Volume 7, Issue 2 (February 2010)

    Characterization of Corn Grains for Dry-Grind Ethanol Production

    (Received 28 May 2009; accepted 13 November 2009)

    Published Online: 2009

    CODEN: JAIOAD

      Format Pages Price  
    PDF Version 10 $25   ADD TO CART


    Abstract

    The objectives of this study were to understand how the composition of corn kernels and starch structure affected the enzyme hydrolysis of starch in dry-grind corn and the ethanol yield from yeast fermentation. Four selected corn inbred lines were used in this study. Starch in uncooked dry-grind corn samples showed greater enzyme digestibility than did the uncooked starch isolated from the same source by wet-milling process. The greater digestibility of starch in uncooked dry-grind corn correlated with a physical damage of starch granules. In contrast, starch in cooked dry-grind corn samples displayed less enzyme digestibility than did the cooked isolated starch. The difference could be attributed to interference caused by non-starch components in the dry-grind corn. The entrapment of starch in protein matrix and the formation of amylose-lipid helical complexes and/or retrograded starch may decrease the enzyme digestibility of starch in cooked dry-grind corn. Lab-scale ethanol production showed that ethanol yield after 72 h fermentation of the four corn inbred lines ranged between 34.3 and 38.0 g ethanol/100 g dry-grind corn. The conversion efficiency at 72 h of fermentation ranged between 86.8 % and 90.3 % of the theoretical ethanol yield. The highest ethanol yield was found in the corn line containing the largest starch content and the smallest amounts of lipid and protein.


    Author Information:

    Srichuwong, Sathaporn
    Dept. of Food Science and Human Nutrition, Iowa State Univ., Ames, IA

    Gutesa, Jelena
    Dept. of Food Science and Human Nutrition, Iowa State Univ., Ames, IA

    Blanco, Michael
    Plant Introduction Research Unit, USDA-ARSDept. of Agronomy, Iowa State Univ., Ames, IA

    Duvick, Susan A.
    Plant Introduction Research Unit, USDA-ARSDept. of Agronomy, Iowa State Univ., Ames, IA

    Gardner, Candice
    Plant Introduction Research Unit, USDA-ARSDept. of Agronomy, Iowa State Univ., Ames, IA

    Jane, Jay-Lin
    Dept. of Food Science and Human Nutrition, Iowa State Univ., Ames, IA


    Stock #: JAI102568

    ISSN: 1546-962X

    DOI: 10.1520/JAI102568

    ASTM International is a member of CrossRef.

    Author
    Title Characterization of Corn Grains for Dry-Grind Ethanol Production
    Symposium , 0000-00-00
    Committee E48