A survey of Alicyclobacillus and its metabolite product spoilage in various juice

To investigate the pollution of Alicyclobacillus and its major metabolite in different types of fruit juices,six types of commercial juice products( 24 samples) were examined in this study. The concentration of guaiacol and2,6- dibromophenol in these juice were detected using solid phase microextraction( SPME) and gas chromatography- mass spectrometry( GC- MS),and the Alicyclobacillus in juice were isolated by using acidified YSG medium( p H = 3.7). The results showed that the detectable rate of 2,6- dibromophenol was 0%( 0 /24),the detectable rate of guaiacol was 33.3%( 8 /24) and the highest concentration of guaiacol reached 26.9 μg / L.Positive rate of Alicyclobacillus in these 24 juice products arrived at 12.5%( 3 /24). Three Alicyclobacillus strains were isolated from the orange juice products with high concentration of guaiacol contamination. The 16 juice samples which guaiacol concentration below the limits of detection,had no identication of Alicyclobacillus. Guaiacol contamination were detected in part of the orange juice,grape juice and peach juice samples in 24 kinds of juice,and the Alicyclobacillus were isolated only in orange juice. The orange juice might be contaminated by Alicyclobacillus and its major metabolite.