The Impact of Different Inoculation Schemes on the Microbiota, Physicochemical and Sensory Characteristics of Greek Kopanisti Cheese throughout Production and Ripening

Kopanisti is a Greek PDO cheese, which is traditionally produced by the addition of an amount of over-mature Kopanisti, called Mana Kopanisti, to initiate cheese ripening. The aim of this study was the production of four types of Kopanisti cheese (A–D) using pasteurized cow milk, and a combination of the following starters/adjuncts in order to test their ability to be used in Kopanisti cheese production: A: <i>Lactococcus lactis</i> subsp. <i>lactis</i> and <i>Lacticaseibacillus paracasei</i>, B: <i>L. lactis</i> and <i>Lc. paracasei</i>/Mana Kopanisti, C: <i>L. lactis</i> and <i>Lc. paracasei</i>/<i>Ligilactobacillus acidipiscis</i> and <i>Loigolactobacillus rennini</i>, D: <i>Lig. acidipiscis</i> and <i>Loig. rennini</i>. Throughout production and ripening, classical microbiological, metataxonomics and physicochemical analyses were employed, while the final products (Day 35) were subjected to sensory analysis as well. Most interestingly, beta-diversity analysis of the metataxonomics data revealed the clusters constructed among the Kopanisti types based on the different inoculation schemes. On day 35, Kopanisti A–C types clustered together due to their similar 16S microbiota, while Kopanisti D was highly differentiated. On the contrary, ITS data clustered Kopanisti B and C together, while Kopanisti A and D were grouped seperately. Finally, based on the sensory evaluation, Kopanisti C appeared to have the most suitable bacteria cocktail for the Kopanisti cheese production. Therefore, not only were the conventional starters used, but also the <i>Lig. acidipiscis</i> and <i>Loig. rennini</i> strains could be used in a standardized Kopanisti cheese production that could lead to final products of high quality and safety.