The present invention relates to an improved process for producing hydroxy fatty acids preferably dihydroxy or polyhydroxy acids from unsaturated fatty acids derived from natural oils and fats. A self-capacitance detection can be performed by a sensing device. In response to an interrupt received from the processor at the control point, a determination is made whether the sample point has been reached. Furthermore, using the same steps, an aversive stimulus may be played that elicits an avoidance without a startle reflex.