Enterococcus faecium in artisanal ripening cheese: technological and safety aspects

Abstract

The aims of this work were to identify and characterize for some important technological properties of the E. faecium throughout the ripening process of cheese. The study involved evaluating the technological potential of six isolates of E. faecium (EFM55, EFM67, EFM9A, EFM16A, EFM19A and EFM44) from artisanal cheeses as their probiotic characteristics and technological perspective. Concerning the antimicrobial sensibility, 71% of the E. faecium tested were sensitive to all antimicrobials. No other medicine inhibited the active of E. faecium, with the exception of dipyrone for the EFM19A and EFM9A strains. The isolates showed good antagonistic activity against gram-negative, as EFM9A, EFM55 and EFM67 strais with better activity. The highest fermentation was observed in 42 ºC, showed the pH variation of 4.15 to 5.15, after 48 hours of fermentation. All isolates showed pH reduction at 20 ºC. However, all isolates produced higher titratable acidity at a temperature of 42ºC. The isolates EFM55 and EFM9A has had probiotic actived, biochemical and susceptibility parameters desirables, aim it’s technological potential in the production of dairy products.

Genome-based studies indicate that the Enterococcus faecium Clade B strains belong to Enterococcus lactis species and lack of the hospital infection associated markers

“…Concerning the pili gene clusters PGC-3 and PGC-4, none of the strains showed complete identity profiles for the entire array of genes forming the PGCs. The lack of genetic markers for virulence, incomplete set of PGCs [1–4], together with the susceptible ampicillin genotype of E. lactis and clade B, support the safety of this taxonomic unit and the clear separation from virulent and AM resistant isolates (Clade A2 and A1).…”

“…It is found in a large number of foods, mainly fermented products of animal origin like cheeses and dry sausages [1], where they are part of the natural ripening processes or added as starter cultures. Some strains of this species have been recognized also as probiotics conferring benefits to their hosts [2, 3]. However, in the past three decades, E.…”

Enterococci from Raw-Milk Cheeses: Current Knowledge on Safety, Technological, and Probiotic Concerns

“…isolates from Kashar cheese lowered it to 4.08 for 24 h [106]. According to results reported by de Paula et al [107], better acidification values can be achieved by prolonging cultivation time. A few authors reported that E. faecalis strains reduce milk pH faster than E. faecium and E. durans strains [22,108].…”