Study and Comparison of Nutrients in Coffee Grounds Fermented Water Treated with Pulsed Electric Fields.

This study compared the quality of coffee ground fermented liquid (CGFL) with and without pulsed electric field (PEF) treatment on the growth of mung bean seedlings.CGFL was prepared by fermenting coffee grounds with water for 10 days, with one batch treated with PEF (6 kV/cm, 1 Hz, 300 pulses) prior to fermentation.Chemical analysis showed PEF treatment reduced organic matter, organic carbon and total nitrogen by 14-17%, while increasing some mineral contents like potassium and sulfur.Both CGFLs had suitable carbon-to-nitrogen ratios (33-34) for plant growth.Mung beans were grown in soil mixed with the two types of CGFL.This suggests PEF treatment could improve the fertilizer quality of coffee ground waste for agricultural application.