EFFECT OF ASCORBIC ACID, DIKETOGULONIC ACID AND DEHYDROASCORBIC ACID ON BOVINE SERUM ALBUMIN ON STORAGE IN THE GLASSY STATE

Document Type : Regular Paper

Authors

Department of Food Science and Technology, School of Agriculture, Shiraz University, Shiraz, I. R. Iran

Abstract

Showing the occurrence of glass/rubber transition in bovine serum albumin (a globular protein) at
low moisture levels and the occurrence of Maillard crosslinking in gelatin in previous works, the importance
of the state of glass or rubber of BSA on the rate and extent of polymerisation, protein solubility, colour and
SDS PAGE patterns in the presence and absence of ascorbic acid, diketogulonic acid and dehydroascorbic
acid was investigated. BSA on storage with Ascorbic acid and its degradation products at low moisture
contents (8.3% and 19.1%) at a relatively low temperature (40ºC) can undergo chemical changes resulting in marked increase in molecular weight, solubility decrease and formation of browning colour. The glassy state data established the occurrence of chemical changes (Maillard crosslinking and disulfide crosslinking) in the BSA system on storage below its glass transition temperature.

Keywords