Investigation into the packaging and operation of an electronic tongue sensor for industrial applications

Abstract

PurposeThe purpose of this paper is to describe the packaging and operation of an electronic tongue sensor. The sensor will be used in an industrial setting and the packaging needs to withstand the harsh clean‐in‐place (CIP) routines that are commonly employed. A suitable epoxy, Loctite FP4450 HYSOL, was identified from a number of packaging materials. The sensor was validated by carrying out cyclic voltammetry in a number of reference solutions including sulphuric acid solution and ferrocyanide in potassium chloride solution, which gave well‐defined reduction and oxidation peaks that could be compared with the literature. The operation of the sensor in mixtures of salt and citric acid solutions was also investigated and it was seen that by applying a carefully selected voltage window and scan rate to each electrode, the sensor could distinguish between the different mixtures. Further experimentation and the application of principle component analysis have shown the sensor to have good repeatability.Design/methodology/approachThis paper concentrates on the ability of the sensor packaging to withstand a typical industrial CIP procedure. A number of packaging materials are investigated. In addition, the operation of the sensor has been investigated by using cyclic voltammetry.FindingsOne successful packaging material is Loctite 9461A&B HYSOL. Poly ether ether ketone also performs well after repeated CIP exposure. For ease of manufacture, Loctite FP4450 HYSOL is the epoxy of choice. An extensive matrix of test solutions was prepared from salt and citric acid powders. The aim was to investigate the sensor's ability to distinguish between increasing concentration levels of salt and citric acid and also to investigate how the sensor operates in mixtures of the solutions. By carefully choosing the applied voltage window and scan rate, the electrodes can distinguish between the mixturesOriginality/valueThis research work has highlighted a robust packaging material to withstand industrial CIP procedures.