Use of an autochthonous defined whey starter culture for the industrial production of Gran Ovino, a Sicilian ewe’s milk cheese

Abstract

This study reports the industrial scale-up of Gran Ovino (GO), an extra-hard Sicilian ewe’s milk cheese originally developed at an artisanal level, with the aim of preserving its territorial identity while ensuring food safety and enhancing quality. Cheese production was carried out under industrial conditions using pasteurized milk and two different starter systems: a defined whey starter culture (DWSC) composed of selected Streptococcus thermophilus strains (EXP-GO) and a commercial starter culture (CTR-GO) as control. Microbiological analyses confirmed the hygienic and sanitary quality of both trials, with high levels of lactic acid bacteria (LAB) and absence of spoilage or pathogenic microorganisms. Metataxonomic profiling revealed the dominance of Streptococcus and Lactobacillus genera in ripened cheeses. After 12 months of ripening, EXP-GO cheese exhibited a more favourable fatty acid profile than CTR-GO, characterized by higher oleic acid levels and lower concentrations of trans fatty acid isomers. It also showed greater hardness and a more complex volatile organic compound (VOC) composition dominated by ketones, esters, and volatile acids. Sensory evaluation highlighted some differences in the appreciation of individual attributes between EXP‑GO and CTR‑GO. Overall, the use of DWSC enables the industrial production of Gran Ovino cheese with distinct compositional and sensory profiles, while maintaining its link to local tradition and biodiversity. These findings demonstrate that the use of DWSC enables the industrial production of Gran Ovino cheese with enhanced nutritional and sensory characteristics, while maintaining its link to local tradition and biodiversity.