Physicochemical, sensory analysis and gastronomic significance of Sambal Tumpang as a traditional Javanese fermented condiment

Sambal Tumpang, locally known as tumpang koyor, is a traditional Javanese condiment made from over-fermented tempeh (tempe semangit), chillies, coconut milk, and spices. Despite its deep cultural roots and culinary significance in Central Java, especially in Salatiga, there has been limited scientific exploration of this ethnic food. This study presents the first empirical analysis of Sambal Tumpang, integrating historical, socio-cultural, nutritional, sensory, and microbial perspectives. Through this study, we conducted ethnographic interviews with local producers and laboratory analyses of four locally available samples to examine their proximate composition, sensory characteristics, shelf life, and food safety. Nutrient profiles varied significantly due to differences in ingredients and preparation methods, with protein content ranging from 3.38% to 6.60% and water content from 78.73% to 88.95%. Sensory evaluation revealed varying consumer preferences, influenced by texture and spiciness. Microbial testing identified E. coli and coliforms in several samples, highlighting hygiene concerns in small-scale production. Beyond its nutritional and culinary value, Sambal Tumpang exemplifies sustainable food practices by valorising over-fermented tempeh and holds potential as a functional food and a tool for gastrodiplomacy. This study emphasises the importance of preserving and innovating traditional foods to ensure cultural continuity while addressing contemporary concerns regarding food safety and marketability.