We propose in this paper to use a simple and robust experimental protocol based on longitudinal ultrasonic velocity measurement in order to evaluate the viscosity of coconut water in a cylindrical stainless-steel pipe. Seven samples with Soluble Solids Content (SSC) ranging from 6.7 to 44.2°Brix were studied using conventional Couette viscometry and high-frequency ultrasonic methods. Calibration laws linking the ultrasonic velocity measured at 5¿MHz to the shear viscosity and to the SSC are proposed. These laws are in very good agreement with previous measurements carried out several years ago using a plane 25¿MHz transducer directly introduced into the coconut water with SSC of up to 60°Brix.