scholarly journals Occurrence of abnormally cooked rice and water uptake by polished rice at high temperature.

1990 ◽  
Vol 43 (3) ◽  
pp. 215-220
Author(s):  
Aijiro YAMAMOTO ◽  
Hiroshi NAKAJIMA ◽  
Naoko TANIDA
Keyword(s):  
High Temperature ◽  
Water Uptake ◽  
Cooked Rice ◽  
Polished Rice

PROTON-CONDUCTING POLYMERS AS ELECTROLYTE FOR FUEL CELLS

NANO ◽  
2008 ◽  
Vol 03 (05) ◽  
pp. 381-386 ◽  
Author(s):  
DANIELA EBRASU ◽  
IOAN STAMATIN ◽  
ASHOK VASEASHTA
Keyword(s):  
Fuel Cells ◽  
High Temperature ◽  
Conducting Polymers ◽  
Polymer Electrolyte ◽  
Water Uptake ◽  
Water Retention ◽  
Polymer Electrolyte Membrane ◽  
Electrolyte Membrane ◽  
Simple Processing ◽  
Processing Steps

The objective of this investigation is to evaluate a series of polymer electrolyte membrane materials based on sulfonated ladder pyridine polymers and SiO 2 nanoparticles that enhance water retention and favor high temperature (> 120°C) applications. Nanoparticles are used to improve water uptake at levels of 20–38% to increase the level of sulfonation. A study of relevant characteristics of these polymers will provide an alternative to existing polymers, thus offering simple processing steps, as well as nonexotic polymers and higher performances.

Distribution of Radioactive Cesium (134Cs plus 137Cs) in Rice Fractions during Polishing and Cooking

2015 ◽  
Vol 78 (3) ◽  
pp. 561-566 ◽  
Author(s):  
MAYUMI HACHINOHE ◽  
TOMOYA OKUNISHI ◽  
SHOJI HAGIWARA ◽  
SETSUKO TODORIKI ◽  
SHINICHI KAWAMOTO ◽  
...  
Keyword(s):  
Food Processing ◽  
Brown Rice ◽  
Wash Water ◽  
Radioactive Cesium ◽  
Retention Factors ◽  
Cooked Rice ◽  
Polished Rice ◽  
Adequate Understanding ◽  
Cesium 137 ◽  
Processing Factors

We investigated the distribution of cesium-134 (134Cs) and cesium-137 (137Cs) during polishing and cooking of rice to obtain their processing factors (Pf) and food processing retention factors (Fr) to make the information available for an adequate understanding of radioactive Cs dynamics. Polishing brown rice resulted in a decreased radioactive Cs concentration of the polished rice, but the bran and germ (outer layers) exhibited higher concentrations than brown rice. The Pf values for 100% polished rice and outer layers ranged from 0.47 to 0.48 and 6.5 to 7.8, respectively. The Fr values for 100% polished rice and outer layers were 0.43 and 0.58 to 0.60, respectively. The distribution of radioactive Cs in polished rice and outer layers was estimated at approximately 40 and 60%, respectively. On the other hand, cooked rice showed significantly lower levels of radioactive Cs than polished rice, and transfer of radioactive Cs into wash water was observed. The Pf and Fr values for cooked rice were 0.28 and 0.65 to 0.66, respectively. From these results, we can calculate that if the radioactive Cs concentration in brown rice is 100 Bq/kg, the concentrations of Cs in polished rice and cooked rice will be 47 to 48 Bq/kg and 13 Bq/kg, respectively.

scholarly journals Starch Morphology and Metabolomic Analyses Reveal That the Effect of High Temperature on Cooked Rice Elongation and Expansion Varied in Indica and Japonica Rice Cultivars

Agronomy ◽  
2021 ◽  
Vol 11 (12) ◽  
pp. 2416
Author(s):  
Nnaemeka Emmanuel Okpala ◽  
Mouloumdema Pouwedeou Potcho ◽  
Muhammad Imran ◽  
Tianyue An ◽  
Gegen Bao ◽  
...  
Keyword(s):  
High Temperature ◽  
Low Temperature ◽  
Oryza Sativa L ◽  
Effect Of Temperature ◽  
Japonica Rice ◽  
Rice Cultivars ◽  
Starch Granules ◽  
Cooked Rice ◽  
Temperature Regimes ◽  
Badh2 Gene

Rice (Oryza sativa L.) is mainly grouped into indica and japonica varieties. The aim of this study was to investigate the effect of temperature on cooked rice elongation, cooked rice expansion, and rice fragrance. This study was conducted in three growth temperature chambers with indica cultivar Basmati 385 (B385) and japonica cultivar Yunjingyou (YJY). Grains of B385 grown in low-temperature regimes had the highest cooked rice elongation and expansion, whereas the grains of YJY grown in high-temperature regimes had the highest cooked rice elongation and expansion. Starch granules of B385 grown in low-temperature regimes were more compact and bigger, compared to grains grown in medium- and high-temperature regimes. Conversely, the starch granules of YJY grown in high-temperature regimes were more compact and bigger, compared to those grown in medium- and low-temperature regimes. Metabolomic analyses showed that temperature affected the rice metabolome and revealed that cyclohexanol could be responsible for the differences observed in cooked rice elongation and expansion percentage. However, in both B385 and YJY, grains from low-temperature regimes had the highest 2-AP content and the lowest expression levels of the badh2 gene. The findings of this study will be useful to rice breeders and producers.

Fate of Aflatoxin B1 during the Cooking of Korean Polished Rice

2005 ◽  
Vol 68 (7) ◽  
pp. 1431-1434 ◽  
Author(s):  
JE WON PARK ◽  
CHAN LEE ◽  
YOUNG-BAE KIM
Keyword(s):  
Body Weight ◽  
Aflatoxin B1 ◽  
High Performance ◽  
Daily Intake ◽  
The United States ◽  
Cooked Rice ◽  
Polished Rice ◽  
Mutagenicity Assay ◽  
Processing Factors

The fate of aflatoxin B1 (AFB1), a mycotoxin known to occur in polished rice, during rice cooking was evaluated to determine reduction in AFB1 residues and mutagenic potentials. The amounts of AFB1 in three lots of naturally contaminated polished rice from Korea were analyzed by high-performance liquid chromatography after washing and after steaming. An in vitro mutagenicity assay with Salmonella Typhimurium TA100 was used to confirm the results of the chemical analyses. Cooking significantly reduced AFB1 (mean reduction, 34%) in naturally contaminated polished rice and reduced mutagenicity by ca. 27%. Processing factors (reflecting the removal of AFB1 residues during processing) for cooked rice were estimated at 0.66 to 0.73, as determined chemically and toxicologically, respectively. The revised Korean provisional daily intake of AFB1 from consumption of rice as a dietary staple (0.58 to 3.94 ng/kg of body weight per day) is still higher than that reported for foods in general in the United States (0.26 ng/kg of body weight per day). Thus, Koreans probably consume higher amounts of foodborne AFB1 than do Americans and thus are at higher risk for AFB1-induced health consequences.

scholarly journals The Relationship Between the Sensory Properties of Cooked Rice and the Water Uptake of Raw Rice.

2002 ◽  
Vol 49 (1) ◽  
pp. 32-39 ◽  
Author(s):  
Shoji MIWA ◽  
Akira KURODA ◽  
Hideharu ODA ◽  
Tomohisa TAKAYA ◽  
Katsuyoshi NISHINARI
Keyword(s):  
Water Uptake ◽  
Sensory Properties ◽  
Cooked Rice ◽  
The Relationship

Impact of milling and water-to-rice ratio on cooked rice and wastewater properties

2012 ◽  
Vol 18 (3) ◽  
pp. 291-298 ◽  
Author(s):  
MC Altheide ◽  
RO Morawicki ◽  
TJ Hager
Keyword(s):  
Water Uptake ◽  
Amylose Content ◽  
Aluminum Foil ◽  
Environmental Concerns ◽  
Total Solids ◽  
Volumetric Expansion ◽  
Cooked Rice ◽  
Milling Duration ◽  
Cooking Water

Due to the environmental concerns and expense associated with the disposal of wastewater after industrial cooking of rice, the purpose of this study was to evaluate the extent of leaching, water uptake and volumetric expansion of rice during cooking at various milling durations and water-to-rice ratios. Two cultivars of Arkansas rice, a long grain (Francis) and a medium grain (Jupiter), were milled for 10, 20, and 30 s with a laboratory mill. Samples were cooked in aluminum foil covered beakers at water-to-rice ratios of 10:1, 15:1, and 20:1. After 20 min, rice was weighed for water uptake and measured for volumetric expansion using hexane displacement. The excess cooking water was evaluated for total solids, amylose, and protein to determine the extent of leaching. Water uptake and volumetric expansion significantly increased with milling duration in both cultivars. Leached solids increased as the water-to-rice ratio increased in Francis and increased with milling duration in Jupiter; however, the amylose content of leached solids was unaffected by the water-to-rice ratio in both cultivars. Thus, shorter milling durations may limit the extent of leaching during cooking, as observed with Jupiter, while a lower water-to-rice ratio may reduce wastewater contamination for cultivars similar to Francis.

Effect of Cooking on Levels of Ethylene Dibromide Residues in Rice

1985 ◽  
Vol 68 (4) ◽  
pp. 710-711
Author(s):  
Marion Clower ◽  
James P Mccarthy ◽  
Diane M Rains
Keyword(s):  
Environmental Protection ◽  
Environmental Protection Agency ◽  
Analytical Procedure ◽  
Protection Agency ◽  
Analytical Methodology ◽  
Ethylene Dibromide ◽  
White Rice ◽  
Cooked Rice ◽  
Polished Rice ◽  
Rice Samples

Abstract Two studies were conducted to determine the effect that cooking has on the level of residues of ethylene dibromide (EDB) in rice. In the first study, 4 samples of long and medium grain polished white rice containing 113, 295, 956, and 1568 ppb EDB were cooked according to typical label directions. Three batches of cooked rice were prepared from each sample of polished rice and frozen until analysis; each batch was analyzed in duplicate. EDB levels in all cooked rice samples were <10 ppb. In the second study, conducted jointly by the Food and Drug Administration (FDA) and the Environmental Protection Agency (EPA), a sample of medium grain polished white rice containing about 1600 ppb EDB was cooked by each laboratory. Overall average EDB levels in rice analyzed immediately after cooking were 16 and 37 ppb for FDA and EPA, respectively. The corresponding frozen samples contained 8 and 39 ppb EDB. The 2 laboratories exchanged these frozen samples and reanalyzed them to check variability in the analytical procedure. FDA found 49 ppb EDB in the sample cooked by EPA and EPA found 8 ppb EDB in the sample cooked by FDA, thus indicating that analytical methodology was not a major source of variability. The range of EDB levels was therefore attributed to minor differences in the way the rice was cooked or handled immediately after cooking.

Fate of Ochratoxin A during Cooking of Naturally Contaminated Polished Rice

2005 ◽  
Vol 68 (10) ◽  
pp. 2107-2111 ◽  
Author(s):  
JE WON PARK ◽  
SOO-HYUN CHUNG ◽  
CHAN LEE ◽  
YOUNG-BAE KIM
Keyword(s):  
Ochratoxin A ◽  
High Performance ◽  
Glioma Cells ◽  
In Vitro Cytotoxicity ◽  
C6 Glioma Cells ◽  
Cytotoxic Potential ◽  
Cooked Rice ◽  
Polished Rice ◽  
Low Levels

Ochratoxin A (OTA), a mycotoxin widespread in cereals, occurs in polished rice that is consumed as cooked rice after washing and steaming. Cooking decreases OTA levels in food to varying extents, but little is known about how cooking changes the biological activity of this mycotoxin. We therefore evaluated the fate of OTA during rice cooking to determine the OTA residues and cytotoxic potential in vitro. Water-washed rice, ordinary cooked rice, and pressure-cooked rice were prepared from three polished rice lots naturally contaminated with OTA. Residual OTA in each sample was analyzed by high-performance liquid chromatography (HPLC), whereas in vitro cytotoxicity of OTA to C6 glioma cells, susceptible to low levels (nanograms per milliliter) of OTA, was used to confirm the chemical analysis. OTA concentration, as determined by HPLC analysis, in the cooked rice by both types of cookers was significantly lower than (59 to 75%) in the raw polished rice and water-washed rice. The cytotoxicity of the OTA that remained in the pressure-cooked rice from three lots was markedly decreased (approximately 20%, P < 0.05) when compared with other samples in respective lots. This confirms that cooking lowers OTA residues. Although washing polished rice with water had little effect on OTA levels, pressure steaming appeared to be the critical cooking step not only to reduce OTA residues in polished rice before reaching the consumer as the dietary staple of cooked rice, but also to diminish cytotoxicity of OTA.

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