On the application of chemometrics for the study of acoustic-mechanical properties of crispy bakery products

Crispness is a salient textural property for most fresh and dry food products. Its loss, due to the adsorption of moisture, is a major cause of rejection by consumer. Crispness is related to food structure and its mechanical properties by the capability to generate an appropriate sound during mastication and to dampen or amplify this sound. The perception of crispness is therefore a simultaneous response to mechanical and acoustic stimuli. It is known that an objective instrumental acoustic-mechanical combined technique for texture analysis of food products can supply useful information on the structure of crispy products, but new methods to interpret the relevant information content of the instrumental response are required, in order to integrate traditional data analysis. Multivariate analysis appears ideal for studying this kind of data and to our knowledge has never been applied on combined acoustic-mechanical measurements. In this work, acoustic-mechanical properties of sliced toasted breads were analysed by means of chemometric tools, such as Principal Component Analysis and Discriminant Analysis. Final results proved that multivariate analysis is able to extract relevant information and offer an easy and promising approach for the interpretation of instrumental food texture attributes.