Effect of adjuncts on microbiological and chemical properties of Scamorza cheese

Scamorza is a semi-hard, pasta filata cheese resembling low-moisture Mozzarella cheese, with a short ripening time (<30 d). Scamorza has a bland flavor and, to provide diversification from similar cheeses, it was manufactured using 2 types of milk in the current study: 100% Italian Friesian milk (F) or 90% F and 10% Jersey cow milk (mixed, M), and 2 types of starter: Streptococcus thermophilus or S. thermophilus with peptidolytic Lactococcus lactis, Lactobacillus helveticus, and Lactobacillus paracasei strains as adjuncts). The cheeses were ripened for 30 d. The adjunct did not significantly affect acid production or growth of the primary starter; 2 of the species used in the adjunct (Lb. paracasei and Lb. helveticus) rapidly colonized the cheese and persisted until the end of ripening, whereas the counts of nonstarter lactic acid bacteria in the control cheese were low until the end of ripening. The use of adjuncts affected pH, microbial composition (as assessed by both culture-dependent and culture-independent methods), total free amino acid content, and volatile profile (measured using an electronic nose), whereas milk type had only a minor effect. Although differences in primary proteolysis were found, they were probably indirect and related to the effects on pH and moisture. We conclude that, even with a short ripening time (30 d), use of a peptidolytic adjunct may significantly affect important features of Scamorza and may be used to create a product that is measurably different from competing products.