• Journal of the Korean Society of Food Science and Nutrition
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• v.42 no.9
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• pp.1370-1377
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• 2013

Rice is widely grown in Asia and is one of the major dietary staples in the world. Also, rice contains antioxidants which can prevent from oxidative stress related diseases, including cancer, atherosclerosis, and diabetes. Because the rice is consumed cooked, the effect of the cooking process on the antioxidative and antigenotoxic properties of rice is lacking. The aim of this study was to determine the effects of cooking on the antioxidant and antigenotoxic effects of white rice (WR), brown rice (BR), and germinated brown rice (GBR). The antioxidant activities were measured for total phenolic content (TPC), DPPH radical scavenging activity (DPPH RSA), total antioxidant capacity (TRAP), and oxygen radical absorbance capacity (ORAC). The highest TPC was found in uncooked BR (18.4 mg gallic acid equivalent/100 g). After cooking, the TPC of WR significantly increased, while the TPC of BR and GBR were reduced by 47.7% and 36.7%, respectively. The $IC_{50}$ for DPPH RSA was not significantly different in uncooked rice, while the DPPH RSA of WR and GBR decreased after cooking and the DPPH RSA of BR significantly increased. TRAP values in BR and GBR increased after cooking, while the value of WR decreased. The ORAC values of uncooked WR, BR, and GBR were 5.3, 4.3, and $3.9{\mu}M$ trolox equivalent at the concentration of $50{\mu}g/mL$. After cooking, the ORAC value of BR remained unchanged, while the value of GBR increased and the value of WR decreased. The antigenotoxic activities of WR, BR, and GBR were determined by measuring the inhibitory effects of $H_2O_2$-induced DNA damage on human leukocytes using the comet assay. The results showed that all rice tested showed a significant antigenotoxic effect against oxidative stress, except for the cooked white rice. Overall, our results indicate the addition of brown rice and/or germinated brown rice to cooked white rice is a good option for improving the benefits of rice.

• Human Ecology Research
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• v.58 no.1
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• pp.121-130
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• 2020

This study evaluated the quality characteristics of semi-dried noodles prepared with various dry rice flours (0, 25, 50, 75, and 100%) in order to develop the most preferred noodle recipe and to increase rice consumption. Amylography measured the viscosity of composite dry rice flour-wheat flour and indicated that the gelatinization point and maximum viscosity decreased as the level of dry rice flour increased. Both L and a values for cooked noodle significantly increased as the dry rice flour increased; however the L value decreased for uncooked of noodles. Weight, volume and water absorption of cooked semi-dried noodles significantly decreased as the dry rice flour increased; however the turbidity of soup increased. Texture properties such as hardness, springiness, cohesiveness, and adhesiveness decreased as the level of dry rice flour increased. As the amount of rice flour added increased, large particles of gluten were reduced while smaller particles of starch increased by scanning electron microscopy (SEM). The color, taste, and overall preference of 75% noodles were the highest in the sensory characteristics. The results, showed that the addition of dry rice flour positively affects the overall sensory characteristics of semi-dried noodle with 75% representing the optimal level for addition.

• Microbiology and Biotechnology Letters
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• v.39 no.3
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• pp.274-280
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• 2011

Effects of rice varieties, fermentation temperature, nuruks and yeast on the quality of yakju (Korean traditional rice wine) were investigated. Among various yakju made by using some rice varieties, Chucheong yakju produced the highest ethanol of 18.9%. The maximum amount of ethanol was produced when 2% nuruk and 0.8% yeast were added to cooked Chucheong rice and fermented at $20^{\circ}C$ for 10 days. This Chucheong yakju also showed the best overall acceptability. Changes of physicochemical properties and sensory evaluation of the 3 kinds of Chucheong yakju made by cooked rice and uncooked rice and gruel rice were investigated during fermentation. Ethanol contents of uncooked rice- Chucheong yakju and gruel rice- Chucheong yakju were significantly increased from 10.6% and 9.9% after 3 days fermentation to 17.1% and 17.2% after 7 days fermentation. Sensory evaluation revealed the gruel rice - Chucheong yakju was the best in total acceptability with sweety and refreshing tastes.

• Korean Journal of Food Science and Technology
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• v.16 no.4
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• pp.463-471
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• 1984

For the eventual alcohol production from uncooked starch, an efficient saccharification process was examined by using the combined action of steeping, pectin depolymerase, ${\alpha}-amylase$ and glucoamylase. The total sugar content of rice, sweet potato and tapioka used were 4.53, 4.26, and 3.92 mmole/g sample. $70\;{\pm}\;10%$ of the total sugar was hydrolyzed when cooked starch was saccharified under the condition which is currently used in industry. The smaller starch particle was used, the more saccharification was obtained. Efficient saccharification was obtained by treatment with 5% $H_2SO_4$ (sample: working volume = 1:2) at $60^{\circ}C$ for 12 hr. Optimization was carried out for the saccharification of uncooked starch by the combined action of pectin depolymerase, ${\alpha}-amylase$, and glucoamylase. The conditions are: pectin depolymerase; pH 4.5, $45^{\circ}C$, 2 hr, ${\alpha}-amylase$; pH 6.0, $60^{\circ}C$, 1 hr, and glucoamylase; pH 3.5, $60^{\circ}C$, 1 hr. Simultaneous treatment of the combined action of macerating, liquifying and saccharifying enzymes yielded better result than stepwise treatment of 3 enzymes. Degrees of saccharification of uncooked tapioka, rice and sweet potato were 82, 90.5, and 84.5%, respectively on the basis of total sugar, under the optimized conditions.

• KSBB Journal
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• v.27 no.4
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• pp.251-256
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• 2012

In this study we investigated the effect of temperature on the two-stage fermentation of Makgeolli using uncooked germinated black rice. The fermentation processes were conducted at $15^{\circ}C$ for three weeks and $25^{\circ}C$ for 7 days. The pH of Makgeolli at $25^{\circ}C$ increased from pH3.0 to pH 4.2, which was consistent with that at $15^{\circ}C$. In contrast total acidity of Makgeolli at $15^{\circ}C$ was about half of that at $25^{\circ}C$ (0.36% and 0.59%, respectively). By the 7 days-fermentation at $25^{\circ}C$, 11% of alcohol was produced, whereas three weeks were required for the same alcohol production at $15^{\circ}C$. In the case of sugar contents, the amounts of total glucose-equivalent reducing sugars and glucose increased at the end of the fermentation at $25^{\circ}C$ up to 2.25 mg/mL and 3.4 mM, respectively, whereas those at $15^{\circ}C$ were maintained at very low levels (0.18 mg/mL and 0.1 mM, respectively). Such limited supplement of sugars at $15^{\circ}C$ seemed to affect metabolism of yeast, resulting in different composition of organic acid. At $25^{\circ}C$, citric acid that was 73.4 ppm at the initial fermentation was consumed completely, whereas 20 ppm of citiric acid was remained at $15^{\circ}C$. In addition, acetic acid and lactic acid in Makgealli at $15^{\circ}C$ were 53% and 14% of those at $25^{\circ}C$.

• Food Science of Animal Resources
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• v.27 no.2
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• pp.228-234
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• 2007

The purpose of this study was to investigate quality characteristics of the meat batter containing dietary fiber extracted rice bran. The formulations of meat batters were manufactured in a model system with 2% raw rice bran and 2, 4, 6% levels of dietary fiber extracted rice bran, respectively. The proximate compositions of dietary fiber extracted rice bran were 53.27% dietary fiber, 6.10% crude fat, 22.99% crude protein, 12.78% crude moisture, and 7.41% crude ash. Compared with control of uncooked meat batter, the pH value of all treatments were significantly different(p<0.05). The pH of cooked meat batter were similar to uncooked meat batter. $CIE\;L^*-\;and\;CIE\;b^*-value$ of uncooked meat batter containing dietary fiber extracted rice bran were lower than control, but CIE $a^*-value$ of treatment was higher than those in control(p<0.05). All treatments had significantly lower cooking loss and emulsion stability than control(p<0.05). Compared with control, viscosity of the treatments containing dietary fiber extracted rice bran were observed significantly higher than those in control (p<0.05). And then hardness, cohesiveness, gumminess, and chewiness of treatments were higher than in control(p<0.05). Conclusively, the results of this study showed that addition of dietary fiber extracted rice bran affected the high quality properties of meat batter.

• Applied Biological Chemistry
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• v.27 no.3
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• pp.198-203
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• 1984

Ethanol fermentation of chemically gelatinized starch and uncooked raw starch was nested with various starchy materials. Starches were gelatinized by 5.4% NaOH and neutralized by sulfuric acid. The patterns of $CO_2$ evolving and the ethanol yield for the chemically gelatinized starch resemble those obtained with thermally gelatinized starch. The alcoholic fermentation of raw starch was carried out by the simultanous saccharification-fermentation using a commercial glucoamylase and yeast. Ethanol yield from uncooked rice starch fermentation was highly comparable to that from cooked one. $CO_2$ evolving rates of the uncooked starches of corn, barley, tapioca and sweet potato were lower than those of the cooked starches. However, the final ethanol yields were similar or slightly lower, depending on the types of starch.

• Food Science of Animal Resources
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• v.29 no.2
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• pp.260-268
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• 2009

This study was conducted to determine the effects of added rice bran fiber on the physicochemical and sensory characterization of blood sausage. Blood sausages were supplemented with rice bran fiber at levels of 0% (control), 1%, 2%, and 3%. The moisture, hardness, gumminess, and chewiness of treatments with added rice bran fiber were higher than those of controls (p<0.05). The pH, lightness, redness, and yellowness of uncooked as well as cooked blood sausages increased with increasing addition levels of rice bran fiber levels, but energy values were lower in blood sausage treatments with containing rice bran fiber than that of controls (p<0.05). As the increase levels of rice bran fiber in blood sausage the energy levels were decreased (p<0.05). All sensory scores of treatments containing rice bran fiber were higher than controls, and the highest overall acceptability was attained when 2% rice bran fiber was added to blood sausage. The blood sausage with 2% rice bran fiber can be manufactured with high quality characteristics.

• Journal of the Korean Society of Food Science and Nutrition
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• v.32 no.3
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• pp.375-380
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• 2003

The study was carried out to set up alcohol fermentation condition for uncooked brown rice. Response surface methodology (RSM) was applied to optimize and monitor of the alcohol fermentation condition with uncooked brown rice. The primary variables were conducted the reaction surface regression analysis for the particle size of brown rice (20 40 60 mesh) the enzyme content (0.1,0.3,0.5%) and the agitating rate (0,100,200 rpm). Their optimization was 35~42 mesh for the size of particle and 0.32~0.43% for enzyme content by SAS (Statistical Analysis System). The coefficient of determination ($R^2$) in ingredients was admitted at the significant level of 5~10% in all ingredients except for a reducing sugar. Predicted values at optimum alcohol fermentation condition agreed with experimental values. During the fermentation, pH was decreased from 6.25 to 4.34, and total acidity was increased from 0.15 to 0.2. The amino acidity was decreased from 1.88 to 0.92, reducing sugar and total sugar contents were decreased 213 mg% and 1,077 mg%, respectively. Alcohol content was increased to 10% after 48 hr fermentation.

• Korean Journal of Food Science and Technology
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• v.26 no.4
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• pp.442-447
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• 1994

Effect of different mixing ratio of non-glutinous and glutinous rice on physical and rheological properties of extrudate prepared in a single screw extruder were examined. The extrusion conditions in term of screw speeds, moisture content and die temperature were 258 rpm, 18% and $120^{\circ}C$, respectively. The resisdence time distribution of the most of materials were within 30 second and small portion of them went up to 80 second. The expansion ratio was the highest value (2.93) for 70% of glutinous rice in the mixture, while the lowest value for 100% of non-glutinous rice. Breaking strength was in the range between 1,051g and 1,117g for $10{\sim}20%$ of glutinous rice in the mixture, while the lowest value (737g) for 80%r of glutinous rice. As the amount of glutinous rice increased, L and a values were increased and b value was decreased. The uncooked cold paste viscosity had 400 B.U. for 100% non-glutinous rice , while no peak for the 100% glutinous rice. As the amount of glutinous rice increased up to 100%, the water absorption index (WAI) was decreased, while water solubility index (WSI) was increased. The rheological properties of extrudate were accounted by the law of Oswald. The flow behavior index of extrudate was less than 1.0, which showed pseudoplastic behavior. Yield stress was the highest value for 20% of glutinous rice in the mixture and the lowest value for $80{\sim}100%$ of glutinous; rice. Number of air cell was between 128 and 159 for $80{\sim}100%$ of glutinous rice in the mixture, while $81{\sim}84%$ for $0{\sim}20%$ of glutinous rice. The degree of shapefact was increased more when the mixtures of glutinous and non-glutinous rice was used than when glutinous or non-glutinous rice was only used.