| Abstract: | The foaming properties of bovine β‐lactoglobulin (BLG( BNPS‐skatole (2‐(2′‐nitrophenylsulfenyl)‐3‐methyl‐3′‐bromoindolenine) (BNPS( trypsin (T) and pepsin in 25, 30 and 40% ethanol (P25, P30, P40) hydrolysates were investigated in the 0.2 to 1 mg/ml range. Foaming capacity and foam stability were assessed in terms of drained liquid volume and foam volume. Foam texture was analyzed from video images obtained during foam decay. The foaming capacity of BNPS, P30 and P40 was similar to that of BLG and greater than that of T or P25. All hydrolysates except BNPS were less stable than BLG at all concentrations tested. This result was insured by texture analysis. Principal component analysis confirmed the distribution of the samples into three groups based on their increasing stability: (i): P25, (ii): P30 and P40, and (iii): BLG and BNPS. Tryptic hydrolysate had the poorest foaming properties. The results are considered in relation to the molecular characteristics of the peptides, particularly their size and hydrophobicity. |
