FIG. 5.

Principal component analysis of EMA-PCR data to study the survival of C. jejuni on chicken breasts and legs. The samples spiked with C. jejuni C-523 or C-524 were stored in a modified or normal atmosphere as described in Materials and Methods. White and black columns represent storage at 5 and 12°C, respectively. Principal component analysis was performed on the EMA-PCR data after 1 h, 7 days, and 19 days of storage for each condition tested. The first principal component explained 79% of the variance in the data. The input was the average signal for four measurements for each of 48 independently packed and spiked samples. NORM, normal atmosphere; MOD, modified atmosphere. The averages for three independent replicates for each condition tested were used for principal component analysis.