Lipase production by yeasts from extra virgin olive oil

Microbial Biotechnology in Olive Oil Industry

“…The microbiological analyses highlighted the presence of yeasts, but not of bacteria and moulds (Ciafardini and Zullo 2002). Several isolated genus of yeasts were identified as Saccharomyces, Candida and Williopsis (Ciafardini et al 2006). …”

“…Furthermore, the free fatty acids of olive oil proved to be good inducers of lipase activity in both yeasts. The microbiological analysis carried out on commercial extra virgin olive oil demonstrated that the presence of lipase-producing yeast varied from zero to 56% of the total yeasts detected (Ciafardini et al 2006). Some dimorphic species can also be found among the unwanted yeasts present in the olive oil, considered to be opportunistic pathogens to man as they have often been isolated from immunocompromised hospital patients.…”

Microbiological characterization of Picholine variety olives and analysis of olive oil produced in traditional oil mills in Morocco

“…That increase might be due to the presence of mesophilic and psychrotrophic bacteria, moulds and yeasts that produced lipases and caused triglyceride hydrolysis (Ciafardini et al, 2006;Ertuğrul et al, 2007;Zullo & Ciafardini, 2008).…”

“…The milling of olives can lead to the development of mesophilic and psychrotrophic bacteria, moulds and yeasts (Ciafardini, Zullo, & Iride, 2006), and consequently the generation of lipases (Ertuğrul, Dönmez, & Takaç, 2007;Zullo & Ciafardini, 2008), responsible for triglyceride hydrolysis and the increase of free fatty acids, which become very sensitive to autoxidation in the bulk oil (Kinsella, Shimp, & Mai, 1978). In addition, oxidized triglycerides had high pro-oxidant activity (Kiritsakis, Nanos, Polymenopulos, Thomai, & Sfakiotakis, 1998), reduced the induction time of oxidation and increased the concentration of oxidized triglycerides.…”

Modern Methodologies to Assess the Olive Oil Quality

“…Microbiological studies have recently demonstrated the occurrence in the suspended fraction of freshly produced olive oil of a rich microflora mainly composed of yeasts 37 which, probably, induces the presence of lipase. 38 This fact can explain the many changes observed in the triglycerides profiles during aging as a consequence of the lipase action 39 and to the presence of several mono and di carboxylic acids in olive oil derived from many types of biotransformation.…”