Characteristics and Yield of Jochung Processed by Different Preparation Methods

제조 방법에 따른 쌀 조청의 특성 및 수율

  • Received : 2014.03.28
  • Accepted : 2014.05.30
  • Published : 2014.06.30


This study was performed to increase the yield and to reduce the processing times for the preparation to improve the productivity and quality of rice jochung, a traditional food in Korea. In order to evaluate the quality characteristics and yield of jochung, the viscosity, color value, mineral contents and the sensory evaluation were measured. Jochung is prepared from steamed rice (STR), wet-milled rice flour (WRF) and dry-milled rice flour (DRF) by processing methods of rice and reacting times (6 hours or 13 hours) of liquefaction and saccharification. There is commonly added liquefying enzyme for rice liquefaction (0.4%/10 kg rice, at $85{\sim}90^{\circ}C$ for 1 hour or 4 hours) and saccharogenic enzyme with malt (2.5% or 4.5%/10 kg rice, at $56{\sim}60^{\circ}C$ for 5 hours or 9 hours). The inner structural properties of WRF showed the more distinct shape regular structure of uncombined starch particles but the DRF closely maintained particles of rice flour observed by SEM. If processing times for liquefation and saccharification were reduced from 13 hours to 6 hours, the yield of jochungs prepared with WRF increased 8%, the DRF 7%, and the STR 3% respectively and the sensory evaluation as well as color values and overall desirability received high scores. The viscosity, color a and b values of jochung processed with WRF for 6 hours were lower than that processed for 13 hours. The viscosity and color a, b value and Ca content were decreased in the jochung processed with WRF or DRF for 6 hours, but Mg, P and K were increased than that of STR. Jochung processed by 0.4% liquefying enzyme and 2.5% malt with WRF for 6 hours will increase the yield, save manufacturing times and costs and will thereby enable cost-effective techniques.


jochung;wet-milled rice flour;time reduction;yield


  1. Kim SS, Kim YJ. 1995. Effect of moisture content of paddy on properties of rice flour. Korean J Food Sci Technol 27:690-696
  2. Lee HS, Cho Y. 2006. chapter 6 cooking of cereals. In: Cooking Principles. pp.62-63. Gyomunsa Publishers Ltd.
  3. Lee JE, Choi YH, Cho MG, Park SY, Kim EM. 2012. Characteristics of jochung by wet milled rice flour and steamed rice. Korean J Food & Nutr 25:637-643
  4. Lee KH. 1999. The method of jochung preparation with fruits. Korean Patent 1999-0062-369
  5. Lee MK, Kim JO, Shin MS. 2004. Properties of nonwaxy rice flours with different soaking time and particle sizes. Korean J Food Sci Technol 36:268-275
  6. Park JH. 2009. Improvement of saccharification process through analysis of traditional jochung manufacturing process. MS Thesis, Kongju National Univ. Kongju. Korea
  7. Park JS, Na HS. 2005. Quality characteristics of jochung containing various level of Letinus edodes powder. Korean J Food Sci Technol 37:768-775
  8. RDA, National Academy of Agriculturals Science. 2011. 8th Revision Standard Food Composition Table. pp.82-87. Kyowmunsa Publishers Ltd
  9. Yang HJ, Ryu GH. 2010. Preparation and characterization of jochung a grain syrup, with apple. J Korean Soc Food Sci Nutr 39:132-137
  10. Yang YH, Oh SH, Kim MR. 2007. Effect of grain size on the physicochemical properties of rice porridge. Korean J Food Cookery Sci 23:314-320
  11. AOAC. 1990. Official Methods of Analysis. 15th ed., pp.84-88. Association of Official Analytical Chemists. Washington, D.C, USA
  12. Choi YH, Lee JE, Kim EM, Park SY. 2012. Quality changes of steamed rice bread with addition of active gluten and rice nuruk. Korean J Food & Nutr 25:253-258
  13. Chung HJ, Park HN, Chu YR, Jeon IS, Kang YS. 2010. Quality characteristics and antioxidant activity of syrup added with Maca (Lepidium meyenii) extract. Korean J Food Preserv 17:236-242
  14. Jung SC. 2010. Dining Table Have a Way. pp.136-149. Moseag Publishers Ltd.
  15. Kim JN, Shin WS. 2009. Physical and sensory properties of chiffon cake made with rice flour. Korean J Food Sci Technol 41:69-76
  16. Kim KH, Park SH. 1995. Liquefaction and saccharification of tapioka starch for fuel ethanol production. Korean J Biotechnol Bioeng 10:304-316
  17. Kim KW, Min KC, Yoo YG, Wei SU, Cho DM. 2007. Food Chemistry pp.56. Kwangmunggak Publishers Ltd.

Cited by

  1. Study on Utilization and Perception of Jochung vol.25, pp.6, 2015,
  2. Quality Characteristics of Gastrodia elata Extract Glutinous Rice Porridge Jochung and Principal Component Analysis of Antioxidant Activity vol.25, pp.6, 2015,


Supported by : 국립농업과학원