Development of mixed starter culture for the fermentation of Ethiopian honey wine, Tej

Abstract

Ethiopian honey wine is one of the country's most popular spontaneously fermented traditional alcoholic beverages. However, the final product of this natural fermentation system is frequently of poor and inconsistent quality. Furthermore, it makes the process difficult to predict, control, and correct. Thus, the main aim of this study was to develop a direct fermentation system for Ethiopian honey wine, Tej. After isolating fermentative microbial strains from Tej samples, they were subjected to intensive screening to fit to its purpose. Later, phenotypic and genotypic characterization, and inoculation of isolates to honey-must were performed sequentially. Finally, microbial interaction and physicochemical analysis, including volatile compounds profiling, were done for the inoculated samples. The identified isolates were strains of Saccharomycetaceae and Lactobacillaceae families. These strains showed a good ability to tolerate osmotic stress and a lower pH environment. Tej sample produced by mixed culture inoculation of Saccharomyces and Lactobacillus species showed similar physicochemical, volatile compounds, and sensory attributes values with that of the control sample. Thus, a mixture of Saccharomyces and Lactobacillus strains could be used as a starter culture to produce Ethiopian honey, Tej, without scarifying of its major quality attributes.

Microbial, physicochemical and proximate analysis of Tej collected from Amhara regional state of Ethiopia

“…In many fermentation processes, some group of microorganisms, particularly LAB and yeast species have synergistic activity towards the co-fermentation of the common substrate as reported by many researchers [ [29] , [30] , [31] ]. Recently, metagenomics study of spontaneously fermented Tej revealed the presence of several species of Saccharomyces and Lactobacillus [ 19 , 32 ]. The positive interactions of LAB and yeast species in the fermentation process results in the development of organoleptic, nutritional and safety of the final products of alcoholic beverages, including Tej [ 28 ].…”