• Korean journal of food and cookery science
• /
• v.9 no.3
• /
• pp.210-214
• /
• 1993

This investigation was undertaken for the purpose of studying the physicochemical properties of rice flour made by various soaking time(1,4,6,8,12 hours) of rice. As the soaking time was longer, the lightness of rice flours increased, on the contrary its redness and yellowness decreased. Rice flours had higher swelling power and solubility by increasing soaking time, but water binding capacity decreased upon soaking of rice. Hot water insoluble amylose of rice flours was decreased, whereas hot water soluble amylose was increased as the soaking time increased. The amylograph indices indicated that initial pasting temperature of rice flours decreased, while maximum viscosity increased as the soaking time increased.

• Korean Journal of Rural Living Science
• /
• v.8 no.2
• /
• pp.125-129
• /
• 1997

The effect of mugwort powder on some physicochemical properties of rice flour, the viscosity of rice flour pastes and the degree of gelatinization of pastes and gels were investigated. By addition of mugwort, water binding capacity, swelling power, and solubility of rice flour were increased, also the viscosity and, the degree of gelatinization of rice flour pastes and gels were increased. Generally wet rice flour-mugwort pastes and gels were better than those of dry rice flour-mugwort. And viscosity and gelatinization of the rice-mugwort pastes and gels were decreased slightly during storage at $20^{\circ}C$ for 7 days.

• Food Science and Preservation
• /
• v.17 no.2
• /
• pp.208-213
• /
• 2010

We sought to optimize parboiled rice preparations with respect to nutritional composition and to compare the physicochemical properties of polished, glutinous rices and Olbyossal (parboiled rice). Crude lipid contents (all w/w) were: brown glutinous rice (1.92%) > Olbyossal (1.13%) > glutinous rice (1.08%) > polished rice (0.32%). The crude ash content of Olbyossal was greater than that of polished rice. There was no significant difference in crude protein level between Olbyossal and polished rice. Total dietary fiber content (all figures are w/w) was higher in Olbyossal (3.79%) than in polished rice (1.67%). With respect to mineral content, P (249.16 mg%), K (144.67 mg%), Na (35.41 mg%), and Mg (30.24 mg%) levels were higher in Olbyossal than in polished rice. There was no significant difference in fatty acid or amino acid content between polished rice and Olbyossal. The L value (lightness) of Olbyossal was lower than that of polished rice but the hardness of Olbyossal was greater.

• Journal of the Korean Society of Food Science and Nutrition
• /
• v.39 no.2
• /
• pp.274-280
• /
• 2010

This study was to investigate the quality characteristics of noodles prepared with germinated brown rice and rice bran, and to determine the changes in GABA content and antioxidant activity of the noodles. These noodles were evaluated for cooking properties (cooking loss, swelling index, water holding capacity), total polyphenols, antioxidant activities (radical scavenging of ABTS and DPPH), and GABA contents. The addition of germinated rice bran in the range of 5, 10, and 15% showed a significant influence on cooking loss, although no effect on swelling index was observed. The raw and cooked noodles containing germinated brown rice and rice bran contained more GABA contents (2751.6~4176.7 and 5522.0~9617.8 nmol/20 g of fresh noodle, respectively) than those of non-germinated brown rice and rice bran. Noodles made with germinated brown rice and rice bran had similar total polyphenolics contents and antioxidant activities compared to noodles made with non-germinated brown rice and rice bran. Overall, the germinated brown rice could be used as a good ingredient to increase the nutritional value and antioxidant properties of wheat flour noodle without affecting the cooking properties.

• Korean journal of food and cookery science
• /
• v.28 no.6
• /
• pp.813-820
• /
• 2012

To develop the high quality gluten-free rice products with health functionality and desirable texture with moistness, the physicochemical properties of extruded rice flours prepared from the mixture of germinated brown and white rices were investigated. The domestic organic Samgwangbyeo was used to make white and germinated brown rices. White rice (WR) was dried after soaked for 6 h at $15{\pm}3^{\circ}C$ and mixed with germinated brown rice (GBR) with different mixing ratios (100:0, 75:25, 50:50, 25:75, 0:100). The operating conditions of twin screw extruder were 250 rpm of screw speed, $120^{\circ}C$ of barrel temperature, and 25% moisture content of rice flour. The ash, crude protein and crude lipid contents were significantly different (p<0.05) and those of extruded GBR were the highest values, but those of extruded WR were the lowest. The color difference of extruded WR based on white plate showed the lowest among them. The water binding capacity (334.16%), swelling power (8.83 g/g), solubility (33.13%), and total starch (79.50%) were the lowest in extruded GBR. The viscosities of all extruded rice flours by RVA were maintained during heating. The peak and total setback viscosities of extruded rice flours ranged 127-352 and 58.0-85.5 cP, respectively. The novel food biomaterial from germinated brown rice as well as white rice was developed by twin screw extruder. The extruded rice flours control the moistness to improve the texture and also have functional materials, dietary fiber, GABA, and ferulic acid, etc to increase quality of gluten free rice products.

• Journal of the Korean Society of Food Science and Nutrition
• /
• v.34 no.7
• /
• pp.1098-1102
• /
• 2005

Properties of rice flours prepared from milled and broken rice produced by pre-washing and subsequent drying process were investigated. Compared to untreated ordinary milled rice, pre-washing process slightly increased lightness of rice flour, while decreased yellowness. Both WAI and WSI were higher in the flour from pre-washed rice, and gel consistency was the highest in the flour from pre-washed broken rice. Pre-washed rice showed increased amylograph peak viscosity and reduced setback values. On the other hand, pre-washed broken rice showed decreased peak viscosity and increased setback values. Differential scanning calorimetry (DSC) results showed that the pre-washing process reduced gelatinization onset- and peak temperatures, with increased gelatinization enthalpy. Total bacteria and yeast count were lower in the pre­washed rice, suggesting the pre-washing process could partially eliminate microbial contamination of ordinary milled rice.

• KOREAN JOURNAL OF CROP SCIENCE
• /
• v.57 no.3
• /
• pp.226-232
• /
• 2012

Through the sampling four rice cultivars with differing amylose contents, the relationship between the structural and gelatinization properties of endosperm starches was analyzed. These rice varieties exhibited different chain length distribution ratio within the amylopectin cluster as well as varing amylose levels. The proportion of amylopectin short chains of in Goami cutlivars was higher than the other varieties, whereas the Goami 2 which shows amylose extender mutant properties in the endosperm showed the highest proportion of long chains. In X-ray diffraction analysis of rice starches, the Goami 2 variety displayed a B-type pattern whereas the other varieties were all A-type. Among the cultivars with high and normal rice starch levels, those with the higher amylose contents showed distinctly lower swelling. Goami 2 rice was found to have the highest onset and peak gelatinization temperature from the differential scanning calorimetry results. The four rice cultivars under analysis also showed different rates of hydrolysis by amyloglucosidase. These findings suggest that the composition and chemical structure of the starch content is a major determinant of both the gelatinization and functional properties of rice.

• Korean Journal of Food Science and Technology
• /
• v.31 no.6
• /
• pp.1542-1548
• /
• 1999

Seven rice varieties(Suweonjo, Suweon232, BG276-5, IR44, IR41999-139, Suweon230 and Yongjubyeo) were used to study the effect of particle size on the physicochemical properties(proximate analysis, color values, amylogram, water absorption index and water solubility index) of rice flours. Suweonjo had the highest amylose content (27.07%) and Yongjubyeo had the lowest one (17.17%). Suweonjo had the highest protein content (11.36%) and IR44 had the lowest one (6.75%). Protein content of rice flours prepared in a pin mill was decreased as particle size of rice flours decreased. L value of rice flour was increased as particle size of rice flours decreased while b value and ${\Delta}E$ value decreased. Maximum viscosity, cold paste viscosity, breakdown, total setback in amylogram properties were increased as particle size of rice flours decreased while initial paste temperature decreased. Water absorption index (WAI) and water solubility index (WSI) were increased as particle size of rice flour decreased.

• Proceedings of the Korean Society of Crop Science Conference
• /
• 2017.06a
• /
• pp.287-287
• /
• 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.

• Korean Journal of Food Science and Technology
• /
• v.31 no.5
• /
• pp.1254-1261
• /
• 1999

The influence of addition of arrow(Pueraria hirsuta Matsum) root flour and its fractions by ultrafiltration on the flow properties of the rice flour-water systems were investigated. The flow properties of rice flour pastes during cold storage$(5^{\circ}C)$ were measured and the components from arrow root flour responsible for changes of flow properties were screened. Addition of arrow root flour significantly changed the flow properties of rice flour pastes. Permeate fractions by ultrafiltration, representing low molecular weight component fraction, significantly affected the flow property of rice flour paste stored at $5^{\circ}C$. Addition of permeate fraction to rice flour pastes rapidly decreased the consistency index, yield stress and pseudoplasticity, and showed a stability of flow property during storage suggesting the retardation of rice starch retrogradation. Permeate fractions of ultrafiltration were identified as puerarin, daidzein and daidzin known to representive isoflavonoid from arrow root.