# Development of \"Quadrello di Ovino\", a Novel Fresh Ewe's Cheese
## 4 Discussion  
Sicily is a southern Italian region where cheese making is a very ancient daily activity [32]. Up to date, five out of 33 traditional cheeses produced in Sicily enjoy a PDO status: Vastedda della valle del Belice, Pecorino Siciliano, Piacentinu Ennese, Provola dei Nebrodi, and Ragusano. Among these, only ewe's milk Vastedda della valle del Belice cheese can be considered a fresh product [33]. Except this particularly rare example, in Italy ewe's milk is generally transformed to produce hard or semi-hard cheeses, especially in the south part of the country [17]. The main hypothesis of this work was that a new typology of cheese could be produced from ewe's milk and that this fresh cheese could be well appreciated by consumers. With this in mind, Qdo cheese was processed with commercial culture preparations of _Streptococcus thermophilus_, typical thermophilic dairy LAB [34], used as starters for Crescenza cheese production [31; 35; 36]. Among fresh cheese, Crescenza is an Italian product particularly appreciated by consumers [37]. It is a soft rindless cheese with a very short ripening time, processed from pasteurized cow's milk in the northern Italy, mainly in Lombardia region [38]. Regarding the inoculums for curd acidification, two different commercial preparations were used in order to evaluate the influence of different strains on the final characteristics of Qdo cheese. The metabolic activities of _Streptococcus_ strains are particularly flexible and diverse [39] and metabolomics are being widely applied for food quality analyses [40]. Thus, the use of different starter strains might provide unique metabolomics for the final products. For this reason, in this work two commercial starter preparations were used. The pasteurised bulk mills were microbiologically investigated, and the densities of LAB were almost at the same level of TMM. These results might be ascribable to the ability  
Figure 3: Spider diagrams of descriptive sensory analysis of cheeses. Abbreviations: CCCch, commercial crescenza cheese; Qdo-P1, Quadrello di ovino cheese produced with starter culture SF1 (starter formulation CR/A); Qdo-P2, Quadrello di ovino cheese produced with starter culture SF2 (starter formulation LYOBAC-D CRM). \(p\) value: \({}^{*}\)\(p<0.05\); \({}^{**}\)\(p<0.01\); \({}^{***}\)\(p<0.001\); n.s., not significant. of the indigenous milk bacteria to survive during the pasteurization process [41; 42], but also to a post-pasteurization contamination [43; 44]. Furthermore, this phenomenon seems to be common in pasteurized ewe's milk [8; 16; 45]. All undesired bacteria (_Pseudomonas_, members of Enterobacteriaceaeae family, _L. monocytogenes_, _Salmonella_ spp., _E. coli_ and CPS) were undetectable. [PERSON] et al. [45] reported similar findings for pasteurized ewes' milk used for another fresh ewe's milk cheese production, Pecorino \"Primosale\". After inoculation, starter cultures were monitored during cheese making. They increased until \(10^{8}\) CFU/g in curds as a consequence of whey draining [46]. Both QdO cheese productions showed LAB levels of about 9 Log CFU/g following the general trend commonly observed for ovine pressed cheeses [8; 47]. The cheeses were analyzed for several quality parameters, first of all for their physical characteristics (color and hardness). Color represents an important quality index of soft cheeses, including Crescenza type, that strongly affects the acceptability by consumers [48]. The three color parameters lightness, redness and yellowness of QdO cheese were, on average 87.31, \(-\)4.29, and 16.03, respectively. These values are comparable to those of the only fresh ewe's milk cheese (Vastedda della valle del Belice) produced in Sicily [49]. Regarding redness, the results of QdO cheeses are almost identical to that of Roncal cheese [50], while yellowness is quite lower than those characterizing several ripened cow's milk chees. The initial b* values of soft cow's milk Stracchino (synonymous of Crescenza) chees are in the range 11.5-12.0 [51]. [PERSON] et al.