RELATIONSHIPS BETWEEN SENSORY PROFILE PARAMETERS AND FUNDAMENTAL MECHANICAL PARAMETERS FOR RAW POTATOES, MELONS AND APPLES1

Abstract

ABSTRACTRatings by a trained texture profile panel were compared with the mechanical properties (shear stress at structural failure, normal strain to failure and apparent elastic modulus) determined in torsion and uniaxial compression for apple, melon and Irish potato flesh.Results indicated that, for melon and potato flesh, the structural failure stress levels were more frequent and significant indicators of sensory note magnitudes than the modulus values. The reverse was true for apple flesh. Of the sensory notes, moisture release correlated most consistently with the mechanical properties.Melon flesh failed in uniaxial compression by widespread crushing rather than along a failure plane. Correlation of the mechanical failure stress with the first bite sensory notes dominated in this case. The structural failure of potato flesh in uniaxial compression generally occurred along a single plane of maximum shear stress which left two essentially intact pieces of specimen. First bite and mastication sensory notes for potato flesh correlated with shear stress at failure about equally well. The structural failure of apple tissue in uniaxial compression was caused by general compression failure with many fragmented pieces of tissue remaining. Apple flesh produced the most frequent correlations of both first bite and mastication texture notes with the instrumental modulus and failure values.