Unveiling the sociocultural, microbiological, and functional properties of liquid brem, a traditional balinese fermented rice wine: a systematic review

Abstract Balinese brem is a traditional Indonesian fermented rice wine embedded in cultural, ritual, and spiritual practices, serving important symbolic and social functions. Beyond its cultural significance, brem has attracted scientific attention in fermentation science, microbial ecology, biochemical composition, and potential functional properties. However, existing studies often examine these aspects separately, resulting in a fragmented understanding of brem as both a cultural heritage product and a fermentation-derived beverage. This systematic review adopts a multidisciplinary framework integrating sociocultural context with microbial, biochemical, and technological perspectives to synthesize current knowledge on brem . Brem fermentation involves a consortium of microorganisms, including amylolytic molds (e.g., Rhizopus, Mucor, and Amylomyces ), yeasts predominantly Saccharomyces fibuligera and Pichia anomala , and lactic acid bacteria (LAB) such as Pediococcus pentosaceus , Enterococcus faecium, Lactobacillus curvatus , and Weissella . Amylolytic fungi hydrolyze starch into fermentable sugars, yeasts convert these sugars into ethanol, and LAB contribute to acidification and flavor development. Microbial metabolism generates metabolites, including organic acids, amino acids, alcohols, and volatile compounds that shape sensory attributes and quality of brem . This review highlights that microbial community composition, fermentation conditions, and processing practices influence product quality, safety, and sensory characteristics, supporting controlled fermentation for optimization. Although fermented rice wines may offer functional benefits, specific bioactive compounds in brem remain insufficiently characterized. Advances in fermentation management and processing technologies are discussed in relation to product standardization, safety assurance, and commercialization. Collectively, this review provides a scientific foundation for preserving Balinese cultural heritage and promoting the sustainable development of fermented beverages.