Effect of high shear stress on microbial viability

Hélène Lange (1) , Patricia Taillandier (1) , Jean-Pierre Riba (1)

1 LGC - Laboratoire de Génie Chimique

Escherichia coli and Saccharomyces cerevisiae suspensions were submitted to controlled shear stress. Above a threshold value shear stress induced a decrease in micro-organism viability. The threshold of shear stress efficiency depended on the micro-organisms, being between 1292Pa and 2770 Pa for S cerevisiae, and about 1250 Pa for E coli. Above 1810 Pa, Ecoli cells were disrupted whereas the S cerevisiae cells remained intact. The higher the cellular concentration, the greater the rate of decrease in viability. Viability loss was influenced by the number of passages through the experimental shear stress device and by exposure time.

Mots clés: Shear stress; Viability; Saccharomyces cerevisiae; Escherichia coli

Domaines: Génie chimique; Génie des procédés

Hélène Lange, Patricia Taillandier, Jean-Pierre Riba. Effect of high shear stress on microbial viability. Journal of Chemical Technology and Biotechnology, 2001, 76 (5), pp.501-505. ⟨10.1002/jctb.401⟩. ⟨hal-02143250⟩