Table 2. Phospholipid content of polar lipid-enriched fraction after ethanol extraction from butter serum and whey serum

Serum	Butter serum powder A (%)	Butter serum powder B (%)	WPC60 (%)	WPC70 (%)
PL	36.7±1.8	45.1±3.5	30.5±1.8	31.0±0.9
Glycolipids	8.6±0.8	1.6±0.1	5.4±0.2	7.0±0.2
Lactose	5.1±1.3	7.5±0.9	ND	ND
Crude protein	7.6±0.6	9.7±0.9	5.0±0.6	5.4±0.4
Yield	21.0±1.1	12.0±0.8	20.0±0.9	18.0±0.6

Polar lipid-enriched fraction was obtained by adding 95% ethanol 7 times to the serum during a 1 h extraction at 25°C.
WPC, whey protein concentrate; ND, not detected.