soaking produced the significantly highest score for salty taste, while 0-hour water soaking had the lowest score. Four-hour water soaking had the significantly highest score for the degree of chewiness. Eight-hour water soaking had the significantly highest score for overall desirability. For the moisture content of Chalduk covered with bean flour, 8-hour water soaking produced the highest moisture content but the difference was not significant. For the degree of gelatinization, 8-hour water soaking had the highest maltose content, which confirmed the suitability of 8-hour water soaking glutinous rice. Eight-hour water soaking had the lowest hardness. With increasing storage period, the hardness sharply increased. Elasticity was higher for the long-period immersed samples than for the non-immersed samples. In conclusion, an 8-hour soaking time for glutinous rice in water was proposed to maximize the Chalduk quality.

• Korean journal of food and cookery science
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• v.18 no.2
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• pp.211-215
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• 2002

This study was intended to investigate the optimal soaking time of glutinous rice for making jujube Injeolmi, a kind of traditional Korean glutinous rice cake. The jujube Injeolmi was prepared with glutinous rice soaked for various times (2, 4, 6, 8, 10 hr), and the moisture content, chromaticity, sensory qualities and mechanical qualities were measured while storing them up to 72 hr at 20$^{\circ}C$. The moisture content and L-value of jujube Injeolmi were the highest at 8-hr soaking. The a-value was the highest at 6-hr soaking. The hardness was maintained the lowest at the 8-hr soaked sample during storage. The cohesiveness and springiness were not significantly affected by the soaking time. The gumminess was significantly different among the samples during storage. The results of sensory evaluation showed that jujube Injeolmi had the best color at 4-hr soaking and the highest sweetness at 6-hr soaking. The 8-hr soaked glutinous rice gave the highest level of softness, chewiness and moistness in the sample, therefore, 8-hr soaking appeared to be the most desirable method for making jujube Ingeolmi.

• 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.

• Journal of the East Asian Society of Dietary Life
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• v.17 no.6
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• pp.883-893
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• 2007

To optimize the preparation process for oven-roasted glutinous rice cake, an experiment was derived using a central mixing composite design to determine the optimal conditions. The addition of flour by soaking time as well as sucrose and water, were the independent variables, with the moisture content, color, sensory, and texture properties of the ovenroasted glutinous rice cakes selected as response variables. For the moisture content, color, sensory, and textural properties, we found significant effects for moisture, lightness, redness, hardness, and cohesiveness in the oven-roasted glutinous rice cakes, and water was one of the most influential factors. The optimal mixing conditions for the highest quality oven-roasted glutinous rice cake, in terms of sensory and textural properties, were 266.0 g of water, 25.4 g of sucrose, and 61.5 minutes of soaking time for the glutinous rice flour. The soaking time was in close to the median, whereas the water and sucrose values were slightly above the median.

• Korean Journal of Food Science and Technology
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• v.17 no.6
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• pp.415-420
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• 1985

In this study, changes in physical and chemical properties of glutinous rice during various soaking periods (0, 0.08, 1, 3, 5, 7, 10 days) were investigated in order to clarify the relations ship between soaking period and expansion volume in the preparation of Gang Jung. The longer the soaking period was, the greater the expansion volume of Gang Jung was. Higher maximum viscosity and breakdown in amylogram of glutinous rice flour were observed as the soaking period was increased, As the length of soaking period increased, hardness of glutinous rice and size of flour particle significantly decreased, while sweeling power and solubility of glutinous rice flour showed no significant difference. Increased length of soaking period was associated with higher fatty acidity, higher acidity of water extract and lower pH of glutinous rice flour. Control of flour particle size distribution resulted in significantly larger expansion volume of Gang Jung. Brabender's amylogram showed that the increase of expansion volume of Gang Jung associated with the increase of soaking period was related to the change of rheological properties of glutinous rice. It seemed that changes in viscometric properties of glutinous rice was attributed to the different flour particle size distribution resulted from changes in hardness of rice during soaking.

• Korean Journal of Food Science and Technology
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• v.25 no.3
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• pp.247-251
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• 1993

Physico-chemical characteristics of glutinuous rice during soaking treatment at different temperature for Yu-Kwa (Korean traditional glutinous rice cake) processing were determined. Crude fat and protein contents of soaked glutinous rice decreased up to 30% to 50%, respectively, compared to raw rice, but there was a little difference in soaking periods. As the soaking period increased pH of soaking solution was decreased from 6.4 to 3.3, while Brix was increased from 0.5 to 13.6. Titration acidity of soaking solution and soaked rice were increased to 22.9 and 3.4, respectively, as the soaking period increased to 9 days at $20^{\circ}C$ soaking, but it was increased rapidly to 29.8 and 4.0, respectively, at $30^{\circ}C$. The three kinds of free sugar such as glucose, sucrose and maltose were detected. Glucose was the major produced free sugar during soaking, sucrose was not detected after 1 day soaking period. Characteristics of amylographic viscosity on soaked rice showed that there are no difference in pasting temperature by the soaking time and temperature, but the maximum viscosity was drastically increased on $1{\sim}2\;day$ soaking period and decreased rapidly after $2{\sim}3\;day$.

• Korean journal of food and cookery science
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• v.23 no.6
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• pp.908-918
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• 2007

To prepare ready-to-use rice flour as de novo material for processed rice foods, glutinous(W) and normal rice grains (N) were soaked for 1, 8, and 12 hours prior to processing. One half (DG) was air-dried and milled, and the other (WG) was milled and air-dried. General, morphological and pasting properties of the flours (NDG, NWG, WDG, WWG) were compared to those of a control (raw milled rice without soaking). The general compositions of the rice flours varied with soaking. Crude ash was considerably decreased at the beginning of soaking (1 hour). With the soaking, the rice flour, having polygonal shaped particles and a layered surface, acquired particles with smooth edges, which were then uniformly distributed. Additionally, the WG flour was lighter and had a lower ${\Delta}E$ value than the DG flour, due to a higher L and less +b as a result of soaking. Compared to the control, the WBC of the normal rice flour was decreased significantly with soaking, and the WG flour had significantly lower WBCs than the DG flour. Stirring number (SN), an indicator of ${\alpha}-amylase$ activity, was highly and significantly correlated with WBC (r=-0.85, p=0.0001) in the normal rice flour. At $80^{\circ}C$, the SP and solubility of all the soaked rice flours were much higher than those of the control. Positive (r=+0.85, p=0.0001) and negative (r=-0.61, p=0.02) correlations between the SP and solubility of the normal and glutinous rice flours were found, respectively. Using RVA, the pasting temperature of NDG was lower than that of NWG (p<0.0001). The peak viscosities of all the soaked flours were significantly decreased with soaking (p<0.0l), with the highest viscosity in the normal rice flour soaked for 8 hrs. Total setback, indicative of retrogradation, was lower in NDG than in NWG, with the lowest setback at 8 hrs of' soaking. Based on these finding, the NDG flour with 8 hrs of soaking was less damaged, and had a lower total setback and lower pasting temperature, which would make it an appropriate rice flour for commercial mass production.

• Korean Journal of Food Science and Technology
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• v.32 no.1
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• pp.69-74
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• 2000

Varietal difference in physicochemical characteristics of glutinous rice grain and interrelationships between these properties and the quality characteristics of Yukwa(fried rice cookie) were investigated on fourteen rice varieties, to obtained the basic informations for diversifying the utility of glutinous rice grain and for developing various glutinous rice cultivars adaptable to glutinous rice food processing. Among physicochemical properties of glutinous rice grain, the content of released reducing sugar during soaking treatment was the most positive correlation between the adaptability to Yukwa processing quality. CB243 and Sandong 71 were the most adaptable glutinous rice cultivars to make the Yukwa, because of its tested score in expansion volume, crispiness and sensory preference was higher than other glutinous rice cultivars.

• Food Science and Preservation
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• v.13 no.3
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• pp.344-350
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• 2006

Soaking and drying were studied for seven grains and legumes including glutinous rice, brown rice, glutinous brown rice, glutinous barley, Seoritae, Heuktae and red bean to improve taste of cooked mixed grams and make easy to cook then Seoritae and Heuktae showed the highest water absorption and the rest were in the order of glutinous barley, glutinous rice, milled rice, brown glutinous rice, brown rice, and red bean. In regards with water absorption index by soaking temperature, the higher the temperature showed, the more water absorption and the shorter time to reach the water absorption balance, the more grinding legumes. showed the more water absorption and the shorter time to reach to the water absorption balance. The soaked samples were dried at mom temperature $30^{\circ}\C,\;50^{\circ}\C$, and microwave 300 W, 700 W and 1000 W power. As a result 700 W drying method br microwave can dry samples in the shortest time without damage to the samples. Therefore, it was considered as the best pretreatment conditions for mixed stains to dry with 700 W microwave after one-hour soaking at $30^{\circ}C$.

• The Korean Journal of Community Living Science
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• v.23 no.4
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• pp.537-552
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• 2012

This study was conducted to investigate the quality characteristics of cooked rice with cereals frequently consumed in Korea by blending ratio. Seven kinds of cereals, white rice, glutinous barley, brown rice, black rice, glutinous rice, glutinous foxtail millet and proso millet, were chosen for the study. According to the results from rapid viscosity analyzer, glutinous barley had the lowest pasting temperature($66.55^{\circ}C$) and black rice had the highest values in the peak(231.77 RVU), trough(162.25 RVU), final viscosity(295.81 RVU) and set back(64.05 RVU)(p<0.05). Water absorption rate by soaking time for black rice and brown rice was increased only 18.77% and 14.57%, respectively, even after 120 minutes, whereas those of other cereals were increased up to 20.28~39.32% after 50 minutes. The pasting characteristics of white rice blended with cereals tended to be lower than white rice in the peak, trough, and final viscosity. Textural property of cooked white rice blended with black rice, brown rice, and glutinous foxtail millet showed a significantly higher value for hardness than that of cooked white rice only(p<0.05). The most preferred blending ratio of the respective cereals was 25% for glutinous barley, 10% for black rice, brown rice and proso millet, and 5% for glutinous foxtail millet and glutinous rice in the sensory evaluation for overall quality, but there were no significant differences except glutinous barley, brown rice and glutinous foxtail millet.