Performance Evaluation of Ceramic Membrane on Ultrafiltration and Diafiltration Modes for Efficient Recovery of Whey Protein

The recovery of high-quality, valuable end products from cheese whey is a very important industrial process. The aim of this study is to improve the recovered protein content of concentrate stream in cheese whey. The experiments were conducted by using ceramic ultrafiltration (UF) membrane followed by diafiltration (DF) process with a 15kDa molecular weight cut-off (MWCO). The volume concentration factor (VCF) was set as 1.4, 2.0 and 3.3 by controlling the permeate and concentrate volume. It was observed that the protein concentration increased from 1.4 g/l in the feed solution to 9.9 g/l in the concentrate stream. After VCF optimization, two intermittent feed diafiltration (IFD) cycles were performed experimentally and a mathematical model with real-time function was applied for DF yield calculation. The maximum yield was found as 88% at the end of the second DF cycle. The protein content reached to 33% in the concentrate stream after applying the IFD process. During the fouling experiments of DF process, the indicative parameters were calculated with three different fouling models. Total resistance (RT), membrane fouling index (MFI), and unified membrane fouling index (UMFI) were found as 5.15x1014 m-1, 25x106, and 344 respectively. IFD process enhanced the overall performance of whey processing compared to normal UF process.