Disulphide interchange in cereal proteins

Abstract

Abstract A method of measuring the extent of disulphide interchange between a model compound, cystamine, and cereal flour proteins has been applied to wheat, steamed wheat, rye, barley and maize. The results indicate that, if the extent of protein‐protein S.S interchange is of the same order as that found in the model reaction, it is several times greater in wheat than the calculated minimum necessary to create a continuous protein network. In the case of rye the extent seems to be sufficient to just comply with this minimum condition. Steamed wheat, barley and maize (none of which can form doughs) fall below the limiting extent of interchange required. It has been assumed that insoluble proteins are precluded from taking part in protein‐protein S.S interchange reactions, and evidence from the literature has been cited to support this.