Jamu waste as liquid organic fertilizer (LOF) and its quality analysis

Jamu is an organic product that is commonly used in Indonesian medicine. The Jamu industry produces by-products called Jamu waste which contains many nutrients. The study aimed to assess the suitability of utilizing Jamu waste to produce liquid organic fertilizer (LOF) by analyzing the nutrients (N, P, K, C-organic). LOF was produced through anaerobic fermentation of a mixture of Jamu waste as substrate, molasses, water, and EM4 under various amounts of EM4 (7.5, 15, and 30 ml) and fermentation time (14, 21, and 28 days). Results revealed that EM4 and fermentation time affected the nutrients of LOF. The highest content of Nitrogen (0.163 %) and Potassium (0.0169 %) was obtained by LOF with 7.5 ml EM4 and 28 days fermentation. Unfortunately, the LOF produced has not met LOF quality standards (2 % N + P + K and minimum 10 % C-organic). Besides EM4 and fermentation time, the substrate also affects LOF quality. As a single substrate, Jamu waste is not enough to produce LOF with high nutrients. This study proposes an additional organic matter with high contents as a substrate to optimize LOF quality.