Aims: To evaluate Fourier transform infrared (FT-IR) techniques for detecting, quantifying, and differentiating viable and heat-treated cells of Salmonella enterica serovars from chicken breast. Methods and Results: Salmonella enterica serovars were captured from inoculated chicken breast by filtration and immunomagnetic separation (IMS) prior to spectral collection using an FT-IR spectrometer and IR microscopy. The detection limits, based on amide II peak area (1589 to 1493 cm(-1)), for the Filtration-FT-IR and IMS-FT-IR methods were 10(6) and 10(4) CFU g(-1), respectively. The bacteria were detectable after 6 h of culture enrichment during a sensitivity experiment with lower initial inoculum of 10(1) CFU g(-1). Canonical variate analysis differentiated experimental from control spectra at a level of 10(3) CFU g(-1). Partial least squares models were established for the quantification of Salm. enterica from chicken breast using Filtration-FT-IR (R-2 >= 0.95, RMSEC <= 0.62) and IMS-FT-IR (R-2 >= 0.80, RMSEC <= 1.61) methods. Filtration-FT-IR was also used to detect and quantify live Salm. enterica in the presence of heat-treated cells with R-2 = 0.996, and this approach was comparable to the results of a commercial stain (BacLight(TM); R-2 = 0.998). Discriminant and canonical variate analyses of the spectra differentiated live and dead cells of different serovars of Salm. enterica. Conclusions: FT-IR analysis coupled with separation methods is useful for the rapid detection and differentiation of Salm. enterica separated from chicken. Significance and Impact of the Study: FT-IR-based methods are faster than traditional microbiological methods and can be used for the detection of live and dead bacteria from complex foods.