A STUDY OF HEAD RICE YIELD REDUCTION OF LONG- AND MEDIUM-GRAIN RICE VARIETIES IN RELATION TO VARIOUS HARVEST AND DRYING CONDITIONS

2000 ◽  
Vol 43 (6) ◽  
pp. 1709-1714 ◽  
Author(s):  
J. Fan ◽  
T. J. Siebenmorgen ◽  
W. Yang
Keyword(s):  
Rice Yield ◽  
Yield Reduction ◽  
Rice Varieties ◽  
Head Rice ◽  
Head Rice Yield ◽  
Drying Conditions

Head rice yield response to low and high drying and tempering conditions

2013 ◽  
Vol 27 (2) ◽  
pp. 219-223 ◽  
Author(s):  
M. Sadeghi ◽  
E. Nasrnia ◽  
A.A. Masoumi ◽  
A. Hemmat
Keyword(s):  
Moisture Content ◽  
Rice Yield ◽  
Yield Response ◽  
Rice Varieties ◽  
Head Rice ◽  
Rough Rice ◽  
Head Rice Yield ◽  
Yield Values ◽  
High Head ◽  
Drying Conditions

Abstract The influence of drying and tempering conditions on head rice yield of long- and medium-grain rough rice varieties was investigated. The head rice yield values for the medium-grain variety at high drying conditions and 1.5 and 3% points moisture content removal were even significantly higher than the corresponding values for the long-grain variety at low drying conditions. 1.5% points moisture content removal yielded the least damage to the rough rice. Under low drying conditions, tempering had no meaningful effect on head rice yield for all drying durations. For both varieties, using high drying conditions with 6% points moisture content removal at first drying stage associated with 120 min tempering duration could be suggested as a rapid and energysaving operation to achieve high head rice yield values.

HEAD RICE YIELD REDUCTION RATES CAUSED BY MOISTURE ADSORPTION

1990 ◽  
Vol 33 (4) ◽  
pp. 1263-1269 ◽  
Author(s):  
M. M. Banaszek ◽  
T. J. Siebenmorgen
Keyword(s):  
Rice Yield ◽  
Yield Reduction ◽  
Moisture Adsorption ◽  
Head Rice ◽  
Head Rice Yield

Effect of Post-Drying Tempering of Rice on Minimizing Kernel Fissuring and Maximizing Moisture Removal

2021 ◽  
Vol 65 (1) ◽  
pp. 1-9
Author(s):  
Zephania Odek ◽  
Terry J. Siebenmorgen ◽  
Andronikos Mauromoustakos ◽  
Griffiths G. Atungulu
Keyword(s):  
Rice Yield ◽  
Yield Reduction ◽  
List Type ◽  
Humidity Ratio ◽  
Percentage Points ◽  
X Ray Imaging ◽  
Head Rice ◽  
Rough Rice ◽  
Head Rice Yield ◽  
Rice Drying

HighlightsMore moisture can be removed in a single drying pass without severely fissuring kernels when samples are tempered than when immediately cooled without tempering.Tempering rice kernels immediately after drying can reduce the percentage of fissured kernels by up to half of that when kernels are immediately cooled without tempering.Abstract. Improper rice drying results in kernel fissuring, leading to head rice yield reduction due to breakage during milling. The objective of this study was to determine the percentage points (pp) of moisture content (MC) reduction that can be achieved in a single drying pass without significantly fissuring kernels. Long-grain rough rice of cultivars CL XL745 and Diamond at initial MCs of 18%, 17%, 16%, 15%, and 14% were dried using air at 45°C/20% relative humidity (RH), 50°C/15% RH, 55°C/12% RH, 60°C/10% RH, and 65°C/8% RH to MCs of 17%, 16%, 15%, 14%, 13%, or 12% with and without post-drying tempering. All temperature/RH combinations resulted in a humidity ratio of 0.012 kg water kg-1 dry air. Tempering was conducted at the drying air temperature for 4 h. The resulting samples achieved between 1 and 7 pp of MC reduction in a single drying pass. The pp of MC reduction that can be attained in a single drying pass without causing significant fissuring varied across the cultivars tested. Generally, ~2 pp of MC reduction was achieved in a single drying pass for CL XL745 and ~4 pp for Diamond without causing adverse fissuring when samples were not tempered after drying. However, with tempering, ~3.5 pp of MC reduction was achieved in a single drying pass for CL XL745 and ~5.5 pp for Diamond without causing significant fissuring. However, these amounts varied depending on the drying air conditions and initial MC. For both cultivars, tempering immediately after drying reduced the fissured kernel percentage by up to half of that when the kernels were not tempered. These findings quantify the importance of rice tempering and provide information on how much moisture can be safely removed in a single drying pass. Such findings may be applied to different dryer types to reduce fissuring due to drying, thereby minimizing head rice yield reductions. Keywords: Drying, Glass transition, Rice quality, Single-pass drying, X-ray imaging.

RELATING DRYING RATE CONSTANT TO HEAD RICE YIELD REDUCTION OF LONG-GRAIN RICE

1997 ◽  
Vol 40 (4) ◽  
pp. 1133-1139 ◽  
Author(s):  
H. Chen ◽  
T. J. Siebenmorgen ◽  
B. P. Marks
Keyword(s):  
Rate Constant ◽  
Rice Yield ◽  
Yield Reduction ◽  
Drying Rate ◽  
Head Rice ◽  
Head Rice Yield

Rice cultivar response to sublethal concentrations of glyphosate and paraquat late in the season

2020 ◽  
pp. 1-7
Author(s):  
Justin McCoy ◽  
Bobby Golden ◽  
Jason Bond ◽  
Darrin Dodds ◽  
Taghi Bararpour ◽  
...  
Keyword(s):  
Grain Yield ◽  
Growth Stage ◽  
Rice Yield ◽  
Yield Reduction ◽  
Rice Grain ◽  
Rice Cultivars ◽  
Head Rice ◽  
Rough Rice ◽  
Head Rice Yield ◽  
Sublethal Concentrations

Abstract Differential tolerance may be observed among rice cultivars with desiccant exposure events during rice reproduction and ripening. Five field studies were established at the Mississippi State University Delta Research and Extension Center in Stoneville, MS, to determine the effects of exposure to sublethal concentrations of common desiccants across multiple rice cultivars. Rice cultivars in the study were ‘CLXL745’, ‘XL753’, ‘CL163’, ‘Rex’, and ‘Jupiter’. Desiccant treatments included no desiccant, paraquat, or glyphosate and were applied at the 50% heading growth stage respective to cultivar. Differential injury estimates among cultivars and desiccant treatments was observed when glyphosate or paraquat was applied at 50% heading. Injury from glyphosate at 50% heading was nondetectable across all cultivars. However, injury following paraquat applications was >7% across all rating intervals and cultivars. Hybrid cultivars exhibited less injury with paraquat applications than the inbred cultivars in the study. Rice following exposure to glyphosate or paraquat at 50% heading growth stage produced rough rice grain yield decreases ranging from 0% to 20% and 9% to 21%, respectively. Rough rice grain yield decreases were observed across all cultivars following paraquat exposure, and all inbred cultivars following glyphosate exposure. Across desiccant treatment, head rice yield was reduced in three of five cultivars in the study. When pooled across cultivar, paraquat applications cause a head rice yield reduction of 10%, whereas rice yield following glyphosate application remained >95%. Although differential tolerance among cultivars to paraquat or glyphosate exposure was observed, impacts on grain quality coupled with yield reductions suggests extreme rice sensitivity to exposure to sublethal concentrations of these desiccants at the 50% heading growth stage.

Milled Rice Quality Assessment

2010 ◽  
Vol 6 (2) ◽  
Author(s):  
Reza Farahmandfar ◽  
Esfandiyar Farahmandfar ◽  
Mahdi Ghasemi Varnamkhasti ◽  
Mahdi Zarei
Keyword(s):  
Rice Yield ◽  
Milling Process ◽  
Milled Rice ◽  
Rice Varieties ◽  
Breeding Lines ◽  
Head Rice ◽  
Rough Rice ◽  
Degree Of Milling ◽  
Head Rice Yield ◽  
Important Processing

Milling, an important processing step of rough rice, is usually done to produce white, polished grains. In this paper the quality of 22 milled rice varieties, common in Mazandaran, Iran, are investigated. These rice varieties included local varieties and breeding lines. Parameters assessed were head rice yield, degree of milling, husk removed percent, and total milling recovery. Results obtained revealed that the Tarom Mahali and Champa varieties have the highest head rice yield as 60.58 and 66.39 % and total milling recovery as 69.96 and 71.38 %, respectively. The greatest degree of milling value was found for the Haraz variety with a mean of 16.06 %. Also, it was found that the husk removed percent values were not statistically different among the varieties studied. Finally, considering all results obtained, the varieties of Tarom Mahali, Champa, and Neda showed to be more economical in the milling process.

Effects of drying conditions on head rice yield and browning index of parboiled rice

2001 ◽  
Vol 47 (1) ◽  
pp. 37-41 ◽  
Author(s):  
Germán Elbert ◽  
Marcela P Tolaba ◽  
Constantino Suárez
Keyword(s):  
Rice Yield ◽  
Browning Index ◽  
Parboiled Rice ◽  
Head Rice ◽  
Head Rice Yield ◽  
Drying Conditions

scholarly journals Effect of Parboiling Conditions on Physical and Cooking Quality of Selected Rice Varieties

2020 ◽  
Vol 2020 ◽  
pp. 1-9
Author(s):  
Ayenew Meresa ◽  
Ayalew Demissew ◽  
Seifu Yilma ◽  
Getu Tegegne ◽  
Kiber Temesgen
Keyword(s):  
Water Uptake ◽  
Rice Yield ◽  
Rice Variety ◽  
Uptake Ratio ◽  
Rice Varieties ◽  
Broken Rice ◽  
Head Rice ◽  
Head Rice Yield ◽  
Soaking Temperature

Most locally cultivated rice varieties in Ethiopia have low physical (low head rice yield, high broken rice yield, and high percentage of chalkiness) and cooking qualities (low water uptake ratio and swelling ratio). Parboiling, a process which involves soaking, steaming, and drying, has been identified as a key technique to improve cooking and milling quality of rice. The current study is aimed at elucidating the effect of parboiling on physical and cooking qualities of three rice varieties (Gumara, Edget, and Narica4) collected from Fogera National Rice Research and Training Center, Amhara region, Ethiopia. Each rice variety was subjected to different soaking temperatures (40°C, 50°C, 60°C, 70°C, and 80°C) and steaming time (10, 20, 30, 40, and 50 minutes). The treatment effect results indicated that parboiling has a significant effect (P<0.05) on head rice yield and percentage of broken rice with increased soaking temperature and steaming time as compared to the control. For instance, percent head rice yield increased as soaking temperature (from 40 to 80°C) and steaming time (from 10 to 50 min) increased: for Gumara, from 4.07 to 93.6%, for Edget, 9.47 to 96.53, and from 3.20 to 91.67 for Narica4. Percentage chalkiness had decreased as soaking temperature and steaming time increased: 97.33% to 0.00% for Gumara, 97.80% to 0.00% for Edget, and 100.00% to 0.13% for Narica4 as compared to 100% for control of all varieties. The minimum cooking time was identified as 16-23 min for Gumara, 16-23 min for Edget, and 15-20 min for Narica4 rice varieties. The result of the present study clearly showed that parboiling with high soaking temperature and steaming time increased the head rice yield, water uptake ratio, decreased percentage chalkiness, and enhanced the overall quality of the rice varieties.

Effects of Rice Kernel Thickness on Head Rice Yield Reduction Due to Moisture Adsorption

1994 ◽  
Vol 37 (2) ◽  
pp. 487-490 ◽  
Author(s):  
V. K. Jindal ◽  
T. J. Siebenmorgen
Keyword(s):  
Rice Yield ◽  
Yield Reduction ◽  
Moisture Adsorption ◽  
Head Rice ◽  
Head Rice Yield
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