There is an ongoing debate about the frequency content of the gastric electrical signals, acquired both serosally or cutaneously. Changes that occur in the frequency content of the serosal electrical activity during gastric motility are not yet fully understood. We present here the Continuous Wavelet Transform Analysis (CWTA) as a tool to obtain the time-frequency distribution of the serosal signal to monitor such changes. The results obtained by CWTA are also compared with two other methods, namely the Autoregressive (AR) model and the bispectrum based method. Our aim is to validate that the CWTA method achieves a higher level of accuracy in evaluating and tracking these changes in the serosal data compared to conventional methods.