Potential of high pressure homogenization in the control and enhancement of proteolytic and fermentative activities of some Lactobacillus species

• Published in: Food chemistry Vol. 102; no. 2; pp. 542 - 550
• Main Authors: Lanciotti, Rosalba, Patrignani, Francesca, Iucci, Luciana, Saracino, Pasquale, Guerzoni, M. Elisabetta
• Format: Journal Article Conference Proceeding
• Language: English
• Published: Oxford Elsevier Ltd 2007; Elsevier
• Subjects: acidification; Biological and medical sciences; casein; electrophoresis; enzyme activity; Fermentative kinetics; Food industries; Food microbiology; Fundamental and applied biological sciences. Psychology; High pressure homogenization; high pressure treatment; homogenization; homogenized milk; lactic fermentation; Lactobacillus; Lactobacillus species; milk; product improvement; proteinases; proteolysis; Proteolytic activity; reaction kinetics; starter cultures; strain differences; viability; volatile compounds; Lactobacillus species; Proteolytic activity; High pressure homogenization; Fermentative kinetics; Lactic acid bacteria; Physical dressing; Homogenization; Fermentation; High pressure; Proteolysis; Bacteria; Lactobacillaceae; Kinetics; Species; Lactobacillus
• ISSN: 0308-8146; 1873-7072
• DOI: 10.1016/j.foodchem.2006.06.043

Different species of Lactobacillus involved in dairy product fermentation and ripening were considered in order to study the effect of high pressure homogenization (HPH) on: (i) fermentation kinetics of HPH treated cells inoculated in milk; (ii) metabolic profiles; (iii) release of intracellular proteolytic enzymes; and (iv) enhance of the activity of extracellular or cellular wall located proteolytic enzymes. The HPH treatments applied were 50, 100, 150 MPa, 2 cycles at 50 and at 100 MPa. The viability loss did not exceed 1.3 log cfu/ml after the higher treatments applied. The electrophoretic profiles of α- or β-casein incubated with the different cell free filtrates shown that HPH positively affected the proteolytic activity of some strains. Moreover, HPH affected the acidification rates of the milk inoculated with the processed cells and the primary metabolism of some strains. Regarding volatile compounds, ethanol, acetoin and 2-methyl butyric acid were subjected to the major changes when the inoculum had been processed.