Abstract
Guar gum-based and starch-based samples were used as typical examples of liquid food to assess three different simple and objective methods for measuring the rheological properties of the samples with commercial thickening agents added. The three methods evaluated were the spring relaxation method with a viscometer, and the tilting test tube and glass ring methods without the use of a viscometer. The usefulness of each method for measuring the rheological properties of the liquid food samples was examined. The spring relaxation method was found to be generally useful, in that it easily allowed the rheological properties, particularly the yield stress, to be obtained with a one-time measurement. The flow time (T) obtained by the tilting test tube method demonstrated a positive correlation with the consistency index (K). The spreading coefficient (R) obtained by the glass ring method demonstrated of negative correlation with the yield stress from the spring relaxation.
