Inverse analysis of water profile in starch by non-contact photopyroelectric method

The photopyroelectric (PPE) method in a noncontact configuration was propos ed to study water migration in starch sheets used for biodegradable packagi ng. A 1-D theoretical model was developed, allowing the study of samples ha ving a water profile characterized by an arbitrary continuous function. An experimental setup was designed or this purpose which included the choice o f excitation source, detection of signals, signal and data processing, and cells for conditioning the samples. We report here the development of an in version procedure allowing for the determination of the parameters that inf luence the PPE signal. This procedure led to the optimization of experiment al conditions in order to identify the parameters related to the water prof ile in the sample, and to monitor the dynamics of the process.