A flow control apparatus adapted to receive a feeding set includes a housing capable of receiving at least a portion of the feeding set. A pumping device is supported by the housing and positioned to contact the feeding set when the feeding set is received by the housing so the pumping device acts on the feeding set to produce fluid flow in the feeding set for delivery of fluid to a subject. An ultrasonic sensor is supported by the housing and arranged with respect to the pumping device to produce a sensor signal indicative of a viscosity of the fluid delivered through the feeding set. A control circuit is in communication with the ultrasonic sensor for receiving the sensor signal from the sensor indicative of the viscosity of the fluid and in communication with the pumping device to control operation thereof.
