Production of Crescenza cheese by incorporation of bifidobacteria

Bifidobacterium bifidum, Bifidobacterium infantis, and Bifidobacterium longum were incorporated into Crescenza cheese, individually or as multispecies mixtures and as free cells or as cells immobilized in calcium alginate gel. The viability of the bifidobacteria differed in 14-d-old cheeses: when added individually, the cell counts of B. bifidum, B. longum, and B. infantis were log(10) 8.05, 7.12, and 5.23 cfu/g, respectively. The multispecies mixtures only reached about log(10) 5.0 cfu/g of cheese. The presence of bifidobacteria did not influence the aerobic microflora, the growth of Streptococcus thermophilus used as starter, or the gross composition of the cheese. No differences were found in the primary proteolysis with respect to the conventional production of Crescenza cheese, but higher levels of pH 4.6-soluble N and more pronounced activities of aminopeptidase, iminopeptidase, dipeptidase, and tripeptidase were detected in all of the cheeses with added bifidobacteria. Crescenza cheeses with added bifidobacteria contained only traces of lactose and had slightly higher concentrations of lactic and acetic acids than did the conventional cheese. The presence of bifidobacteria was also related to high alpha- and beta-galactosidase activities in the cheese. Sensory evaluation of the cheeses with incorporated bifidobacteria was very similar to that of Crescenza cheese produced by the conventional method.