DEVELOPMENT OF AN ACOUSTIC MEASUREMENT SYSTEM FOR ANALYZING CRISPINESS DURING MECHANICAL AND SENSORY TESTING

The objective of this study was to develop an acoustic measurement system for analyzing crispiness and correlate its results with sensory evaluation. Four biscuits (Crackerbread, Table Water, Rich Tea and Shortbread) were punctured using an Instron Universal Testing Machine. The force-displacement and sound amplitude-time signals were simultaneously recorded during puncturing. The acoustic recording system was also used to capture sound emitted during sensory evaluation. From the force-displacement signal, the number of peaks, maximum force, curve length, work, crispiness work and initial slope were extracted. From the sound data, the maximum sound pressure, number of sound peaks, sound curve length and area under amplitude-time curve were obtained. The number of force and sound peaks, spatial ruptures, sound curve length and area under the sound curve correlated well (R2 > 0.77) with sensory crispiness data. An acoustic measurement system for analyzing crispiness was developed which can be used with most food texture-analyzing instruments and during sensory evaluation. PRACTICAL APPLICATIONS The method proposed in this study provides an acoustic system for capturing and analyzing sound data during mechanical testing of crispy foods using Instron Universal Testing Machine. The system is designed in such a way that it can be used as an attachment with any food texture-analyzing system. In addition, the acoustic system can be used independently from texture-analyzing instrument especially during sensory evaluation.