High quality Australian sultanas are marketed largely on the basis of their light-golden colour and soft skins. Significant browning occurs in sultanas during storage and shipping, which seriously degrades sultana colour as well as overall quality. Whilst the cause of sultana browning during drying has been attributed to polyphenol oxidase (PPO) mediated oxidation of sultana phenolic substrates, the browning which occurs during sultana storage is less well-defined. The occurrence of non-enzymatic Maillard reactions has been suggested by a number of researchers, yet there has been no specific research conducted to elucidate these reactions in sultanas. In this thesis, PPO mediated browning, non-enzymatic Maillard reactions and, to a limited extent, lipid oxidation reactions were examined in two long-term storage trials.