With the purpose of avoiding experimental errors in the determination
of the moment where the spectra begin to change as
compared to the ‘‘zero time’’ sample, Quality Control tool of the
EZ Omnic7.4.127 software was used. This tool allows a rapid determination
of induction times without processing spectra. The fingerprint
region (1500–650 cm1
) of the IR spectra was used to
compare the fresh oil with the other samples. The critical value
of correspondence was 95%.