Technical Abstract: A review of sugarcane deterioration that detrimentally affects processing in the United States (US) and South Africa (SA) is presented. Postharvest sugarcane deterioration products are dependent on sugarcane injury, environmental conditions, variety, cut-to-crush delays, and extent of adventitious infection. When compared to the US, particularly Louisiana, the South African sugar growing region is geographically and climatically varied and dispersed, with a much longer processing season and many regional differences. Sugarcane management and harvesting methods also differ. Leuconostoc infections (resulting in formation of dextran, mannitol and lactic acid and to a lesser extent acetic acid, ethanol and carbon dioxide) have been considered the main cause of factory processing difficulties when handling deteriorated sugarcane. The high humidity and temperatures early in the three month sugarcane processing season in Louisiana, as well as late season winter freezes, are conducive to the formation of this viscous glucopolysaccharide. Dextran was seldom present in South African raw sugar. In the past 10 to 15 years, cane with higher dextran concentrations have been entering some factories, especially in the KwaZulu-Natal Midlands region, and have detrimentally impacted sugar quality. Unfortunately, current methods to determine dextran at the factory all have drawbacks. The effects on processing of other major degradation products that have been monitored (eg mannitol, lactic acid, kestoses and ethanol) will be discussed in this review.