Abstract
Foam fractionation can be used to enrich a hydrophobic protein such as bromelain from an aerated dilute protein solution because the protein foams. On the other hand, a protein such as invertase, which is hydrophilic, is not likely to foam under similar aerated conditions. While a foam fractionation process may not be appropriate for recovering a hydrophilic protein alone, it is of interest to see how that non-foaming protein affects the foaming protein when the two are together in a mixture. The bromelain enrichment, activity and mass recovery were observed as a function of the solution pH in order to explore how invertase can affect the recovery of bromelain in a foam fractionation process.