Evaluation of selected functional traits in lactic acid bacteria isolated from Algerian Makatia goat milk for food applications

While studies on the health aspects of lactic acid bacteria (LAB) may receive more attention from the scientific community, the focus on the technological aspects of these bacteria has also become equally important, as these bacteria possess physiological properties that qualify them for use in various food productions. This study examined some of these traits for 10 LAB isolates from Makatia goat milk in the Wilaya of Mascara in western Algeria. Tests were conducted to evaluate acidifying activity, enzymatic activity, growth capability at different pH levels, in high salt environments, different temperatures, exopolysaccharide (EPS) production, high-temperature tolerance, antagonistic activity, and antibiotic sensitivity. All isolates lacked amylolytic activity, while proteolytic activity varied between 14.33 and 32.67 mm of lysis zones, and lipolytic activity varied between 8.43 and 12.53 mm. Thermotolerance at 63 °C for 30 minutes was revealed for all 10 isolates, along with variable growth capacities under different conditions (high, low pH, salted environment, and different temperatures). Significant antagonistic activity ranged between 11.5 and 40.66 mm of inhibition zones against the tested indicator strains. All 10 LAB isolates from goat milk exhibited remarkable technological properties that may or may not be helpful in food technology. For example, they are desirable in the fermentation industry and undesirable in some pasteurisation-sensitive products or some meat food industries.