  2001 AACC Annual Meeting Charlotte, North Carolina October 14-18, 2001 Charlotte Convention Center  |
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Endosperm lipids in dried and processed corn. T. BETA (1), K. Seetharaman (2), C. J. Bern (3), and P. J. White (1). (1) Department of Food Science and Human Nutrition, Iowa State University, Ames, IA 50011; (2) Department of Food Science, Pennsylvania State University, University Park, PA 16802; (3) Agricultural and Biosystems Engineering Dept., Iowa State University.
To determine the changes in endosperm lipids and the potential impact of the lipids on processing quality, three corn types (normal, waxy and high-amylose) were harvested and dried at three different temperatures (ambient, 150 and 200°F) prior to storage for four months. Whole kernel lipid content was determined, whole endosperm was isolated and the lipids extracted. Dry milling was performed using a simple degerminator and five fractions were collected by sieving and aspiration. Whole kernel lipid content was 3.1% for normal corn, 3.4% for waxy corn and 4.4% for high-amylose corn. Endosperm lipids totaled 0.4% for normal corn, 0.7% for waxy corn and 0.8% for high-amylose corn. Drying corn at 150 and 200°F significantly reduced lipid quantity extracted from the endosperm. The lipid percentages of the dry-milled fractions in all three corn types dried under ambient conditions varied from 0.7% to 2.9%, indicating a significant level of germ contamination. High amylose corn had the greatest amount of lipids in the dry milled fractions. The "greater than 7 fraction" had the least lipid content among the five fractions (>5, >7, >12, >30 and flour) for all corn types. Differences in processing characteristics of normal, waxy and high-amylose corn dried at different temperatures suggest the need for optimization of handling and tempering techniques prior to milling for each corn type.
Copyright 2001
The American Association of Cereal Chemists