Measurement of crispness in food products using acoustic-mechanical techniques: a literature review

There are many interesting research topics in the physics of cooking. Research on crispness has increased over the past years due to rising consumer demand for crisp food products. Mechanical tests (Vincent, 1998; Ross, 1999; Ross and Scanlon, 2004) have failed to produce significant correlation with sensory crispness and are limited by the geometry and composition of the food sample (Saeleaw and Schleining, 2011). Recently, there has been a particular focus on the measurement of crispness using acoustic-mechanical parameters. Studies on crusted food products with a high-moisture core have proved particularly inconclusive. Developing both a better understanding and acoustic-mechanical measure of crispness across all food types is critical to improving the correlation of instrumental measurement with the sensory perception of food texture. This review assesses studies that have contributed to the development thus far; the first part summarizes research on crispness of solid, brittle food products and the second focuses on that of crusted food products with a high-moisture core.