Event by Event (E-by-E) fluctuations are considered to be one of the possible indications that a phase transition from ordinary hadronic matter to a plasma of quarks and gluons has occured, as it is expected to happen in ultra-relativistic heavy-ion collisions. During this talk, the results of a study concerning the observabilty and estimation of E-by-E fluctuations in the ALICE experiment at the LHC collider at CERN will be presented. In particular, hadrons' transverse momentum spectra and particle ratios (K/pi) will be discussed. The analysis has relied on the excellent performance of ALICE in terms of particle identification, for which the Time Of Flight detector plays a crucial role.