Acoustic-mechanical combined technique and electronic nose for the charcterization of crispy bakery products

The crispness of bakery products is controlled by the technological process and by the formulation; in particular is known from the technical literature that emulsifiers and plasticizers, among which some volatile compounds, play an important role in modifying the crispness of dry bakery products. This report will point out the advantages of using the acoustic-mechanical combined technique developed by Stable Micro Systems ( Godalming, U.K.), within a commercial electronic nose to characterize five commercial brands of sliced breads, having a rigid foam structure with a peculiar friability. In order to classify the samples of five commercial brands on the basis of the acoustic and mechanical parameters and of the volatile compounds release, advanced techniques of multivariate statistical analysis were employed to get the maximum information from the proposed instrumental techniques. In particular the results obtained by using an Artificial Neural Network suggest that both the acoustic-mechanical parameters and the electronic nose methodology are efficacious to classify, with high percentages of correct answers, the sliced bread samples in each of the five commercial brands.