Lupin–wheat bread protein: Modification of the bread matrix for improved health attributes

Nutritional qualities of lupin suggest bread rich in lupin has the potential to provide a number of health benefits. Mixing of lupin flour to wheat has major effects on bread properties including the extractability of proteins that is crucial to define the ultimate attributes of food. Present study investigated the lupin and wheat proteome dynamics as affected by the baking of lupin–wheat bread by using 2-D electrophoresis and direct mass spectrometry. Many of the proteins from both lupin and wheat remained unchanged in baked lupin–wheat bread, while the others were incorporated into the bread matrix and could not be extracted. Most of the alpha-conglutins could be readily extracted from the lupin–wheat bread even at milder extraction. In contrast, most of the beta- conglutins lost extractability. The structural attribute that correlates with this difference in behaviour is the greater in thermal stability of alpha-conglutins relative to Beta- conglutins. Most of the beta and gamma conglutins showed relatively higher peptide sequence coverage of corresponding matched proteins compare to alpha conglutin due to lack of information regarding this group of protein in the database.