Effect of Germination Time and Extrusion Temperature on Properties of Germinated Brown Rice

발아시간과 압출성형온도가 발아현미의 성질에 미치는 영향

  • Published : 2007.05.30


In order to develop a novel food utilization of germinated brown rice, physicochemical properties of germinated brown rice and its extrudates were investigated. The physical characteristics, the paste viscosity, and the anti-oxidation activity were analyzed. Brown rice was soaked for 10 hr and germinated for 24 and 48 hr at $30^{\circ}C$. Extrusion conditions of brown rice and germinated brown rice were barrel temperature at 100 and $120^{\circ}C$ and moisture content at 20%. The expansion ratio increased with the increase in germination time. It increased at barrel temperature of $100^{\circ}C$, and decreased at $120^{\circ}C$. The bulk density showed negative corporations with the expansion ratio. The paste viscosity of germinated brown rice was decreased with the increase in the germination time. However the paste viscosity of extrudates was lower as barrel temperature increased. Content of polyphenolic compound in extrudates was increased by increasing germination time and barrel temperature.

본 연구는 식미가 뛰어난 압출성형 발아현미 식품소재 개발에 대한 기초 연구로서 원료 발아현미와 압출성형 발아현미의 물리적 특성, 페이스트 점도, 색도 및 항산화성 등을 비교 검토하였다. 발아는 24 hr, 48 hr 동안 $30^{\circ}C$에서 실시하였으며, 현미 및 24시간, 48시간 발아현미를 시료로 하였다. 쌍축 동방향 압출성형기를 사용하여 수분함량 20%, 배럴온도는 $100^{\circ}C$$120^{\circ}C$로 조절하여 압출성형하였다. 압출성형물의 발아시간에 따른 팽화율은 배럴온도 $100^{\circ}C$에서는 증가, $120^{\circ}C$에서는 감소하였으며, 밀도는 $100^{\circ}C$에서 감소, $120^{\circ}C$에서 증가하여 팽화율과는 음의 상관관계를 나타내었다. 발아시간에 따른 파괴력은 배럴온도 $100^{\circ}C$에서는 증가하였으며, $120^{\circ}C$에서는 감소하였다. 페이스트 점도는 발아현미는 발아시간에 따라 페이스트 점도가 감소하였으나, 압출성형물은 발아시간에 관계없이 배럴온도 $100^{\circ}C$$120^{\circ}C$보다 약간 높은 페이스트 점도를 나타내었다. 색도의 명도는 압출성형물간의 유의적 차이는 나타나지 않았으며 갈색도는 배럴온도 $100^{\circ}C$에서는 24 hr 발아현미가, $120^{\circ}C$에서는 48 hr 발아현미가 가장 높은 값을 나타내었다. 환원당 함량은 발아시간이 증가할수록 증가하였다. $\gamma$-Oryzanol의 함량은 발아시간이 증가할수록 약간 감소하였으며, 압출성형에서는 배럴 온도가 증가할수록 감소하는 경향을 나타내었다. Polyphenolic compound 함량은 발아시간이 증가할수록 감소하는 것으로 나타났으나 압출성형물에서는 발아시간이 증가하고 배럴 온도가 증가할수록 polyphenolic compound 함량은 증가하는 것으로 나타났다.


  1. Juliano BO, Bechtel DB. 1985. Rice Chemistry and Technology. The American Association of Cereal Chemists, Inc., Minnesota. p 17-58
  2. Kim SL, Son YK, Rok J, Hur HS. 2001. Effect of germination condition and drying methods on physicochemical properties of germinated brown rice. Korean J Crop Sci 46: 221-228
  3. Lee HJ, Byun SM, Kim HS. 1988. Studies of the dietary fiber of brown rice and milled rice. Korean J Food Sci Technol 20: 576-580
  4. Kum JS, Choi SK, Lee HY, Park JD, Park HJ. 2004. Physicochemical properties of germinated brown rice. Korean J Food Preserv 11: 182-188
  5. Jang SS. 1988. Method of germinating with brown rice. Korea Patent No. 1988- 0247686
  6. Oh SS. 2002. Study on nutritional properties of sprouting brown rice. MS Thesis. Kongju National University, Gongju, Korea
  7. Anderson RA, Conway HF, Pfeifer VF, Griffin EL. 1969. Gelatinization of corn grits by roll and extrusion-cooking. Cereal Sci Today 14: 4-7, 11-12
  8. Wilton CT, Bengera I, Smith OB, Rokey GJ. 1984. Energy aspects in extrusion cooking of starches and flours. In Thermal Processing and Quality of Foods. Zeuthen P, Cheftel JC, Eriksson C, Jul M, Linko P, Vos G, eds. Elsevier Applied Science Publ., London. p 180-184
  9. Kim SN, Son YK, Son JR, Hur HS. 2001. Effect of germination condition and drying methods on physicochemical properties of sprouted brown rice. Korean J Crop Sci 46: 221-228
  10. AOAC. 2005. Official Methods of Analysis. 18th ed. Method 925.10. Association of Official Analytical Communities, Arlington, VA, USA
  11. Miller GL. 1959. Use of dinitrosalicylic acid regent for determination of reducing sugar. Anal Chem 31: 426-428
  12. Deffenbaugh LB, Walker CE. 1989. Use of the rapid- visco-analyzer to measure starch pasting properties. Starch/ Starke 41: 461-467
  13. Deffenbaugh LB, Walker CE. 1989. Comparison of starch pasting properties in the Brabender viscoamylograph and rapid visco-analyzer. Cereal Chem 66: 493-499
  14. Tian S, Nakamura K, Cui T, Kayahara H. 2005. High-per- formance liquid chromatographic determination of phenolic compounds in rice. J Chromatogr A 1063: 121-128
  15. Perretti G, Miniati E, Montanari L, Fantozzi P. 2003. Improving the value of rice by-products by SFE. J Supercrit Fluids 26: 63-71
  16. Gutfinger T. 1981. Polyphenols in olive oils. J Am Oil Chem Soc 58: 966-968
  17. Bhattacharya B, Choudhury GS. 1994. Twin-screw extrusion of rice flour: effect of extruder length-to-diameter ratio and barrel temperature on extrusion parameters and product characteristics. J Food Process Preserv 18: 389-406
  18. Chinnaswamy R, Hanna MA. 1990. Macromolecular and functional properties of native and extrusion cooked corn starch. Cereal Chem 67: 490-499
  19. Jackson DS, Gomez MH, Waniska RD, Rooney LW. 1990. Effects of single-screw extrusion cooking on starch as measured by aqueous high-performance size-exclusion chromatography. Cereal Chem 67: 529-532
  20. Keitaro S, Hiroshi O, Tomoya O, Sumiko N, Ken'ichi O. 2003. Development of a novel food material using germinated brown rice by twin-screw extrusion. Nippon Shokuhin Kagaku Kogaku Kaishi 50: 474-482
  21. EL-Dash AA, Gonsaless R, Ciol M. 1984. Response surface methodology in the control of thermoplastic extrusion of starch. In Extrusion Cooking Technology. Jowitt R, ed. Elsevier Applied Science Publishers, New York. p 51-74
  22. Kim DH. 2004. Food Chemistry. Tamgudang, Seoul, Korea. p 416-421
  23. Yuji Y, Keitaro S, Hiroshi O, Tomoya O, Katsuhiko H, Kenichi O. 2004. Preparation of co-extruded flours using germinated brown rice and barley and its antihypertensive effect. Nippon Shokuhin Kagaku Kogaku Kaishi 51: 592- 603

Cited by

  1. The Impact of Cooking on the Antioxidative and Antigenotoxic Effects of Rice vol.42, pp.9, 2013,
  2. Total Phenolic Content and Antioxidant Activity of Extruded Brown Rice vol.15, pp.2, 2012,
  3. Effect of Presoaking on Textural, Thermal, and Digestive Properties of Cooked Brown Rice vol.86, pp.1, 2009,
  4. Effects of Extrusion Conditions on the Physicochemical Properties of Extruded Red Ginseng vol.17, pp.3, 2012,
  5. Quality Properties of Sulgi with Different Mixed Ratio of Brown Rice Flour and Germinated Brown Rice Flour vol.29, pp.5, 2013,