Nanofiltration of lactic acid whey prior to spray drying: Scaling up to a semi-industrial scale
Résumé
Along with the increase in the fresh cheese production market, there is a concomitant increase in the
volume of its by-product, lactic acid whey (LAW). This type of whey is especially rich in organic acids and
ash content, making it more difficult to develop applications for human food. In view of its hygroscopicity,
this type of whey is in fact clearly the most difficult to dry properly, and its high level of mineralization
narrows its potential uses for nutritional reasons. The aim of this study was to evaluate the
ability to use nanofiltration (NF) for the production of partially demineralized LAW powder with regard
to the dryability of the concentrate and the quality of the powder at a semi-industrial scale. The strong
selectivity of this demineralization process results in a 30% reduction in lactic acid content and a
reduction of between 46 and 60% in monovalent ions. The dryability of the NF LAW concentrate is
improved as well. Moreover, the energy cost of the overall process is reduced by 43%. These elements
highlight the benefit of inserting an industrial NF step into the overall processing of LAW and should
significantly contribute to the production of partially demineralized LAW powder.