Publication no. C-2002-1001-03R |  VIEW ARTICLE

Understanding and Modeling the Processing-Mechanical Property Relationship of Bread Crumb Assessed by Indentation.

Zhiqiang Liu (1) and Martin G. Scanlon (1,2). (1) Department of Food Science, University of Manitoba, Winnipeg, MB, Canada R3T 2N2. (2) Corresponding author. E-mail: <scanlon@cc.umanitoba.ca> Phone: 204-474-6480. Fax: 204-474-7630. Cereal Chem. 79(6):763-767. Accepted May 31, 2002. Copyright 2002 American Association of Cereal Chemists, Inc.

Measuring fundamental mechanical parameters such as Young’s modulus and critical stress is a straightforward and valid approach to evaluating the physical texture of breadcrumb. The objectives of this study were to evaluate whether such fundamental mechanical properties could be measured by indentation techniques such as the AACC crumb firmness method, and then to alter breadmaking conditions so as to model the relationship between these indentation mechanical properties as a function of crumb moisture content and crumb density. Bread was baked according to a short dough process using Canadian western red spring (CWRS) wheat flour. Factors considered in the design of experiments were proofing time, water absorption, crosshead speed, and indenter diameter. Young’s modulus and critical stress, measured with 12- and 20-mm cylindrical indenters, were well covalidated with those obtained from a standard compression test. With increases in proofing time and water absorption, a more porous and compliant bread texture led to decreasing Young’s modulus and critical stress. Our results revealed a good mapping of mechanical properties to crumb moisture content and density that were correlated to breadmaking conditions, thus permitting more precise prediction of the mechanical properties that determine bread texture.