Temperature-controlled gelation of casein concentrates enabled by the utilisation of acid whey permeate as a diafiltration medium in microfiltration

In this study, ultrafiltration permeate obtained from acid whey (AWP) was applied as a diafiltration (DF) medium during skim milk microfiltration. The thereby induced acidification of differently concentrated retentates was assessed regarding suitability to generate gels from micellar casein concentrates further downstream. While aggregation was avoided during cold DF, subsequent heating induced controlled spontaneous formation of gels with concentration- and pH-dependent firmness ranging from 26 to 1420 Pa. By employing its typical compounds, AWP as a rather problematic dairy side stream could thus be utilised for the production of calcium-rich acidic casein gels providing sensory characteristics of cultured dairy products.