Effect of superheated-steam drying compared to conventional parboiling on chalkiness, head rice yield and quality of chalky rice kernels

2020 ◽  
Vol 87 ◽  
pp. 101627
Author(s):  
Weerachet Jittanit ◽  
Kemika Angkaew
Keyword(s):  
Superheated Steam ◽  
Rice Yield ◽  
Yield And Quality ◽  
Superheated Steam Drying ◽  
Head Rice ◽  
Head Rice Yield ◽  
Steam Drying

scholarly journals Effect of temperature and mode of drying on bioactive compounds and quality of germinated parboiled rice

2018 ◽  
Author(s):  
Busarakorn Mahayothee ◽  
Supaporn Klaykruayat ◽  
Marcus Nagle ◽  
Joachim Müller
Keyword(s):  
Bioactive Compounds ◽  
Rice Yield ◽  
Aminobutyric Acid ◽  
Flow Mode ◽  
Gamma Aminobutyric Acid ◽  
Parboiled Rice ◽  
Head Rice ◽  
Through Flow ◽  
Head Rice Yield

Germinated parboiled rice (GPR) is recognized as a functional food because it is rich in bioactive compounds, especially gamma-aminobutyric acid (GABA). GPR was produced by soaking, incubating, steaming, and then drying using a high-precision hot air dryer. The results indicated that air flow mode and drying temperature had significant effects on the quality of GPR. Drying at higher temperatures and shorter times conserved GABA content. Using through-flow mode decreased drying time and prevented color change. However, a slightly lower percentage of head rice yield was observed. Moreover, using through-flow mode negatively affected the hardness loss after cooking.Keywords: Germinated parboiled rice; Drying mode; Gamma-aminobutyric acid; Head rice yield  

Prediction of Rice Milling Yield and Quality Attributes during Storage Using Regression Analyses

2019 ◽  
Vol 62 (5) ◽  
pp. 1259-1268
Author(s):  
Soraya Shafiekhani ◽  
Jung Ae Lee ◽  
Griffiths G. Atungulu
Keyword(s):  
Hybrid Rice ◽  
Storage Temperature ◽  
Rice Yield ◽  
Storage Conditions ◽  
Milled Rice ◽  
Yield And Quality ◽  
Head Rice ◽  
Rough Rice ◽  
Milling Yield

Abstract. Regression analyses were performed to determine the storage conditions that exhibited the best outcomes for long-grain, hybrid milled rice yield and quality. This study evaluated mold population on rough rice, milled rice discoloration, and head rice yield (HRY) after storage of rough rice in airtight conditions at moisture contents (MCs) of 12.5%, 16%, 19%, and 21% wet basis and temperatures of 10°C, 15°C, 20°C, 27°C, and 40°C at two-week intervals for 12 weeks. The experiment used a popular long-grain hybrid rice cultivar (XL745). Rice lots were procured from fields with and without conventional treatment of the field with fungicide for plant disease management. Field treatment and no field treatment were considered as a block, and a Mann-Whitney test was conducted to determine effect. The response surface method, an extension of second-order polynomial regression, was used to examine optimal treatment conditions. Mold population and milled rice discoloration from a combination of storage conditions were predicted using regression models. The first-order and second-order terms of temperature indicated a nonlinear relationship between temperature and ln(discoloration). The MC was positively associated with ln(discoloration), but the degree of impact may change with temperature because the interaction term was significant. From the model evaluation (R2 and lack-of-fit test), the discoloration level is expected to be 57% (49% to 66% confidence interval) under conditions of 20% MC, 40°C, and nine weeks of storage for samples procured from fungicide-treated rice fields. This discoloration change is substantial compared to the initial discoloration of 9%. At high temperature (40°C) and MC (21%), discoloration started immediately after two weeks of storage. Anaerobic storage conditions impeded mold growth, especially at high storage temperature (40°C). Low mold populations were observed in rice stored at low MC (16%). According to the regression model, the critical storage temperature that may lead to discoloration is between 27°C and 40°C. Pre-harvest fungicide treatment of rice in the field for disease control significantly improved the HRY but had no significant influence on mold population or discoloration. This study suggests a range of storage conditions to prevent losses in milling yield and quality of rice. In addition, the studied storage conditions mimicked the typical conditions for on-farm, in-bin drying and storage in the U.S. Mid-South, especially for the top layers of rice inside the bin, and therefore provide an important reference for growers and rice processors using in-bin structures to manage the quality of long-grain hybrid rice. Keywords: Discoloration, Head rice yield, Mold population, Regression analysis, Rice quality, Rice storage.

scholarly journals Kinetic study, optimization and comparison of sun drying and superheated steam drying of asam gelugor (Garcinia cambogia)

Food Research ◽  
2019 ◽  
Vol 4 (2) ◽  
pp. 396-406
Author(s):  
G.W. Lim ◽  
S. Jafarzadeh ◽  
Norazatul Hanim M.R.
Keyword(s):  
Response Surface Methodology ◽  
Response Surface ◽  
Superheated Steam ◽  
Acid Number ◽  
Drying Process ◽  
Drying Time ◽  
Sun Drying ◽  
Superheated Steam Drying ◽  
Steam Drying

The purposes of present study are to compare the kinetic drying of the G. cambogia through sun drying and superheated steam drying (SSD) method and optimizing the quality of SSD of it through response surface methodology. G. cambogia fruit rinds were dried at temperature of 150°C, 200°C and 250°C. The drying curves were fitted into the mathematical model of Page, Lewis and Henderson-Pabis models. Page model was found to be the best in describing the drying behavior of G. cambogia. Drying rate constant (k) increased as temperature increased and SSD method had overall higher drying rates ranged from 5.929 x 10-5 to 5.861 x 10-4 min-1 than sun drying method which was 4.980 x 10-6 min-1 . Total acid number showed a trend of increased followed by decreased over drying time. superheated steam drying process of G. cambogia fruit rinds was optimized by using response surface methodology employing a central composite design. Drying time and temperature were the factors in optimization while moisture content (wet basis), acid number and lightness (*L) were the response parameters. Experimental results were fitted to a second-order polynomial model and the model fitness and optimal drying condition were determined by regression analysis and analysis of variance. The optimal conditions for superheated steam drying of G. cambogia fruit rinds were identified as 46.60 mins and 150°C with the composite desirability of 0.913. Application of superheated steam drying under controlled conditions resulted in faster drying process and better quality of dried G. cambogia than conventional sun drying technique.

HEAD RICE YIELD OF CROPS HARVESTED BY COMBINE AND HAND AT DIFFERENT RIPENING TIMES IN CAMBODIA

2018 ◽  
Vol 55 (1) ◽  
pp. 132-142 ◽  
Author(s):  
SOM BUNNA ◽  
HOURN SEREYVUTH ◽  
YIM SOMALY ◽  
NGON NGOY ◽  
LOAN MENGSRY ◽  
...  
Keyword(s):  
Rice Yield ◽  
Milling Quality ◽  
Head Rice ◽  
Rough Rice ◽  
Grain Moisture ◽  
General Decline ◽  
Rainfed Lowland ◽  
Head Rice Yield ◽  
Combine Harvester

SUMMARYExperiments were conducted across 2 years to determine the effect of harvesting methods – combine harvester and hand harvesting – and harvest time during ripening on milling quality of long grain rice grown in the rainfed lowland ecosystem in Cambodia. Head rice yield (HRY) was highest when rice was harvested 25 days after flowering and decreased with delay in harvesting at 35 and 45 days after flowering. This was accompanied by a general decline in grain moisture content at harvest, although it was still high at 24–25% at 35 days after flowering. The decline in HRY was associated with increases in fissured grain percentage observed immediately after harvest. Hand harvesting produced 2–6% higher HRY than combine harvesting. Fissured grain in hand harvested crops was lower in year 1, but was similar to combine harvested crops in year 2. Both hand and combine harvested crops were sun-dried but rough rice harvested by combine was dried on plastic sheet and this may have contributed to reduction in HRY. Maximum HRY percentage was only about 44% and the factors contributing to this low HRY were discussed. Harvesting time and methods had no significant effect on grain yield, but the field grain loss during the harvesting operation was 2–5% higher in combine than hand harvesting.

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.

Effect of Soaking Temperature and Steaming Time on the Quality of Parboiled Iranian Paddy Rice

2015 ◽  
Vol 11 (4) ◽  
pp. 547-556 ◽  
Author(s):  
Ebrahim Taghinezhad ◽  
Mohammad Hadi Khoshtaghaza ◽  
Saeid Minaei ◽  
Asefeh Latifi
Keyword(s):  
Rice Yield ◽  
Mean Value ◽  
Rupture Force ◽  
Milling Quality ◽  
Parboiled Rice ◽  
Quality Properties ◽  
Head Rice ◽  
Head Rice Yield ◽  
Color Value

Abstract Iranian paddy (Fajr) is the most popular rice for export and consumption in Iran but it has poor milling yield. To solve this problem, parboiling has been used for improving its milling quality. In this study, the effect of various parboiling conditions (soaking at temperatures of 55–75°C and steaming times for 2–10 min) on some quality properties of Fajr paddy was investigated. After parboiling, the physical properties (degree of milling, head rice yield, lightness and color value) and mechanical properties (rupture force) of parboiled rice were measured. Head rice yield and mean value of rupture force increased significantly (p < 0.05) from 50.10% to 62.11–67.05% and from 108.6 to 128.93–227.30 N, respectively. Also, the color value of parboiled rice increased significantly (p < 0.05) by increasing the length of steaming time. The milling degree of unparboiled rice (17.03%) was significantly (p < 0.05) higher than that of the parboiled rice (15.1–16.9% range). Soaking at 65°C and 4 min steaming time gave the highest values of head rice yield, lightness and rupture force. So, this treatment was found to provide the most desirable quality of Fajr parboiled rice.

scholarly journals The study of quality attributes of parboiled rice during steaming process with revolved sieve

2018 ◽  
Vol 192 ◽  
pp. 03017
Author(s):  
Thatchapol Chungcharoen ◽  
Naruebodee Srisang ◽  
Siriwan Srisang
Keyword(s):  
Thermal Property ◽  
Rice Yield ◽  
Quality Attributes ◽  
Experimental Results ◽  
Parboiled Rice ◽  
Head Rice ◽  
Head Rice Yield ◽  
The Difference ◽  
The Revolution

The steaming process with revolved sieve was studied as a function of steaming time and revolution velocity. The quality of parboiled rice in terms of thermal property, head rice yield and color was investigated and compared to the conventional steaming process such as fixed sieve. The experimental results showed that the steaming process with revolved sieve had advantage over the steaming process with fixed sieve. It led to a steamed sample with higher DG higher head rice yield and lower whiteness value. The required steaming time for a regularity quality by a steaming process with revolved sieve was also shorter. Moreover, the steaming time affected the qualities of parboiled rice. The long steaming time provided the higher DG and head rice yield and lower whiteness value of parboiled rice. Considering revolution velocity, it was found that the revolution velocity did not affect the qualities of parboiled rice. However, the revolution velocity of 5 rpm with steaming time of 5 min provided the difference of quality at each layer.

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