A method for guaranteeing at least one characteristic of a fluid used for producing food products. This method utilizes a system for piping and delivering the fluid, combined with means for producing the products, in order to use the fluid for producing the products; the measuring a value of the characteristic; the comparing the measured value with a predetermined threshold value; the act of executing an action if the measured value departs from the threshold value; the combining the measured value with first information for identifying at least one product; and then the storing the associated value and the associated information.