Indigenous Fermented Foods of North Bengal, India: A Comprehensive Review of Microbiota, Nutritional Enrichment, And Health-Promoting Potential

The Eastern Himalayan region of North Bengal, India, a melting pot of diverse ethnicities and traditions, harbours a rich and underexplored repository of indigenous fermented foods and beverages. These products, spanning categories of dairy, cereals, vegetables, bamboo shoots, and meats, are not merely dietary staples but are deeply intertwined with the socio-cultural and medicinal fabric of the local communities. Driven by spontaneous or back-slop fermentation, these foods host a complex consortium of lactic acid bacteria (LAB), yeasts, and acetic acid bacteria, which are the key architects of their unique organoleptic properties, bio-preservation, and health-promoting attributes. This comprehensive review systematically catalogues the predominant fermented foods of North Bengal, including Chhurpi (dairy), Kinema (soybean), Gundruk and Soidon (vegetables/bamboo), Kodo ko Jaanr or Chhang (finger millet beer), and various fermented fish products. We delve into the microbial ecology that underpins these fermentations, highlighting the dominant role of genera such as Lactobacillus, Pediococcus, Leuconostoc, and Saccharomyces. The paper critically evaluates the biotransformation occurring during fermentation, which enhances the bioavailability of nutrients, reduces anti-nutritional factors, and generates bioactive compounds like peptides, exopolysaccharides, and vitamins. The health perspectives, including improved gastrointestinal health through probiotics, enhanced antioxidant capacity, antihypertensive potential, and implications for metabolic and immune health, are discussed in detail. Furthermore, the review identifies challenges such as the lack of standardized industrial production, the threat of cultural erosion, and the need for robust clinical validation of health claims. It concludes by emphasizing the immense potential of these traditional foods as a source of novel probiotics and functional ingredients for the global health food market, advocating for a synergistic approach that integrates traditional knowledge with modern food science for sustainable development.