Microbiological characterization of protected designation of origin Azeitão cheese

Abstract

Azeitão is an appreciated Portuguese protected designation of origin (PDO) cheese produced following artisanal procedures using ovine raw milk, Cynara cardunculus L. flower and salt. Although its origins trace back to the early 1800s, limited research regarding the characterization of its microbiota is available. So, this work aimed to perform a microbiological characterization of Azeitão PDO cheeses and raw materials obtained from a certified producer throughout the 2020/2021 production campaign, focusing on Lactic Acid Bacteria (LAB) composition. The results showed that LAB content in cheeses exceeded 8.8 log CFU/g. Overall, lactococci and lactobacilli predominated over enterococci and Leuconostoc spp. strains. A Multiple Correspondence Analysis also identified L. curvatus, L. mesenteroides, L. plantarum, L. paracasei and L. lactis as crucial constituents of these cheeses´ microbiota. Milk matrices were associated with enterococci and L. rhamnosus strains, while curd shared a higher similarity with cardoon samples due to their content on Weissella spp. and enterococci strains. In the end, this characterization contributes to a deeper understanding of the scientific community, producers and the public in general, of the microbiota, especially LAB, that is associated with a PDO cheese, whose knowledge is so far scarce.