• Journal of the Korean Home Economics Association
• /
• v.23 no.3
• /
• pp.55-61
• /
• 1985

This study was designed to find out the optimum processing condition and the characteristics of yeots : In this study, Yeoteses were made from glutinous rice, Rice, Millet, Sorghum and Corn by microwave oven. The textural parameters of various Yeotses were determined by sensory evaluation and Rheometermeasurement. RESULTS : 1. The sweetness of all the raw materials before saccharification is 11%. In case of the sweetness of the raw materials after saccharification, Glutinous rice was the highest(28.8%) and Corn was the lowest(17.7%). Also, the sweetness of Glutionous rice Yeots was the highest(86%) and Corn Yeots was the lowest(82.7%).It showed similar tendancy to the sensory evaluation for sweetness. 2. The pH of the raw materials before saccharification was 4.4.The pH of sorgphum after-saccharification was the highest (4.7) and that of Corn was the lowest (4.3). 3. In the sensory evaluation of the various Yeotses, Glutinous rice Yeots showed the best quality and it did not showed any significant difference between glutinous Yeots and Rice Yeots.The overalll quality of Milet, Sorghum and Corn Yeotses were inferior to Glutnous and Rice Yeotses. Textural characteristics by Rheometermeasurement revealed differences among the various Yeotses. Hardness, Cohesiveness, Adhesiveness were the highest in Glutinous rice and Rice Yeotses. Adhesiveness showed similar tendancy to that of the sensory evaluation. 4. However, Becuase glutinous rice is more expensive than rice, it is desirable that we use Rice Yeots.

• Korean Journal of Food Science and Technology
• /
• v.41 no.3
• /
• pp.296-301
• /
• 2009

In order to investigate the effect of different yeasts (La Parisienne (LP), Y18-2, Y54-3, Y90-2, Y90-9 and Y272-7) from nuruks on the quality of Glutinous rice wines, physicochemical properties and volatile flavor components were evaluated. Glutinous rice wines prepared with different yeasts were analyzed for ethanol, pH, total acid, amino acid, soluble solid, coloring degree, UV absorbance, reducing sugar, organic acid, free sugar and volatile compounds. After fermentation for 17 days, the ethanol contents ranged from 13.40 to 14.50%, while the total acid levels were from 0.33 to 0.44%. The amino acid contents in six samples ranged from 0.13 to 0.18%, while soluble solid contents ranged from 12.1 to $14.7^{\circ}Bx$. The glutinous rice wine prepared with LP showed the highest level of coloring degree, soluble solid and reducing sugar among six samples. Organic acid contents of the glutinous rice wine prepared with LP had the highest levels of lactic acid and acetic acid, while the glutinous rice wine prepared with Y90-9 had the highest level of succinic acid. In all glutinous rice wines tested, the most abundant free sugars were glucose followed by maltose. Volatile flavor components in the glutinous rice wines were identified by using GC-MSD. Nineteen esters, ten alcohols, eight acids, one aldehyde and one miscellaneous compound were identified in the glutinous rice wines. Using relative peak area, it was found that other than ethyl alcohol, hexadecanoic acid ethyl ester was the major component, predominantly found in the range of 2.73-10.41%. Phenylethyl alcohol, isoamyl alcohol, ethyl oleate, ethyl linoleate and tetradecanoic acid ethyl ester were some of the major volatile components present through the fermentation, respectively. Overall, it was shown that different yeast strains from nuruks greatly affected chemical and volatile characteristics of the glutinous rice wines.

• Korean journal of food and cookery science
• /
• v.2 no.2
• /
• pp.43-54
• /
• 1986

Back-pyun is a kind of rice cake made by steaming rice flour added sugar, water and salt and garnished with shredded chestnuts, dates, mushrooms and pinenuts. The Back-pyun has been widely used in Korean celebrations. This study aimed to compare and determine the effects on sensory characteristics and texture of Back-pyun 1) when the proportion of glutinous rice, added i.1 making Back-pyun, is 0%, 5%, 10%, 15%, 20%, 25% and 30% 2) then it reheated after storage for 0,24, 48 and 72 hours. Evaluation was conducted through sensory evaluation and objective evaluation. The results are as follows : 1. In sensory evaluation, color of Back-pyun turned yellow as the addition level of glutinous rice increased and then by reheating after storage for 24, 48 and 73 hours. Coarseness was not significantly different as the addition level of glutinous rice increased before storage. But Back-pyun reheated after storage for 24,48 and 72 hours were significantly different by the addition level of glutinous rice. Softness, dryness and crumblyness tended to decrease as the addition level of glutinous rice increased and by reheating after storage for 24, 48 and 72 hours. The most favorite tendency on the appearance was at the addition level of glutinous rice of 5%. Texture and overall preference were better at the addition level from 10% to 20% than any other levels. 2. Rheometer measurement indicated that compression force, gumminess ana chewiness tended to increase as the addition level of glutinous rice increased and decrease by the storage conditions. But work ratio and recovered height did not have much effect the addition level of glutinous rice and the storage conditions. Compression force of Back-pyun (not reheated) tended to increase by the storage time and the addition level of glutious rice. Especially it showed remakably increasing tendency during 24 hours storage (at $4^{\circ}C$) 3. Moisture content tended to increase by the addition level of glutinous rice and decrease by the storage time. But moisture content of Back-pyun reheated after storage for 24 hours stowed the increasing tendency. 4. Softness of Back-pyun had significant relationship with compression force and work ratio. Dryness and crumblyness had significant relationship with work ratio. Therefore compression force and work ratio represented the texture of Back-pyun.

• Journal of the Korean Society of Food Science and Nutrition
• /
• v.41 no.6
• /
• pp.846-852
• /
• 2012

The physical properties of instant puffed rice snacks with non-glutinous, glutinous, and steamed non-glutinous rice were evaluated at different moisture content and puffing temperatures. Raw materials were tempered to 9%, 12%, 15%, and 18% moisture content and puffed at $200^{\circ}C$, $210^{\circ}C$ and $220^{\circ}C$. With the increase in moisture content and puffing temperature, puffed snacks were less bulky. As the moisture content decreased and puffing temperature increased, the whiteness (L) value of puffed snacks decreased, while the redness (a) and yellowness (b) values increased. WSI and WAI were higher with an increase in moisture content and puffing temperature. Instant puffed rice snacks made from non-glutinous, glutinous, and steamed non-glutinous rice showed differences in bulk density, WSI, and WAI, while no difference was found in color values. When the moisture content increased from 9% to 15%, the cells within the products became more uniform and smaller. The instant puffed rice snacks made from glutinous rice showed the smallest and most uniform cell structure.

• Korean Journal of Food Science and Technology
• /
• v.17 no.6
• /
• pp.415-420
• /
• 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
• /
• v.40 no.5
• /
• pp.551-557
• /
• 2008

In order to investigate the effect of different ingredients on the quality of Korean rice wines, 30% of rice were substituted by malt, corn, potato, soybean, glutinous millet, unpolished rice, glutinous rice, or non-glutinous rice, when rice wines were prepared. Physicochemical and sensory characteristics of the rice wines from the varying ingredients were evaluated. Sample rice wines were analyzed for ethanol, pH, total acid, amino acid, soluble solid, coloring degree, UV absorbance, reducing sugar, organic acids, and free sugars. After fermentation for 16 days, the ethanol contents ranged from 13.28 to 16.23%, while the total acid levels were within the range of 0.27 to 0.32%. The amino acid contents in eight samples ranged from 0.18 to 0.36%, while the soluble solid contents were within the range of 8.35 to $11.1^{\circ}$Bx. Among the eight samples tested, rice wine prepared with malt showed the highest level of coloring degree, UV absorbance, and reducing sugar levels, while rice wine prepared with potato showed the lowest value. Organic acid contents of rice wines prepared with soybean, glutinous rice, and non-glutinous rice showed the highest levels of succinic acid followed by acetic acid, citric acid, malic acid, and pyroglutamic acid. Free sugar contents of all rice wines showed the higher levels of glucose followed by fructose and maltose. Rice wines prepared with unpolished rice and corn showed the same highest overall sensory preference. By descriptive analysis, the overall mean sensory intensities of samples prepared with glutinous rice and non-glutinous rice, showed similar levels of 'sweetness', 'fruitiness', and 'freshness of aroma', while those samples prepared with soybean, glutinous millet, and potato showed stronger intensities of 'nuruk', 'grain aroma', and 'yellowness'. Rice wine prepared with corn showed middle ranges in all sensory attributes tested.

• The Korean Journal of Food And Nutrition
• /
• v.27 no.2
• /
• pp.294-301
• /
• 2014

Rice (Oryza sativa L.) is one of the most important staple foods in Korea and the consumption of brown rice is increasing annually. The objective of this study is to investigate the physicochemical, hydration and textural properties related to eating quality of cooked brown rice by using glutinous, semi-glutinous, four non-glutinous and four colored varieties. The moisture, protein and total dietary fiber contents of brown rice are shown in the range of 11.1~12.6%, 6.6~8.7% and 6.28~12.40%, respectively. The amount of water uptakes for brown rice during the hydration has shown significant differences. The glutinous variety of Boseogchal indicate the highest water absorption levels by reaching $0.38gH_2O/g$. The hardness of hydration for Seolgaeng is distinctively lower than those of the other brown rice varieties. According to the textural characteristics of cooked brown rice when using the Tensipresser, the hardness of Boseogchal, Baegjinju and Seolgaeng all exhibit the lowest values out of ten varieties and the highest levels of adhesiveness.

• Food Science of Animal Resources
• /
• v.33 no.5
• /
• pp.572-580
• /
• 2013

This study was carried out to evaluate the effect on properties of restructured jerky by the addition volume of additives. The treatments were divided into glutinous rice flour, potato starch, soybean and acorn powder. Moisture content, water activity ($a_w$), thiobarbituric acid reactive substances (TBARS), color, yield and sensory evaluation were performed. The moisture contents of four types of restructured jerkies were in the range of 8.92-12.47%, and were lower than that of the control (17.92%). Water activity tended to decreased with increasing addition of all treatments. The restructured jerkies containing glutinous rice flour, potato starch, soybean and acorn powder had lower TBARS than the control. The drying yield tended to increase with increasing amount of additives. In the sensory evaluation results, the highest overall acceptability was found in jerky containing glutinous rice flour, potato starch, and acorn powder when the addition was 9%, while that for soybean powder was determined to be 5%. These results suggest that 9% additions of glutinous rice flour, potato starch or acorn, or 5% soybean powder are optimal addition volumes for the preparation of restructured jerkies.

• Korean Journal of Food Science and Technology
• /
• v.42 no.1
• /
• pp.75-81
• /
• 2010

In order to investigate the effects of different milling degrees on the quality of glutinous rice wines, the physicochemical properties and volatile compounds of various wines were evaluated. Sample wines prepared from glutinous rice with 90, 80, and 70% milling yields were analyzed for ethanol, pH, total acids, amino acids, soluble solids, coloring degree, UV absorbance, reducing sugars, organic acids, free sugars and volatile compounds. After fermentation for 17 days, ethanol contents in the wines ranged from 15.2 to 15.85%, while total acid levels ranged from 0.31 to 0.35%. The amino acid contents in four samples ranged from 0.63 to 0.73%, while soluble solid contents ranged from 11.4 to $13.1^{\circ}Bx$. The wine prepared from glutinous rice with a 30% degree of milling showed the highest coloring degree, UV absorbance and reducing sugar content among four samples. Furthermore, this wine had the highest levels of malic acid and acetic acid, while the glutinous rice wine prepared from rice with a 0% degree of milling had the highest levels of succinic acid and lactic acid. In all the glutinous rice wines tested, the most abundant free sugar was glucose followed by maltose. With increasing degree of milling, the alcohol, amino acid and organic acid contents of the glutinous rice wines decreased, whereas soluble solids, coloring degree, UV absorbance, reducing sugar and free sugar contents increased. Volatile compounds were identified using GC-MSD, and thirty-nine esters, seven alcohols, six acids, one aldehyde, four alkanes, one alkene and two miscellaneous compounds were identified in the glutinous rice wines. Using relative peak area, it was determined that other than ethyl alcohol, hexadecanoic acid ethyl ester was the major component and was primarily found in the range of 11.566-18.437%. Succinic acid diethyl ester and isoamyl laurate decreased with an increasing degree of milling, whereas hexanoic acid ethyl ester and 2-octenoic acid ethyl ester increased. Overall, it was shown that different milling degrees greatly affected the physicochemical and volatile characteristics of the glutinous rice wines.

• Journal of the East Asian Society of Dietary Life
• /
• v.16 no.3
• /
• pp.323-331
• /
• 2006

The manufacture and consumption of traditional Korean rice cake is being revived due to the introduction of various desserts and confectionaries in the food industry. In order to develop this traditional food of Korea and allow various types of rice cakes to enter the market, it is essential to standardize the cooking methodology. In particular, there has been little research on Dutubpyun, a traditional food famous for its good taste. In addition, the original cooking methodology varies between cookbooks. Therefore, in order to standardize the cooking methodology for Dutubpyun referring to various cookbooks, different types Dutubpyun were made by varying the grain fineness of the glutinous rice powder to 16, 20, 30 and 40 meshes, adding up water to 10%, up sugar to 10% and up soy sauce to 5%. Subsequently, a sensory evaluation, and a test on the moisture, degree of gelatinization and hardness during storage were measured to determine the optimal grain fineness of the powder. For the sensory evaluation, where the grain sizes of the glutinous rice powder were different, the 30 and 40 mesh samples received high scores for grain fineness, moisture and chewiness. The 40 mesh samples received high scores for softness, while the overall quality was the highest in the 30 mesh samples. The moisture content during storage was $38.0{\sim}40.6%$ for the samples on the day of cooking, while it was reduced to $33.3{\sim}35%$ after 3 days of storage. Regarding the degree of gelatinization during storage, the maltose content was $2.4{\sim}2.7 mg$ for the samples on the day of cooking. After 3 days, the maltose content was $2.3{\sim}2.8 mg$ but the maltose content was higher in the 40 mesh samples than in the other samples. Regarding the change in hardness during storage, the hardness marked high in the 20 mesh samples on the day of cooking (p<0.05), while it was high in the 16 mesh samples after 3 days of storage (p<0.001). The hardness tended to increase with increasing storage time. Regarding the surface structure of the glutinous rice powder and Dutubpyun, a difference in grain fineness was clearly seen in the 15x-magnifications photograph of the rice powder structure taken by SEM. At 60x and 180x magnifications of surface of Dutubpyun, the 16 mesh samples had a uniform air gap, and a lumpy configuration. Smaller air gaps were dispersed homogeneously and similar to a net in the 20 and 30 mesh samples. The 40 mesh samples showed to a net-likes structure with cracks. Overall, for the best conditions for cooking Dutubpyun, the grain fineness of the glutinous rice power needs to be 30 mesh.