Functional and safety aspects of enterococci in dairy foods

Abstract

The genus Enterococcus like other LAB has also been featured in dairy industry for decades due to its specifi c biochemical traits such as lipolysis, proteolysis, and citrate breakdown, hence contributing typical taste and fl avor to the dairy foods. Furthermore, the production of bacteriocins by enterococci (enterocins) is well documented. These technological applications have led to propose enterococci as adjunct starters or protective cultures in fermented foods. Moreover, enterococci are nowadays promoted as probiotics, which are claimed for the maintenance of normal intestinal microfl ora, stimulation of the immune system and improvement of nutritional value of foods. At the same time, enterococci present an emerging pool of opportunistic pathogens for humans as they cause disease, possess agents for antibiotic resistance, and are frequently armed with potential virulence factors. Because of this 'dualistic' nature, the use of enterococci remains a debatable issue. However, based on a long history of safe association of particular enterococci with some traditional food fermentations, the use of such strains appears to bear no particular risk for human health. Abundance of knowledge as well as progress in molecular techniques has, however, enabled exact characterization and safety assessment of strains. Therefore, a balanced evaluation of both, benefi cial and undesirable nature of enterococci is required. A clear understanding of their status may, therefore, allow their safe use as a starter, or a probiotic strain. The present review describes the broader insight of the benefi ts and risks of enterococci in dairy foods and their safety assessment.

Starter cultures used in probiotic dairy product preparation and popular probiotic dairy drinks

“…However recent studies have shown that E. faecalis and some lactic acid bacteria species can cause clinical infections, especially infective endocarditis. E. faecalis can be found not only in human and animal faeces but also on plants and this largely reduces it's usage as a sanitation indicator (Foulquié Moreno et al, 2006;Giraffa, 2003;Kaleli & DurluOzkaya, 2000;Bhardwaj et al, 2008).…”

Effect of a dietary probiotic blend on performance, blood characteristics, meat quality and faecal microbial shedding in growing-finishing pigs

“…Probiotic bacteria Lactobacillus and Bacillus subtilis have been successfully applied to livestock species (Abdelqader et al, 2013). These two strains benefit animals by suppressing pathogens directly or indirectly (Bhardwaj et al, 2008;Seidavi et al, 2017). However, single species often expose limited functionality, leading to instability in aspects of the using effect (Zhang et al, 2017).…”

Probiotic mixture ameliorates heat stress of laying hens by enhancing intestinal barrier function and improving gut microbiota

“…Recently, the probiotic bacteria Lactobacillus (Sohail et al 2010) and Bacillus subtilis (Abdelqader et al 2013) have been applied to birds. The two strains benefit animals by suppressing pathogens directly or indirectly and reduce the occurrence of diseases (Tsaruk'ianova & Smirnova 2005;Bhardwaj et al 2008). But single species often exposed limited functionality, which led to instability in the aspect of using effect.…”