Τεχνολογικός χαρακτηρισμός και αξιολόγηση ασφαλείας οξυγαλακτικών βακτηρίων από γάλα όνου

Abstract

Over the past decades there has been an increase in the interest in the use of enterococci with their desirable technological properties as to the starter cultures, co-cultures or probiotic due to their ability to survive in the gastrointestinal human system. However the ideal choice of starter cultures is considered an interdisciplinary approach in order to select the appropriate microorganisms for industrial applications. Furthermore, the exemption of these microorganisms from infectious agents and particularly resistance to antibiotics are very important criteria. Based on the importance of microorganisms, with giving more attention to the enterococci, this assay is focused on the technological characteristics and the safety assessment of the lactic acid bacteria isolated from donkey milk in order to determine the possibility of their use as starter cultures in fermented dairy products. In a previous study 257 Gram-positive, catalase negative bacteria were isolated, from eleven samples of Cyprus donkey raw milk by using selective microbiological media. All isolates were previously identified by phenotypic and molecular techniques in a previous study. Therefore, in this study the isolates were tested for the technological and probiotic properties. Additionally, in order to assess the suitability of the microorganisms as starter cultures, their sensitivity to antibiotics was studied as well as the presence or absence of infectious agents (hemolytic activity as well as the presence of lipase and gelatinase). The general profile of safe isolates showed that enterococci in raw donkey milk pose no risk to human health, as many of the microorganisms seem to survive in the human gastrointestinal system, while having adequate technological and probiotic properties. These microorganisms could potentially be further exploited by the food industry particularly in the areas of food microbiology (Biosafety / bio-maintenance) or the technology of fermented milk products.