Traditional cheeses made without starter cultures can be characterised bythe attribute of instability. The addition of autochthonous starter cultures can ensurestability without compromising the characteristics of the final product. This studyaimed to characterise the autochthonous lactic acid bacteria (LAB) population in“Vastedda della valle del Belìce” cheeses, which have a protected designation oforigin (PDO) status, in order to develop an ad hoc starter culture to be used in itsfuture production. Winter and spring productions were analysed to ensure isolation ofspecific LAB that had adapted to perform fermentation at low temperatures. Platecounts revealed total microbial numbers nearing 109 CFU.g−1. All of the cheesesamples were dominated by coccus-shaped LAB. When enterobacteria were present,their concentrations were at similar levels (3.3–5.6 Log CFU.g−1) in both seasons. Allof the colonies that differed in morphological appearance were isolated anddifferentiated on the basis of phenotypic characteristics and genetic polymorphisms,as analysed by random amplification of polymorphic DNA-polymerase chain reaction.A total of 74 strains were identified and further genotyped by sequencing the16S rRNA gene, resulting in the identification of 16 LAB species belonging to five genera(Enterococcus, Lactobacillus, Lactococcus, Leuconostoc and Streptococcus). The speciesmost frequently present were Streptococcus gallolyticus subsp. macedonicus, Streptococcusthermophilus, Lactococcus lactis and Leuconostoc mesenteroides. The 74 strains were alsoinvestigated in vitro for general dairy parameters such as acidification capacity,diacetyl generation and antibacterial activity. Several strains of the most frequentlyrepresented species displayed traits relevant to the production of PDO “Vasteddadella valle del Belìce”.
|Numero di pagine||24|
|Rivista||DAIRY SCIENCE & TECHNOLOGY|
|Stato di pubblicazione||Published - 2014|
All Science Journal Classification (ASJC) codes
- Food Science