Stabilisation of evaporation and spray drying processes with municipal or reverse osmosis water as an entry point for chlorate during manufacture of skim milk powder

Abstract

Chlorate is a concern in the food and beverage industry, associated with chlorine sanitisers in industrial processing and water treatment. This study monitored chlorate entry and accumulation points during skim milk evaporation and spray drying when using municipal and reverse osmosis water to stabilise processing equipment. Municipal water was associated with a 9.2 ± 1.7 and 6.6 ± 1.4 fold increase in chlorate on a dry matter basis during the initial transition from water to product for evaporation and spray drying, respectively. This was not observed when the equipment was stabilised with reverse osmosis water, but could vary depending on the time taken to stabilise processing equipment. Once equipment was in a steady state, there was no entry of chlorate into the finished product for processes stabilised using either water sources; the main points of concern are transitionary periods of operation linked to co-mixing of the product and water.