Journal of Applied Microbiology, Vol.126, No.2, 545-554, 2019
Monitoring of assertive Lactobacillus sakei and Lactobacillus curvatus strains using an industrial ring trial experiment
Aims In a previous study, we used a 5-day fermenting sausage model to characterize assertiveness of Lactobacillus curvatus and Lactobacillus sakei starter strains towards employ autochthonous contaminants. In this work, we probed those findings and their transferability to real sausage fermentation including the drying process in an industrial ring trial experiment. Methods and Results Raw fermented sausages ('salami') were produced with three L. curvatus and four L. sakei strains as starter cultures in cooperation with three manufacturers from Germany. We monitored pH, water activity and microbiota dynamics at strain level over a total fermentation and ripening time of 21 days by MALDI-TOF-MS identification of isolates. The principal behaviour of the strains in real sausage fermentations was the same as that one observed in the 5-day model system delineating single strain assertiveness of a bacteriocin producer from co-dominance of strains. Conclusions The water activity decrease, which is concomitant with the sausage ripening process has only limited impact on the assertiveness and survival of the starter strains. Significance and Impact of the Study Results of a 5-day model can provide insight in the assertiveness of a specific starter strain in sausage fermentation.
Keywords:assertiveness;lactic acid bacteria;Lactobacillus curvatus;Lactobacillus sakei;MALDI-TOF-MS;raw sausage fermentation