World Academic Research Journals
World Academic Journal of Food Science, Human Nutrition and DieteticsISSN - 2671-4310
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World Academic Journal of Food Science, Human Nutrition and Dietetics

Investigation of Changes in pH, titratable acidity, Enterobacteriaceae, aerobic mesophiles, lactic acid bacteria (LAB) and yeast counts during borde fermentation


World Academic Journal of Food Science, Human Nutrition and Dietetics ISSN 2671-4310 Vol. 2(3),pp 231-239 June, 2017. © World Academic Research Journals

Full Length Research Paper

 

Investigation of Changes in pH, titratable acidity, Enterobacteriaceae, aerobic mesophiles, lactic acid bacteria (LAB) and yeast counts during borde fermentation

 

Berhanu Wolde

Department of Food Science and Post-harvest Technology, Awassa College of Agriculture, Debub University, Ethiopia.

E-mail: berhanuwolde95@yahoo.co.uk.

 

Accepted 13 March, 2017

 Abstract

Changes in pH, titratable acidity, Enterobacteriaceae, aerobic mesophiles, lactic acid bacteria (LAB) and yeast counts were investigated during borde fermentation. A rapid decrease in pH was associated with accelerated growth rate of LAB and inhibition of Enterobacteriaceae. Wide diversities of LAB strains were present at early stage of borde fermentation. The number of species reduced as the fermentation progressed. Representatives of LAB involved in borde fermentation were isolated at 6 h intervals, characterized and identified using physiological and biochemical methods including API 50CH kit. The LAB strains were grouped into 3 major and 2 minor clusters. Most of the LAB strains were heterofermentative lactobacillus (79.4%), while pediococcus species dominating the cocci (20.6%). Weissella confusa, Lactobacillus brevis, Lactobacillus viridescens, Pediococcus pentosaceus and P. pentosaceus subsp. intermedius were identified throughout borde fermentation as dominant LAB. The frequency of dominating strains were: W. confusa (30.9%), Lb. viridescens (26.5%), Lb. brevis (10.3%) and P. pentosaceus (7.4%) and P. pentosaceus subsp. intermedius (8.8%), while sporadically isolated species of Lactobacillus curvatus, P. acidilactici, Lactobacillus collinoides, Lactobacillus sanfrancisco, Lactobacillus pontis and Lactobacillus delbrueckii subsp. delbrueckii were 16.3%. The dominating LAB strains can be potential starter cultures for borde fermentation.

 

Key words: Beverage, cereal fermentation, Ethiopian borde, identification, lactic acid bacteria.