Fig. 9: Multivariate classifications of IR spectral datasets of L. parabuchneri biofilms via principal component analysis.

a Scores plot of the classified spectral data recorded after 24, 48, 72, and 96 h via PCA revealing that the obtained spectra clearly cluster along the time axis and that the recorded IR spectra unambiguously identify the maturation stage of the biofilm; b loadings of the two PCs explaining >98% of the total variance.