Residual fat (RF) in products made from separated whey is detrimental for shelf life and functional applications. Objective of this study was to remove RF present in whey without utilizing microfiltration. We believe that, by demineralizing the whey via ultrafiltration, RF can be precipitated with denatured proteins and removed by centrifugation. Extensive demineralization can remove enough Ca for the resulting isolate to be heat stable. Trials were run to evaluate the effects that protein concentration (PC), pH and conductivity (CN) have on extent of RF sedimentation. Two demineralized UF retentates (UF-r) were produced from liquid sweet whey protein concentrate (WPC) 60 and 30. Respective UF-r had total solids of 8% and 5.3%; their conductivities were ~400 and ~300mS/cm. Demineralization was achieved by acidifying liquid WPCs to pH 4.5 using HCl and ultrafiltering them along with extensive diafiltration using acidified water. The UF-r were adjusted to different protein concentrations (ctrl, 5, 4, 3, 2.5, 2, 1.5%), centrifuged (for 10 min) and turbidity of the supernatant was measured (n = 2) to understand the effect of PC on RF sedimentation. The drop in turbidity (before and after centrifugation) increased with increasing PC which indicates that preconcentration of whey to about ~3% would be necessary for better sedimentation. Conductivity of UF-r was then adjusted to different levels (ctrl, 500, 750, 1000, 1250, 1500, 1750 μS/cm) and tests were repeated to understand effect of CN on RF sedimentation. Sedimentation increased with decreasing CN with maximum RF sedimentation occurring below 500 μS/cm. Similar trials were conducted for different pH levels (4.1, 4.3, 4.5, 4.7, 4.9) and max sedimentation occurred between 4.5 and 4.7. It appears that lipids in UF-r can be sedimented with conditions near the isoelectric pH of denatured proteins and the relatively low conductivity achieved by UF demineralization. Future work will determine the compositions of the sediment and supernatant to better understand the process and then scale it up to generate pilot scale WPI powder.