The predominant microbiological populations in ready-to-eat salads are comprised of the psy- chrotrophs Pseudomonas spp. and Erwinia spp., in addition to lactic acid bacteria including Leu- conostoc mesenteroides (Clark and Burki, 1972; Willocx et al., 1993). Pectolytic strains of Pseu- domonas have been reported to cause vegetable deterioration during storage (Denis and Picoche, 1986; Brocklehurst et al., 1987; Carlin et al., 1990)