Synergistic and antagonistic properties of selected cultures of lactic acid and propionic acid bacteria. Part II. Proteolytic activity

The objective of this work was to study the dynamics of proteolytic activity for selected cultures of propionic acid and lactic acid bacteria used in the rennet cheese production. The studies were carried out in two model systems, with CH-N-19, Nizostar and their associated cultures in two media differing in the nitrogen compound structure. The addition of coagulating enzyme to the medium accelerated the proteolytic processes occurring upon the contribution of the examined cultures but did not influence the changes in the aminopeptidase specificity towards the substrates used (Leu-pNA for LAB and Pro-pNA for PAB).

Substrate specyfity of peptidases synthesised by Enterococcus facieum

The strain Enterococcus faecium successfully used in youghurt production was the subject of studies. It results from the comparison of the activities of peptidases synthesised by E. faecium that aminopeptidases dominated Their average activity was about 2.5-fold higher than the average activity of dipeptidases. The presence of carboxy- and tripeptidases is also important from the technological point of view.

Synergistic and antagonistic properties of selected cultures of lactic acid and propionic acid bacteria. Part I. Fermentation activity

The objective of this work was to study the dynamics of fermentation activity of selected cultures of lactic acid and propionic acid bacteria used in the cheese production. At the same time, it was decided to follow their interactions. The studies were conducted in two model systems with CH-N-19, Nizostar, and their associated cultures in two media. On a basis of the evaluation of physiological and fermentation activities, the antagonistic properties between the examined culture systems were not found and the differences observed only resulted from specific traits of the examined microorganisms.