Flavour release in model bovine serum albumin/pectin/2-octanone systems

The release of 2-octanone bound by bovine serum albumin (BSA)/pectin complexes in aqueous solutions was induced by shift of pH from neutral (pH 6.4) to acid (pH 4.3). The release of 2-octanone was due to BSA unfolding on the oppositely charged rigid polysaccharide matrix at pHs below BSA's isoelectric point (IEP). The amount of released and freely available flavour was estimated by the effect of 2-octanone on the conformational stability of BSA, i.e. using BSA added to 2-octanone solution as an internal molecular detector. DSC was used to study the effects of: (i) protein denaturation on flavour binding capacity, (ii) binding of flavour on conformational stability of the protein and (iii) to develop an instrumental technique to measure the flavour release. (C) 1998 Elsevier Science Ltd. All rights reserved.