*2.3. The Effect of Whey Type on Pigment Production*

Whey powder (W), demineralized whey powder (DM), deproteinized whey powder (DP), treated deproteinized raw whey powder (DPW), and treated deproteinized demineralized whey powder (DPDM) were used as fermentation substrate. Initial concentration of lactose was 50 g/L for each fermentation. DM and W samples were subjected to deproteinization to obtain DPW and DPDM. The process of deproteinization was adapted from Roukas et al., [38]; the pH of W and DM were adjusted to 5.0 and protein precipitation was induced by heating W and DM solutions at 90 ◦C for 20 min. The solutions were kept at room temperature for 1 h and precipitated proteins were removed by centrifugation (Hettich Universal 320 R, Tuttlingen, Germany) at 6000× *g* for 15 min.
