Molecular identification of yeast and lactic acid bacteria species from Ethiopian Awaze paste (a traditional fermented spicy red pepper paste) of Ethiopia

Abstract

Fermentation, driven by microorganisms such as yeast and lactic acid bacteria, enhances food quality by improving shelf life, flavor, texture, and safety. Ethiopia is home to a diverse range of traditional fermented foods with significant cultural and nutritional value. This study aimed to identify yeast and LAB species involved in the fermentation of Awaze paste using molecular techniques. Awaze samples were prepared based on a traditional recipe using red pepper, garlic, red onion, and a blend of ten spices, then fermented under controlled conditions for 300 days. At the end of fermentation, selective media were used to isolate yeasts and LAB, followed by genomic DNA extraction. Molecular identification involved PCR amplification of the internal transcribed spacer (ITS) region for yeasts and the 16 S rRNA gene for LAB, followed by sequencing and phylogenetic analysis. Two yeast and four LAB isolates were identified. The yeast isolates belonged to the genus Candida , showing 97% sequence similarity to Candida sp. strain WSYC780. The LAB isolates were identified as Weissella confusa and Weissella cibaria , with 92–95% similarity to known strains. These findings indicate that Awaze paste harbors a unique microbial community distinct from other Ethiopian fermented products, likely due to differences in ingredients and fermentation conditions. The presence of Candida spp., W. confusa , and W. cibaria highlights their functional role in Awaze fermentation and potential use in starter culture development. This study provides the first molecular characterization of Awaze paste microbiota and lays the groundwork for improving its quality, safety, and commercial production.