Laboratory scale Clean‐in‐Place studies on the effectiveness of caustic and electrolysed water on the removal of dairy soils

Abstract

The present study was conducted to evaluate the efficacy of electrochemically generated, ready‐to‐use dilute solution of sodium hydroxide (0.04%) (eNaOH) against dairy soils in a Clean‐in‐Place (CIP) process of a model ultra‐high temperature (UHT) system. The UHT system was fabricated using 306 stainless steel material and comprised of a collection tank, processing tank with an oil bath, chiller bath, centrifugal pump, and the control panel. Milk deposition was obtained by repeatedly re‐circulating milk through the system and thereafter cleaning it using different solutions. Different physico‐chemical parameters were investigated. The pH of the exiting solution remained within the range of 6–8.5 for eNaOH solution relative to 9–13 for 1% sodium hydroxide (NaOH) solution. The turbidity of the exit wash declined only slightly when using eNaOH as opposed to logarithmic decline when using 1% NaOH. Inductively Coupled Plasma analysis showed an increased affinity of Ca (45%–51%) and Mg (81%–96%) toward eNaOH solution relative to 1% NaOH. Overall, the findings of this study suggest eNaOH as a possible alternative to increased longevity of food processing equipment and reduced occurrence of scaling.Practical applicationsThe current study provides an alternative cleaning solution to the dairy industry with better cleaning efficiency at 1/25th concentration of the current cleaning process. Electrolytically generated sodium hydroxide solution (eNaOH) at 0.04% is a non‐toxic, non‐corrosive, environmentally friendly solution that has shown to give promising results at 60°C as compared to 1% NaOH at 70°C. Inductively Coupled Plasma analysis showed an increased affinity of Ca (45%–51%) and Mg (81%–96%) toward eNaOH solution relative to 1% NaOH. Overall, the findings of this study suggest a possible alternative to increased longevity of food processing equipment and reduced occurrence of scaling.