Nanofiltration of lactic acid whey prior to spray drying: Scaling up to a semi-industrial scale

- The semi-industrial scale-up of nanofiltered lactic acid whey drying is possible.
- The results are similar to those obtained on a small pilot plant in the laboratory.
- The nanofiltration of lactic acid whey reduces stickiness during drying.
- The nanofiltration of lactic acid whey decreases the hygroscopicity of the powder.

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.