Publication no. C-2004-1028-07R |  VIEW ARTICLE

Effects of Protein Content and Composition on White Noodle Making Quality: Color (1).

Chun Wang (2,3), Miklos I. P. Kovacs (1,4), D. B. Fowler (5), and Richard Holley (2). (1) Agriculture and Agri-Food Canada, Cereal Research Centre, 195 Dafoe Road, Winnipeg, MB, Canada R3T 2M9. Contribution No. 1873. (2) Department of Food Science, University of Manitoba, MB, Canada R3T 2N2. (3) Present Address: Zhengzhou Institute of Technology, 140 Songshan Road, Zhengzhou, Henan, P. R. China, 450052. (4) Corresponding author. Phone: 204-983-1385. Fax: 204-983-4604. E-mail: <MiklosKovacs@mts.net> (5) Dept. Crop Science, University of Saskatchewan, Saskatoon, SK, Canada S7N 5A8. Cereal Chem. 81(6):777-784. Accepted July 26, 2004. Copyright 2004 American Association of Cereal Chemists, Inc.

Wheat cultivars, representing three winter and three spring wheats were grown in western Canada with six levels of nitrogen fertilizer and flours were prepared from them with an extraction rate of 65%. Using a chromameter, flour color and the color of uncooked white noodle sheets made from these flours with different resting times were assessed. The cooked noodle sheet color was also assessed. While protein content initially declined with added nitrogen and increased with further nitrogen addition, brightness (L*) of flour decreased and redness (a*) and yellowness (b*) increased. Positive correlation coefficients of flour brightness with particle size index (PSI) were also observed. Flour redness (a*) and yellowness (b*) were also affected by flour moisture content, whereas L* values were not significantly correlated with moisture contents. For the uncooked white noodle sheet, as protein content increased brightness decreased but there was an increase in a* and b* values. Thus, the L* value for noodle sheets was negatively correlated with the a* and b* values. The percentages of monomeric protein and soluble glutenin in flour were equal to or better than protein content in relation to most noodle sheet color characters. Uncooked noodle sheet brightness decreased, while redness and yellowness increased with rest time. In general, uncooked white noodle sheets prepared from different wheat flours can be ranked in terms of brightness and yellowness within each level of nitrogen fertilization.