Publication no. C-2004-0126-06R |  VIEW ARTICLE

Ozone-Aided Corn Steeping Process.

Roger Ruan (1,2,4), Hanwu Lei (3), Paul Chen (3), Shaobo Deng (3), Xiangyang Lin (4), Yuhong Li (3), William Wilcke (3), and Gary Fulcher (5). (1) Biosystems and Agricultural Engineering, and Food Science and Nutrition, University of Minnesota, 1390 Eckles Ave., St., Paul, MN 55108. (2) Corresponding author. E-mail: <ruanx001@umn.edu> (3) Biosystems and Agricultural Engineering, University of Minnesota, St., Paul, MN 55108. (4) MOE Key Laboratory of Food Science, Nanchang University, Jiangxi 330047, China. (5) Food Science and Nutrition, University of Minnesota, St. Paul, MN 55108. Cereal Chem. 81(2):182-187. Accepted September 23, 2003. Copyright 2004 American Association of Cereal Chemists, Inc.

The present research evaluated the feasibility of using ozone (O(3)) to replace sulfur dioxide (SO(2)) in corn steeping. Traditionally, steep water contains 0.1-0.2% sulfur dioxide to promote starch-protein separation and high starch yields, and to control microbial growth. However, residual SO(2) in starch products affects product quality and jeopardizes the “organic products” claims. Also, SO(2) discharged to the environment pollutes water and air. Ozone is a strong oxidant and disinfectant with a capability to control the growth of putrefactive microorganisms in steeping systems, and to break down the endosperm protein matrix and, hence, improve starch release. This study demonstrates that an ozone-aided steeping (OAS) process had starch yields as high as conventional SO(2) steeping. OAS processes can be conducted at a lower temperature (20°C vs. 50°C) and for shorter times (36 hr vs. 48 hr) than the conventional SO(2) processes, suggesting significant energy savings and increased productivity. We have found that the timing of ozone application is of great importance to the performance of the OAS process.