pH development
Initially after preparation, salamis had a pH of 5.8. pH decreased
in all samples over the course of the first three days of fermentation
to 4.8 and increased again slightly to 4.9 toward the end of
the fermentation 22 days after production (Fig. 4). This decrease
in pH during fermentation is characteristic and can be explained
by the metabolic activity of the starter cultures producing lactic
acid. The observed increase in pH towards the latter part of the fermentation
may be attributed to proteolysis (Dierick et al., 1974;
García de Fernando and Fox, 1991). In long ripened raw sausages
a pH increase of 0.1 has been reported previously due to the formation
of peptides and free amino acids (Klettner, 1984; Incze,
2004). The uniform pH decrease in all samples indicates that potential
differences in structure of products due to use of different
knife geometries had no influence on the metabolic activity of
the starter cultures and thus on pH decrease. An increase in bulk
mass temperature to 0 or +2 C prior to processing had also no effect
on the metabolic activity of the starter cultures and thus on the
pH development.