Internode-specific susceptibility of sugarcane to post-harvest changes during harvest-to-crush delay in the Kwa-Zulu Natal Midlands. Part I: Green whole stalk cane

Abstract

The occurrence of supply chain management bottlenecks in the sugarcane industry is the major cause of post-harvest changes resulting in sucrose degradation during harvest-to-crush delay. The present work reports the post-harvest quality changes in green harvested sugarcane, during a nine-day harvest-to-crush delay from the Kwa-Zulu Natal Midlands in South Africa. The total soluble solids (TSS), respiration rate, total bacterial count (TBC), and lactic acid (LA) concentrations were examined for internode-specific susceptibility to deterioration across the stems. There were significant increases in TSS in the top internodes implying the incidence of comparatively high physiological changes in these portions. For respiration rates, the trends were similar in the two outermost portions in contrast to the middle portions. Carbon dioxide levels were highest in the top internodes and least in the middle portions. Similarly, for TBC, out of the two cut ends, the top portions sustained higher populations. LA was only detectable in the outermost portions starting from day 5 in N12 and day 7 in N31, respectively. The findings of this study showed that there is a variation in the rate of post-harvest changes sustained in the different internodes of a stalk. Thus, development of indices to detect deterioration signals during harvest-to-crush delay, in the high sucrose environment of the sugarcane stem, should consider this differential rate of postharvest metabolic change of harvested whole stalks.