• Korean Journal of Food Science and Technology
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• v.47 no.6
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• pp.793-796
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• 2015

The in-vitro starch digestibility of white and brown rice flours was continuously characterized from a rheological point of view. Specifically, the in-vitro viscosities of the rice digesta samples were monitored under simulated oral, gastric, and intestinal conditions. A trend of decreasing viscosities in all the digesta samples was observed during the in-vitro digestion. After cooking, the brown rice sample exhibited lower viscosity than that of the white rice flour due to the presence of more non-starch components. A similar tendency was observed during the simulated oral and gastric digestions. However, the viscosity crossover between the white and brown rice samples was observed during intestinal digestion. In addition, the amount of glucose released from the brown rice flour was significantly lower than that from the white rice flour. Thus, the slower rate of starch hydrolysis in the brown rice flour could be related to its in-vitro rheological behaviors.

• Preventive Nutrition and Food Science
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• v.2 no.4
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• pp.301-303
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• 1997

To elucidate the contents of phytic acid and minerals in rice produced in Korea, samples of 68 verieties of brown rice and 9 varieties of polished rice were analyzed for phytic acid by colorimetric method, and Ca, Fe, Mg and Zn contents by the atomic absorption spectrophytometer. Selenium was measured by fluorometry. Averages of phytic acid content of the 68 brown rice were 12.6 g/kg, whereas that of the 8 polished rice were 1.83 g/kg on dry matter. Averages of Ca, Fe, Mg and Zn contents on the 68 brown rice were 111, 7.4, 1,068 and 19.1 mg/kg, and those of the polished rice were 45.6, 2.1, 250 and 14 mg/kg, respectively. A averge of selenium content of the brown rice was 38.3 $\mu\textrm{g}$/kg.

• Preventive Nutrition and Food Science
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• v.16 no.2
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• pp.157-164
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• 2011

The influence of sodium salts and chlorides at various concentrations (0.05, 0.10, 0.50, and 1.00%) on the reheating behavior of retrograded rice starch and cooked rice was investigated. The degree of gelatinization of the all retrograded rice starch gels and the cooked rice containing sodium salts and chlorides increased after reheating compared to the starches without salt. Gelatinization also showed an increasing trend as the concentration of sodium salts and chlorides increased. The increase of gelatinization after reheating the samples containing sodium salts and chlorides was greater than 38.0%. The reheated retrograded rice starch and cooked rice containing $Na_3PO_4$ showed the lowest set back value and retrogradation rate constant. Among all the samples, the cooked sample containing $Na_3PO_4$ showed the highest increment of gelatinization after reheating. Also, this same sample showed the lowest retrogradation degree.

• Korean Journal of Food Science and Technology
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• v.23 no.5
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• pp.619-621
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• 1991

A partial replacement($0{\sim}30%$) of non-waxy rice(Samgangbyeo, Tongil type) was attempted in Yukwa(Korean traditional puffed rice cake) preparation. The yukwa prepared with the replacement of non-waxy rice up to 20% level was comparable in quality to the traditional yukwa in view of expansion rate, crispness and hardness followed by sonsory evaluation. Continuous whipping machine for making yukwa bandaekee(rice cake) could be successfully introduced for mass production.

• Korean journal of food and cookery science
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• v.29 no.1
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• pp.47-52
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• 2013

The effects of added brown rice flour on the quality characteristic of waffle were investigated. Waffle were prepared by the addition of 0%, 25%, 50%, 75% and 100% of brown rice flour on wheat flour. The weight of waffle with brown rice flour ranged from 103.0~107.0 g and that of the control was 100.0 g. The volume of the waffle prepared by adding brown rice flour were 225.0~303.0 mL and that of the control was 307.5 mL. The weight of the waffle increased with increasing brown rice flour concentration, whereas volume and baking loss decreased. The hardness, chewiness (p<0.05) and springiness decreased with the addition of brown rice flour. The Hunter L values of waffle decreased, whereas a and b values increased with the addition of brown rice flour. The result of the sensory evaluation showed that taste and overall acceptability (p<0.05) was the highest for added brown rice flour.

• Food Science and Biotechnology
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• v.17 no.4
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• pp.728-733
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• 2008

New gluten-free food product (tarhana) was produced using rice and com flours. Chemical and sensory properties of the tarhana samples were investigated and compared with those of traditional wheat tarhana. Generally, sensory analysis results indicated that utilization of com and rice flours in tarhana resulted in acceptable soup properties in terms of some of the sensory properties. The changes in electrophoretic properties of the proteins of the tarhana samples were also studied during the tarhana production. Sodium dodecyl sulfate-polyacryamide gel electrophoresis (SDS-PAGE) results showed that relative intensities of some of the protein bands in tarhana samples generally decreased during fermentation. The decrease was more obvious at the larger molecular weight region. Corn and rice tarhana seem to be promising food products for the celiac patients who have limited choice of cereal based foods.

• Korean Journal of Food Science and Technology
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• v.45 no.3
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• pp.333-338
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• 2013

Enzymatic activity in germinated cereal grains is important for the saccharification of starch materials. This study was conducted to investigate the amylolytic activities of germinating brown rice and black rice that have different amylose contents. Brown rice and black rice were steeped at room temperature for 24 h and germinated at 20 and $30^{\circ}C$ for 1, 2, and 3 days. ${\alpha}$- and ${\beta}$-Amylase activities in normal brown rice increased very slightly during the 3-day germination period, but the enzymatic activities were slightly higher in low-amylose (waxy type) brown rice. Diastatic power (DP), a measure of starch-saccharifying enzyme, was higher in the germinating brown rice with low amylose than in those with normal amylose content. ${\alpha}$- and ${\beta}$-Amylase activities in black rice increased gradually during germination, and DP of low-amylose black rice appeared to be higher than that of normal brown rice. Amylase activities in brown rice and black rice germinated at $30^{\circ}C$ were higher than those germinated at $20^{\circ}C$. Compared to brown rice, the overall amylolytic activity of germinated black rice was observed to be higher than that of brown rice.

• The Korean Journal of Food And Nutrition
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• v.31 no.5
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• pp.766-773
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• 2018

The purpose of this study is to make rice pie, a bakery item, to enhance use of rice flour and analyze quality characteristics of rice pie by adding roasted peanut flour and peanut sprout flour. Water content of rice pie adding roasted peanut flour or peanut sprout flour is lower than that of wheat pie. The pH of rice pie is lower than that of wheat pie, and pH becomes higher when roasted peanut flour or peanut sprout flour is added. Density of dough is lower in rice pie than in wheat pie, and when roasted peanut flour or peanut sprout flour is added, rice pie reveals higher density. Loss rate is higher in rice pie than in wheat pie, and when roasted peanut flour or peanut sprout flour is added, rice pie reveals lower loss rate. When roasted peanut flour or peanut sprout flour is added to rice pie, its brightness (L) and yellowness (b) decrease, while redness (a) increases. Hardness is higher in pie made of rice powder than in wheat pie, and when roasted peanut flour or peanut sprout flour is added, hardness becomes lower. Regarding composition of fatty acids in rice pie, saturated fatty acids observed are myristic acids, palmitic acids, and stearic acids. Monounsaturated fatty acids found are mainly oleic acids. Polyunsaturated fatty acids detected are linoleic acids, and are found more in pie made of rice powder, than in wheat pie.

• The Korean Journal of Food And Nutrition
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• v.23 no.4
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• pp.600-606
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• 2010

The objective of this study was to develop functional rice coated with yacon roots extracts and to evaluate the antioxidant properties and physiological activity of rice coated with yacon extract. The washed rice was coated by spraying yacon extract at 10, 20, 30, and $40^{\circ}Brix$ and dried at room temperature. The moisture contents, color changes, antioxidant properties as total polyphenolics and DPPH radical scavenging activity and instrumental texture property and sensory evaluation change in the yacon root extracts coated rice and uncoated cooked rice were observed during 3 days of storage. Increasing the coating concentration was associated with lower color values(L value) and moisture contents. Total phenolics and DPPH radical scavenging properties generally increased in the cooked rice coated with yacon root extract more than the control (non-coated rice). However, D-20($20^{\circ}Brix$ of the yacon root concentration) resulted in better textural properties and sensory overall acceptability in cooked rice on 0 and 3 storage days. It was concluded that the optimum coating ration of rice and added functional yacon rice were $20^{\circ}Brix$ and 7% respectively, in proportion to the total weight of raw rice.

• The Korean Journal of Food And Nutrition
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• v.30 no.3
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• pp.464-472
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• 2017

The qualities of rice cooked on heat plate, induction heat and heat plate with pressure, were investigated. The weight, volume, water soluble index (WSI), hydration by SEM (Scanning Electron Microscope), and gelatinization by DSC (Differential Scanning Calorimetry), as well as the consumer acceptability of cooked rice were analyzed. The weight, volume and WSI of rice cooked on heat plate with pressure were higher than those of rice cooked on heat plate and induction heat. The rice cooked on heat plate with pressure also showed higher degree of hydration and gelatinization, and lower degree of enthalpy of gelatinization than the rice cooked on heat plate and induction heat for 5~15 min. The consumer acceptability revealed that the odor, appearance, taste, texture and overall acceptance of rice cooked on induction heat were better than those of rice cooked on heat plate and heat plate with pressure. During storage in a cooker for 0~12 h, there was a decrease in the consumer acceptability of cooked rice. Overall results indicate that the qualities of rice cooked on induction heat and heat plate with pressure were higher than those of rice cooked on heat plate.