Predominant Lactic Acid Bacteria Involved in the Spontaneous Fermentation Step of Tchapalo Process, A Traditional Sorghum Beer of Cote D’ivoire

摘要

Fermented microflora involved in the spontaneous fermentation step of tchapalo processing was investigated. A total of 180 samples of the non fermented product (mash) and the fermented product (sour wort) were analysed by standard methods and Api 50 CH identification system. Difference in pH between mash (5.65) and sour wort (3.71) was significant (p Lactobacillus (5.5x108 cfu mL-1), Enterococcus (9.8x107 cfu mL-1), Pediococcus (9.7x107 cfu mL-1) and Leuconostoc (5.8x107 cfu mL-1). During the spontaneous fermentation there was an increase of the load of Lactobacillus, which remained predominant in sour wort at the end of fermentation (89.6%). The load of other lactic acid bacteria and yeasts decreased and this evolution varied according to areas. Thus, this spontaneous fermentation was essentially governed by Lactobacillus strains. The physiological analysis of 114 Lactobacilli randomly selected revealed 25 different profiles indicating a diversity of Lactobacillus strains implicated in the spontaneous fermentation. Almost all profiles observed were specific to the studied area. Among the Lactobacillus isolates from physiological study, there were 82.5% heterofermentative strains including Lactobacillus fermentum, Lactobacillus cellobiosus, Lactobacillus brevis, Lactobacillus coprophilus and 17.5% homofermentative strains including Lactobacillus plantarum.