Effect of Cottage Cheese Whey Pretreatment and 2‐phase Crossflow Microfiltration/Ultrafiltration on Permeate Flux and Composition

The effect of chemical pretreatment with calcium chloride and ethylene diamine tetraacetic acid (EDTA) in combination with 2‐phase crossflow microfiltration and ultrafiltration was studied. Solutions of untreated and chemically treated whey were microfiltered at 3 flow rates, with 0%, 10%, and 20% air injection. Significant increases (p < 0.05) in flux were found for untreated and EDTA treated whey at 10 L/min when 20% air was applied. Microfiltration permeates also had a higher (p < 0.05) protein concentration at this flow rate when air was used. Ultrafiltration of the microfiltration permeates resulted in no difference (p < 0.05) between the flux of untreated permeate ultrafiltered with 20% air and calcium chloride treated whey permeate with 0% air injection. This suggests that 2‐phase flow with air injection could be used to increase the efficiency of both the microfiltration and ultrafiltration of whey and chemical pretreatment could be minimized.