Optofluidic device to monitor the evolution of liquid products by near infrared spectroscopy (EP3798606) Optofluidic device for analyzing fluids comprising a near-infrared «NIR» light arrangement (8) to provide a light beam, a NIR detector (10) to receive it and to emit a signal (S1) associated with the characteristics of the light beam, an optofluidic cell (2) to house the fluid, variable in size, comprising an illumination window (3) to allow the light beam to pass through, a NIR mirror (4) to receive the light beam and to reflect light in a specific range of wavelengths, an actuator (14) to vary the distance between the illumination window (3) and the NIR mirror (4), an optical arrangement, comprising a first set of optical fibers (6), which connects the NIR light source (8) to the optofluidic cell, and a second set of optical fibers (7), which connects the optofluidic cell (2) to the NIR detector (10), a processing module (16), to analyze the signal (S1) emitted.