Process Duration and Water Consumption in a Variable Volume Diafiltration for Partial Demineralization and Concentration of Acid Whey

Abstract

Process duration and fresh water consumption were determined (experimentally and statistically) for variable volume diafiltration (VVD) of cottage cheese through a flat sheet membrane (0.046 m 2 ). The VVD process was performed at two volume decreasing ratios (a ¼ 0.75 and a ¼ 0.5). The VVD-0.75 process lasts much longer than the VVD-0.5 process if the same concentration degree is required. The VVD-0.5 process lasts longer than the VVD-0.75 process if it is aimed to achieve the same purification degree. At low purification degrees, both processes require similar quantities of fresh water, but better demineralization is possible after higher dilution, which is typical of the VVD-0.75 process. The mathematical model applied in estimating the duration of the process proved very accurate, which cannot be said about the fresh water consumption model.

Removal of lactate from acid whey using nanofiltration

“…Nanofiltration(NF) membrane technology is already extensively used in the dairy industry to demineralise and concentrate sweet whey streams prior to spray drying (Kentish and Rice, 2015;Okawa et al, 2015;Rice et al, 2009). NF has also been considered at laboratory scale for demineralisation of acid whey (Kelly and Kelly, 1995;Roman et al, 2010;Roman et al, 2009;Vasiljevic and Jelen, 2000). NF is also used for the recovery of lactic acid from fermentation broths where the lactate concentration is 10-20 times that in acid whey (Bouchoux et al, 2006;Li, 2006;Sikder et al, 2012;Wang et al, 2013).…”