Kelvaragu Koozh: a traditional fermented finger millet beverage of south India with ethnographic and nutritional significance

Abstract Finger millet ( Eleusine coracana ), also referred to as ragi in India, is a nutritious cereal, well known for its excellent mineral profile and high calcium content. Often referred to as the “Queen of Millets,” ragi is valued for its easy digestibility and nutritional value. Kelvaragu koozh is a traditional fermented finger millet-based beverage that has long been consumed as a staple breakfast food among the Tamil population of Tamil Nadu, South India. In earlier times, it was a vital component of daily diets of farmers, manual labourers, and heavy workers, providing sustained energy, hydration, and overall nourishment at low cost. Beyond its nutritional value, kelvaragu koozh holds deep cultural and religious significance in South Indian traditions. The present study aims to document the traditional preparation methods of kelvaragu koozh through an ethnographic study comprising, open-ended interviews and participant observation with 60 elderly individuals (farmers and local elders, aged 50–80 years) from the Tiruchirappalli district of Tamil Nadu. The study also documents indigenous knowledge on ingredient selection, fermentation techniques, and dietary practices, providing an understanding of kelvaragu koozh as a healthy, cost-effective, and complete breakfast across socioeconomic groups. Additionally, the study reviews the nutritional and health-relevant attributes of finger millet as reported in existing literature, with a focus on its role as a functional fermented food. The work underscores the importance of preserving and documenting traditional food knowledge and ethnic fermented foods in modern wellness diets. The work also emphasizes the need to keep traditional food knowledge viable.