Microbiological diversity and biotechnological characteristics of the dominant indigenous lactic microflora in Algerian traditional butter (Dhan)
Keywords:Milk, Fermentation, Lactic acid bacteria, Traditional butter, Technological characteristics
Traditional butter is widely used in pastoral populations in Algeria, thanks to its nutritional value. Several studies have investigated traditional butter produced in Algeria, our study is a contribution to its improvement and valorisation through the phenotypic identification and characterization of lactic acid bacteria responsible for the fermentation of this product. The samples were collected in the regions of Relizane, Oran, Sidi Bel-Abbes and Tindouf. Physicochemical tests make it possible to specify the quality of traditional butter; the pH is 4.5 ± 0.02 to 5.31 ± 0.2, the fat content is 73 ± 0.2 to 83 ± 0.1%, the acid index is 28.05 ± 0.2 to 44.88 ± 0.2 mg KOH.g-1 and the saponification index is 131.85 ± 0.2 to 359.10 ± 0.2 mg KOHg.-1. The microbiological analysis results show that the lactic microflora isolated from butter consists mainly of different genera; Lactobacillus 49%, Lactococcus 20%, Leuconostoc 15%, Enterococcus 11% and Pediococcus 5%. Species identification is based on classical phenotypic characterization; Lb. plantarum 7 isolates (26%), Lb. casei subsp. casei 6 isolates (22%), Lb. casei subsp. rhamnosus and Lb. delbrueckii subsp. bulgaricus 5 isolates (19%), Lb. delbrueckii subsp. delbrueckii 4 isolates (14%), Lc. lactis subsp. cremoris 6 isolates (55%), Lc. lactis subsp. lactis 5 isolates (45%), Ln. mesenteroides subsp. dextranicum 5 isolates (62%), Ln. mesenteroides subsp. mesenteroides 3 isolates (38%), E. faecalis 4 isolates (67%), E. faecium 2 isolates (33%), P. acidilactici3 isolates (100%). They have considerable biotechnological characteristics which allow the constitution of specific starters in the manufacture of Algerian traditional butter.