The effects of moisture content (8%, 10% and 12%), variety (Tarom and Fajr) and parboiling on milling quality of rice as a function of milling recovery (MR), head rice yield (HRY), degree of milling (DOM) and whiteness were investigated. The parboiled grains was prepared with three soaking temperatures of 25 oC, 50 oC and 75 oC and three steaming times of 10, 15 and 20 min. As a result of parboiling, the increasing rates of MR and HRY values were 7.8% and 14.3% for Tarom and 9.8% and 10.0% for Fajr, respectively, and the decreasing rates for DOM and whiteness were 6.6% and 10.8% for Tarom and 6.8% and 10.5% for Fajr, respectively. Moreover, decreasing moisture content to 8% maximized MR (75.8% for Tarom and 74.3% for Fajr) and HRY (65.8% for Tarom and 57.0% for Fajr) while increasing that to 12% revealed maximum values of DOM (6.1% for Tarom and 6.2% for Fajr) and whiteness (24.8% for Tarom and 28.2% for Fajr).
Abozar NASIRAHMADI, Bagher EMADI, Mohammad Hossein ABBASPOUR-FARD, Hamid AGHAGOLZADE
. Influence of Moisture Content, Variety and Parboiling on Milling Quality of Rice Grains[J]. Rice Science, 2014
, 21(2)
: 116
-122
.
DOI: 10.1016/S1672-6308(13)60169-9
Ali N, Pandya A C. 1974. Basic concept of parboiling of paddy. J Agric Eng Res, 19(2): 111–115.
Andrews S B, Siebenmorgen T J, Mauromoustakos A. 1992. Evaluation of the McGill No. 2 rice miller. J Cereal Chem, 69(1): 35–43.
Banaszek M M, Siebenmoregen T J. 1990. Head rice yield reduction rates caused by moisture. Am Soc Agric Eng, 33(4): 1263–1269.
Bhattacharya S. 1996. Kinetics on colour changes in rice due to parboiling. J Food Eng, 29(1): 99–106.
Courtois F, Faessel M, Bonazzi C. 2010. Assessing breakage and cracks of parboiled rice kernels by image analysis techniques. Food Cont, 21(4): 567–572.
Dors G C, Pinto L A de A, Badiale-Furlong E. 2009. Migration of mycotoxins into rice starchy endosperm during the parboiling process. LWT - Food Sci Tech, 42(1): 433–437.
FAO 2011. Special reports and alerts. Corporate document repository. Available from http://www.fao.org/docrep/013/ al976e/al976e00.htm.
FAOSTAT. 2009 FAO (Food and Agriculture Organisation of the United Nations). Available from http://faostat.fao.org/site/567/ DesktopDefault.aspx?PageID=567#ancor.
Gravois K. 1998. Optimizing selection for rough rice yield, head rice, and total milled rice. Euphytica, 101(2): 151–156.
Gujral H S, Singh J, Sodhi N S, Singh N. 2002. Effect of milling variables on the degree of milling of unparboiled and parboiled rice. Int J Food Prop, 5(1): 193–204.
Iguaz A, Rodríguez M, Vírseda P. 2006. Influence of handling and processing of rough rice on fissures and head rice yields. J Food Eng, 77(4): 803–809.
Imoudu P B, Olufayo A A. 2000. The effect of sun-drying on milling yield and quality of rice. Bioresour Techn, 74(3): 267–269.
Karbassi A, Mehdizadeh Z. 2008. Drying rough rice in a fluidized ded dryer. J Agric Eng Res, 10: 233–241.
Lamberts L, Rombouts I, Brijs K, Gebruers K, Delcour J A. 2008. Impact of parboiling conditions on Maillard precursors and indicators in long-grain rice cultivars. Food Chem, 110(4): 916–922.
Liu K L, Cao X H, Bai Q Y, Wen H B, Gu Z X. 2009. Relationships between physical properties of brown rice and degree of milling and loss of selenium. J Food Eng, 94(1): 69–74.
Liu W, Tao Y, Siebenmorgen T J, Chen H. 1998. Digital image analysis method for rapid measurement of rice degree of milling. Cereal Chem, 75(3): 380–385.
Lv B, Li B, Chen S, Chen J, Zhu B. 2009. Comparison of color techniques to measure the color of parboiled rice. J Cereal Sci, 50(2): 262–265.
Mehdizadeh Z, Zomorodian A. 2009. A study of the effect of solar drying system on rice quality. J Agric Eng Res, 11: 527–534.
Miah M A K, Haque A, Douglass M P, Clarke B. 2002. Parboiling of rice. Part I: Effect of hot soaking time on quality of milled rice. Int J Food Sci Tech, 37(5): 527–537.
Mohapatra D, Bal S. 2007. Effect of degree of milling on specific energy consumption, optical measurements and cooking quality of rice. J Food Eng, 80(1): 119–125.
Ondier G O, Siebenmorgen T J, Mauromoustakos A. 2010. Low-temperature, low-relative humidity drying of rough rice. J Food Eng, 100(3): 545–550.
Pan Z, Thompson J F, Amaratunga K S P, Anderson T, Zheng X. 2005. Effect of cooling methods and milling procedures on the appraisal of rice milling quality. Am Soc Agric Eng, 48(5): 1865?1871.
Pan Z, Amaratunga K S P, Thompson J F. 2007. Relationship between rice sample milling conditions and milling quality. Am Soc Agric Biol Eng, 50(4): 1307–1313.
Pillaiyar P, Sabarathinam P L, Subramaniyan V, Sulochana S. 1996. Parboiling of paddy using thermic fluid. J Food Eng, 27(3): 267–278.
Razavi S M A, Farahmandfar R. 2008. Effect of hulling and milling on the physical properties of rice grains. Int Agrophys, 22: 353–359.
Reid J D, Siebenmorgen T J, Mauromoustakos A. 1998. Factors affecting the slope of head rice yield vs. degree of milling. J Cereal Chem, 75(5): 738–741.
Rice Knowledge Bank. 2012. Rice milling. Available from http:// www.knowledgebank.irri.org/rkb/index.php/rice-milling.
Sareepuang K, Siriamornpun S, Wiset L, Meeso N. 2008. Effect of soaking temperature on physical, chemical and cooking properties of parboiled fragrant rice. World J Agric Sci, 4(4): 409–415.
Soponronnarit S, Nathakaranakule A, Jirajindalert A, Taechapairoj C. 2006. Parboiling brown rice using super heated steam fluidization technique. J Food Eng, 75(3): 423–432.
Sridhar B S, Manohar B. 2003. Hydration kinetics and energy analysis of parboiling indica paddy. Biosyst Eng, 85(2): 173–183.
Sun H, Siebenmorgen T J. 1993. Milling characteristics of various rough rice kernel thickness fractions. Cereal Chem, 70(6): 727–733.
Thompson J F, Knutson J, Jenkins B. 1990. Analysis of variability in ice milling appaisals. Am Soc Agric Biol Eng, 6(6): 194–198.
Yadav B K, Jindal V K. 2008. Changes in head rice yield and whiteness during milling of rough rice (Oryza sativa L.). J Food Eng, 86(1): 113–121.
Yan T Y, Hong J H, Chung J H. 2005. An improved method for the production of white rice with embryo in a vertical mill. Biosyst Eng, 92(3): 317–323.
Zareiforoush H, Komarizadeh M H, Alizadeh M R. 2010. Effects of crop-machine variables on paddy grain damage during handling with an inclined screw auger. Biosyst Eng, 106(3): 234–242.
