Composition of Corn Steep Water during Steeping

Abstract

Corn wet-milling generates large volumes of corn steep water, which is composed of kernel extractives, microbes (principally lactobacilli), numerous products of fermentation processes, and dissolved SO2. In order to understand better the process of steeping and the potential uses of corn steep water, its composition was analyzed and compared at various times during the steeping from four different industrial processes. Of particular interest were the analyses of corn steep water for carbohydrates, amino acids, polypeptides, fatty acids, and other organic compounds, hydrolytic enzymes, heavy metals, and inorganic ions. This study, together with an earlier analysis of corn steep water for myo-inositol phosphates (Hull and Montgomery, 1995), provides a basis for informed judgment of the nutritional and biotechnological value of corn steep water, an abundant byproduct of the corn wet-milling industry. Keywords: Corn steep water; compositional analysis; steeping