Variablit Some Microbiol Ogical and Chemical Properties of Tej Between and Within Some Vending Houses in Addis Ababa
No Thumbnail Available
Date
2000-07
Authors
Journal Title
Journal ISSN
Volume Title
Publisher
Addis Ababa University
Abstract
'tej' being honey wine, is one of the primitive types of wines that are not crystal clear,
but cloudy, effervescent, containing residues of substrates, the fermenting yeasts and
other microorganisms. Honey wines are prepared and consumed in many parts of the
world. 'tej' is consumed widely in many parts of Ethiopia and is prepared from honey, or
honey and sugar, water and Gesho (Rhamnus prenoides). Roots, stems or leaves of plants
are added assuming atlincrease in the alcohol content and its potency. Like any other
spontaneous fermentation, 'tej', in its fermentation, relies on the microorganisms that
inhabit the must from different sources. The substrates, utensils, equipment, and the
envirorunent are responsible for the randomization of the micro flora. In such spontaneous
fermentation and un-optimal physical and chemical conditions, variability in the product
quality and stability becomes inevitable. So, investigating the variability and its extent in
some microbiological and chemical properties of 'tej' at the time it was ready for
consumption, was the objective of this study.
At consumption stage, 'tej' was highly loaded with yeasts and Lactic acid bacteria.
Members of different genera of yeasts, members of the bacterial genera of Lactobacillus,
Pediococcus, Streptococcus, Leuconostoc, were isolated and identified. Of the yeast
isolates, species of Saccharomyces were dominant, followed by Kluyveromyces,
Debal'O/11yces, Hansel1ula, Endomycopsis and Pichia specIes. Generally, the
homofermentative (52.09%) were higher in counts than the heterofennentative( 47.91 %)
lactic acid bacterial population.. All the isolates from the aerobic mesophilic bacterial
plates were identified as members of Baci I/lls.
All the studied microbiological and chemical properties of 'te}' had significant variability
among samples within each vending house. Also, except yeast and lactic acid bacterial
populations and fusel oil contents, all the other microbiological and chemical properties
of 'te} , studied had statistically significant variability (AN OVA, p < 0.004 for all)
between the mean values of all the vending houses. Generally, all samples also showed
variability in their total alcohol, total lipid, protein, and reducing sugar. Variability in
fusel oil, titratable acidity and total carbohydrate was also noted. So, 'te}' at the time it
was ready for consumption had statistically significant variability both within and
between vending houses in the microbiological and chemical properties.
Description
Keywords
Biology