• Journal of the Korean Society of Food Science and Nutrition
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• v.34 no.9
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• pp.1434-1442
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• 2005

The Present study was attempted to investigate the Possibility of modification of functional properties of the rice flour by crosslinking proteins using microbial transglutaminase (mTGase) derived from a variant of Streptoverticillium sp. MTGase was added at various levels (3,000, 5,000, 7,000 and 10,000 ppm) during making noodles mixed with the rice flour. Mixograph and farinograph showed that imported wheat flour (IWF) had strong dough stability, while the rice flour showed very weak dough strength. However addition of mTGase (3,000, 5,000 and 7,000 ppm) resulted in improvement of dough stability of the rice flour. Texture profile analysis (TPA) results indicated that most of texture parameters (gumminess, chewiness and hardness) of cooked noodles prepared from the rice flour were significantly lower than those of noodles prepared from IWF. However, by addition of mTGase (at the levels of 3,000, 5,000, 7,000 ppm) dough stability and all the TPA values and sensory score (at the level of 7,000 ppm mTGase) on chewiness and hardness of cooked noodles made with $30\%$ rice flour were improved significantly. These results suggest that dough stability and texture of rice noodles as well as sensory characteristics could be improved by addition of mTGase to the rice flour.

• Korean Journal of Food Science and Technology
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• v.48 no.1
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• pp.92-95
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• 2016

Ultra-high pressure (UHP) was applied to glutinous rice (Dongjin) and brown rice (Shindongjin) to determine its effects on the textural characteristics of cooked rice and bacterial reduction in uncooked rice. Hardness and stickiness of the cooked glutinous and brown rice pretreated with 500 MPa for 5 min were significantly attenuated compared to that of the control rice (p<0.05). After the UHP treatment, particles of the glutinous and brown rice were observed to be finer when cross sections of the rice were analyzed using field emission scanning electron microscope. The total bacterial count in the brown rice treated with 600 MPa for 5 min was reduced from $10^7CFU/g$ to $10^4CFU/g$, while the number of thermoduric bacteria in the brown rice was not significantly different after the UHP treatment. These results suggest that UHP may be an effective method for improving texture of dried rice and to reduce bacterial count in raw rice.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.53 no.spc
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• pp.53-57
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• 2008

The experiment was carried out to select the rice cultivar adaptable to Top Rice cultivation region from 2006 to 2007 in Useong and Kyeongju, Korea. Four cultivars, recommended for high rice grain quality, were cultivated in the different region in this study. The average yield of head rice was higher in Samguangbyeo than the other three cultivars. The protein content was inversely associated with palatability (Toyo value). The protein content of Samguangbyeo was 6.2%, which was the lowest among the tested cultivars. L values in color of rice and cooked rice were not significantly different. The hardness of Samguangbyeo was lower than that of the other cultivars in texture properties of boiled rice on 4 cultivars. In conclusion,considering the rice yield and grain qualities, Samguangbyeo was selected as promising rice cultivar for Top Rice cultivation region.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.35 no.1
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• pp.34-43
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• 1990

Six commerical rice varieties were cultivated and harvested at different locations in 1987 and 1988 to clarify the degree of locational variations. of several characteristics related to rice grain quality using the rice samples harvested from 8 to 20 locations for a variety each year. Locational variations of percent brown rice, percent milled rice, 1000-grain weight and amylose content were small, but whole grain rate, alkali digestibility, gel consistency, percent white-center and white-belly grain, degree of chalkiness and degree of translucency showed larger variations between locations. The degree of locational variation of sensory evaluation score for eating quality of cooked rice were varied from small to large along with rice variety used and year cultivated. Texture palatability index and stickiness of cooked rice among rheogram characteristics showed larger locational variations, but cohesiveness and springiness showed smaller variations between locations. Set back, break down and maximum viscosity showed larger locational variations among amylogram characteristics of rice flour. Special attention was given to a cultivated location, Anseong, because rice samples harvested at Anseong showed lower percent white-center and white-belly grain, and low set back and high break down in Chucheongbyeo, lower percent white-center and white-belly grain, higher texture palatability index and viscousness/hardness ratio, and low set back and high break down in Dongjinbyeo, higher texture palatability index, and low set back and high break down in Yongmunbyeo, lower percent white-center and white-belly grain in Sangpungbyeo, and low set back and high break down in Samkangbyeo. No other locations in this study produced rice samples showing wide acceptable quality-related characteristics except Anseong.

• Korean journal of food and cookery science
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• v.32 no.4
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• pp.449-457
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• 2016

Purpose: The study was conducted to analyze the change in quality characteristics of Ddukguk Garaedduk and Ddukgukdduk by the frequency of extruding rice dough. Methods: Ddukguk Garaedduk samples were made by extruding and shaping rice flour dough 2, 3, and 4 times; while Ddukgukdduk samples were made by drying the Ddukguk Garaedduk at room temperature for 48 hours and slicing them in slices of 0.3 cm thickness. Results: Significant differences were not found in water content by the extrusion frequency for Ddukguk Garaedduk and Ddukgukdduk. The adhesiveness and springiness of Ddukguk Garaedduk with a 4 times extrusion were significantly higher than those of Ddukguk Garaedduk with a 2 times extrusion. Ddukgukdduk with a 4 times extrusion generated finer cells and a more even distribution of cells than the other samples, as observed by scanning electron microscopy. Upon boiling, significantly more water was absorbed in Ddukgukdduk of a 2 times extrusion than in that of a 4 times extrusion. Hardness and adhesiveness scores of the cooked Ddukgukdduk were the highest, and springiness was the lowest in the sample with the 4 times extrusion. Conclusion: The extrusion of rice dough makes the structure of Ddukguk Garaedduk finer and more even, which results in the increased adhesiveness of Ddukguk Garaedduk. When cooking Ddukguk, Ddukgukdduk that has been extruded more absorbs less water and dissolves less solids, which maintains the chewiness and structure of cooked Ddukgukdduk.

• Journal of the Korean Society of Food Science and Nutrition
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• v.43 no.8
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• pp.1264-1269
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• 2014

This study investigated the effects of rice starch addition, including native, acetylated, and hydroxypropy-lated rice starch, on the quality characteristics of instant fried noodles. Compared to 100% wheat flour (control), flours containing acetylated or hydroxypropylated rice starch showed reduced initial pasting temperatures as well as peak and breakdown viscosities as determined using a Rapid Visco-Analyzer (RVA). The addition of acetylated and hydroxylated rice starch as well as native rice starch increased cooked weight, volume, and water absorption of the fried noodles compared to control noodles. The addition of native rice starch tended to increase softness of noodles, whereas addition of acetylated or hydroxypropylated rice starch significantly lowered hardness, gumminess, and chewiness values. The results of the sensory evaluation indicate that noodles containing rice starch showed improved sensory characteristics such as color, appearance, flavor, taste, and texture. Especially, acetylated rice starch could be used to improve eating quality of instant fried noodles.

• Journal of the Korean Society of Food Science and Nutrition
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• v.42 no.11
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• pp.1878-1885
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• 2013

The purposes of this study are to generate sensory profile, measure consumer acceptance, and determine liking and disliking factors of aseptic-packaged rice porridges (APRP). Five APRPs made by five different rice cultivars were used for this study. Twenty-one attributes were generated by trained panelists. Finally, 16 attributes were determined as descriptive terms for APRP. Each cultivar showed a different descriptive sensory profile. In a consumer acceptance test, there was no statistical difference (P>0.05) in the acceptances of the overall, appearance, taste, texture, viscosity, and rice particle texture among the 5 APRPs. SW52 showed the highest acceptance ratings in the overall, appearance, taste and texture, followed by SR. A total of 52% of consumers showed preference toward SW52 and SR. SW63 showed the lowest ratings and no consumer preference pattern. Consumers were divided into two groups by a cluster analysis; one was the consumers (C1) who liked APRP, and the other was the consumers (C2) who had a neutral stand in general. By correlating the results from descriptive analysis and consumer ratings from C1, liking and disliking factors for consumer acceptance were determined. The disliking factors were bitterness, feeling of surface, stickiness, metallic flavor, roasted aroma, and thickness. The liking factors were old cooked rice aroma/flavor. The disliking factors dominated in the determination of acceptability of APRP. Selecting rice cultivars that had low intensities of disliking factors is the key for APRP development.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.33 no.s01
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• pp.1-17
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• 1988

Rice Quality is considered to the five catagories ; the nutritional value: the characteristics of cooking. eating and processing: grain size, shape and appearance : milling yields: and storage characteristics. Because most rice is processed and consumed in whole-kernel form. the cooking and eating quality is of important and the physical properties of the intact kernel such as size, shape and general appearance are of particular significance in determining marketing quality. Eating Quality which can be directly evaluated by consumer's panel test is so complicate and variable, and thus the objective and simplified method of evaluation is required of using appropriate instruments. Even though many researches have been done to evaluate the eating quality in various aspects such as the texture of cooked rice kernels, amylogram analysis of rice powder, amylose content. gelatinization temperature. moisture absorption of rice kernel, and cooking characteristics, none of them is satisfied for the evaluation of eating quality. The improving eating quality should be also considered to many cultural factors. such as varieties, climatic and soil conditions, cultural method, handling after harvest. milling and storage conditions. In Korea, many researches in grain size. shape and appearance, and eating quality have been done with the varietal improvement mainly by rice breeders, but no effective method of evaluation was established. A few research have been done in the relationship between rice quality and cultural factors. In the future, research in rice quality should emphasize to establish the standard evaluation method in the physicochemical properties of rice kernels for application of varietal selection. and to develop cultural practices for the preserving quality characteristics of the varieties.

• Culinary science and hospitality research
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• v.16 no.4
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• pp.286-296
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• 2010

The purpose of this study is to develop fresh pasta added with mulberry leaf powder as functional fresh pasta. Through previous research, the mixture of 40% of flour and 60% of rice powder was optimum for making noodles with mulberry leaf powder. Making fresh pasta with 40% of wheat flour, 60% of rice powder (optimum moo for making noodles) and mulberry leaf powder(0.5% 1.0% 1.5% 2.0%) was done, followed by the mechanical test(moisture content, color value, texture, tension) and the sensory analysis(quantitative descriptive analysis, preference test). Moisture contents of raw pasta and cooked pasta were the highest in control; scores for moisture contents of cooked pasta were higher than those of raw pasta. The result indicated that the more mulberry leaf powder was, the lower L-value and a-value were in raw pasta and cooked pasta. While the b-vale(yellowness) of raw pasta was the highest in control(9.81), 1.0% of mulberry powder addition sample was the highest in cooked pasta. For hardness, the 2.0% of mulberry leaf powder addition sample has high scores, and adhesiveness and chewiness were no significant difference. The 0.5% of mulberry leaf powder addition sample was the longest in tension distance, which was resulted from the lack of water contents in mulberry leaf powder. In cooked pasta, tension distance had no significant difference between the samples, and force showed the highest score in control. The quantitative descriptive analysis showed that color intensity, savory taste, bitterness were the highest in the 2.0% of mulberry leaf powder addition sample. Gloss and chewiness were no significant difference between the samples. Grassy flavor, savory flavor, bitterness and grainess were intense as mulberry leaf powder was added The preference test showed that MRP 1.5 containing 1.5% of mulberry leaf powder was the most preferable for color, texture and overall quality. In conclusion, 40% of wheat flour, 60% of rice powder and 1.5% of mulberry leaf powder made the best formula of fresh pasta with mulberry leaves.

• Korean journal of food and cookery science
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• v.9 no.3
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• pp.187-194
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• 1993

Effects of the steaming conditions on textural and sensory quality of rice cakes were investigated with respect to storage period. All steaming methods except microwave oven cooking were not remarkably decreased in moisture content during storage. Degree of gelatinization was shown much higher in the both of rice cakes prepared by the rice-cake steamer and steaming pot than those of microwave oven cooking sample. Effect of the different steaming conditions on the rice cake quality resulted that the sensory profiles (consistency, moistness and cohesiveness) were apparently improved in the cakes prepared with rice-cake steamer and steaming pot cooking than microwave oven cooking. The highest overall quality was shown in the samples cooked by rice-cake steamer. The rice cakes prepared by microwave oven showed the highest hardness and chewiness in the textural profiles, whereas the rice cakes prepared by the rice-cake steamer and the steaming pot showed the high gumminess.