Ultrafiltration flux of acid whey obtained by lactic acid fermentation

Influence of process temperature and microfiltration pre-treatment on flux and fouling intensity during cross-flow ultrafiltration of sweet whey using ceramic membranes

“…However this appears to be contrary to expectation; the reason why these authors came to their conclusion could be that they worked with small pieces of membrane with little difference in DpTM between inlet and outlet. Several studies also suggested the possible involvement of calcium in fouling mechanisms during filtrations of milk or whey, but did not confirm whether it considerably influenced permeate flux (DuclosOrselloa, Lib, & Ho, 2006;Konrad et al, 2012;Marshall, Munro, & Tr€ agårdh, 2003;Musale & Kulkarni, 1998). According to the results of present study, the influence of calcium was obviously crucial for permeate flux decrease during UF of fresh or MF whey at 50 C.…”

“…Such assumptions, however, were not in complete agreement with results of some previous studies that did not confirm a relation between calcium salts and flux decrease during UF of whey (Musale & Kulkarni, 1998;Ramachandra Rao, 2002). However, Konrad, Kleinschmidt, and Faber (2012) found that removal of Ca-salts resulted in a considerable flux increase during UF of acid whey. Furthermore, the overall flux decrease during UF of fresh (48%) or MF whey (around 30%) was reasonably lower in comparison with the overall flux decline (about 60%) observed during UF of pasteurised whey, regardless of the applied process temperature.…”

The sol–gel transition temperature of skim milk concentrated by microfiltration as affected by pH and protein content

“…Acid whey has a lower pH, less lactose and less total solids, but higher amounts of calcium, phosphorus and lactic acid compared to sweet whey (Schmidt et al 1984). Due to its composition and low pH (4.5 to 4.7; Kessler 2002), processing acid whey causes technological problems such as precipitation of its components during evaporation and drying (Dec and Chojnowski 2006) and low permeation rates due to increased fouling during separation of its components via ultrafiltration (Konrad et al 2012), making acid whey an undesired coproduct. Thus, it seems to be economically necessary to decrease the output of acid whey.…”

Chemical characterisation and application of acid whey in fermented milk

“…Acid whey (pH <5.0) is generated in fresh-type cheese production, which includes acid coagulation of milk, cream or whey, or a combination of acid and rennet or acid and heating and it differs from sweet whey in terms of proteins, minerals and lactose concentrations. It also has higher acidity and calcium content, and the absence of caseinomacropeptide (Konrad et al 2012). Some of the most popular cheeses in which acid whey is a by-product are, Cream Cheese, Cottage, Quark or Tvorog, Fromage frais, Ricotta and Petit Suisse (Schulz-Collins and Senge 2004).…”