Post-harvest quality of stored sugarcane stalks and their reflection on the production of cane spirit

Summary

This research aimed to evaluate the technological and microbiological characteristics of the juice produced from harvested and stored sugarcane, and the reflections on the fermentative processes and formation of secondary compounds and contaminants in the production of cane spirit. After harvesting, the sugarcane stalks were stored at environmental temperature (20-32 °C) for 0, 24, 48, 72, and 96 hours, the must being prepared soon after juice extraction. The fermentations were carried out using a batch process with five fermentative cycles, distilling the wine in a copper still. The technological and microbiological characteristics of the juice and the fermentation process were analysed. Storage of the cane stalks caused significant losses in the technological quality of the juice, negatively influencing the fermentative process, and decreasing the viability of the yeast cells and shoots. The use of raw material stored for periods longer than 48 hours contributed to a reduction in pH, increase in total acidity and increase in residual reducing sugars in the wines, reflecting in reduced alcohol production. The levels of volatile acidity, ethyl acetate, acetaldehyde, copper, methanol and ethyl carbamate in the cane spirits were within the limits established by Brazilian law, whilst the higher alcohols and furfural contents were high in the distillates produced from harvested and stored sugarcane.

Keywords:
Raw material; Storage; Fermentative process; Chemical composition