Traditional Ethiopian fermented condiments: a systematic review of microbial dynamics, nutritional transformations,...

Traditional Ethiopian fermented condiments, including Siljo, Datta, Awaze, Helbat, and Azo, are culturally significant and nutritionally valuable. Despite their importance, evidence on their microbial ecology, nutritional transformations, safety, and functional potential remains fragmented and insufficiently characterized. This systematic review, conducted in accordance with PRISMA 2020 guidelines, consolidates current knowledge on the microbial dynamics, nutritional changes, probiotic traits, and food safety of these traditional Ethiopian fermented condiments. A comprehensive literature search was carried out up to December 2025 across PubMed, Scopus, Cochrane Library, Epistemonikos, and Google Scholar. Studies consistently reported that lactic acid bacteria-particularly Lactiplantibacillus plantarum, Pediococcus pentosaceus, and Weissella spp.-dominate spontaneous fermentations, driving acidification to pH values typically between 3.6 and 4.5 and contributing to pathogen suppression. Fermentation also induced product-specific nutritional transformations, including changes in protein content and digestibility, mineral dynamics, and the formation of bioactive compounds. However, outcomes varied considerably depending on substrate composition, microbial consortia, and processing conditions. Data on antinutritional factor reduction (phytates, tannins, and trypsin inhibitors) were absent across all included studies, representing a critical knowledge gap. Despite these promising attributes, research on these condiments is largely limited by reliance on culture-dependent methods, heterogeneous fermentation practices, and inconsistent analytical approaches. The evidence base for some condiments, particularly Azo and Datta, is further constrained by reliance on grey literature and secondary data sources. To fully harness their microbial, nutritional, and commercial potential, future studies should employ integrated research methodologies based on standardized fermentation protocols, metagenomics, metabolomics, and comprehensive nutritional assessments.

The online version contains supplementary material available at 10.1007/s13197-026-06764-y.