The study of combustion requires description of the thermochemistry of elementary reactions. Typically a detailed chemical kinetic description of hydrocarbons reaction with air involves dozens of species, hundreds of elementary reactions and timescales which vary up to nine orders of magnitude. These characteristics imply that the numerical integration of the detailed thermochemical evolution equations is a hard work. This work studies and implements a technique to reduce the integration time of the system of equations governing thermochemistry. The technique used is in situ adaptive tabulation, which has been shown to be very eficient on the treatment of complex reaction thermochemistry.