Summary
- A review published on 24 August 2026 collects the routes for recovering value from cassava processing residues: peels, bagasse, leaves, stems and wastewater
- These residues are rich in starch, fibre and lignocellulosic components, yet the authors describe them as largely underutilised
- Hydrothermal pretreatment offers the best balance between efficiency and the formation of inhibitors
- Acid pretreatment maximises hemicellulose solubilisation but generates higher levels of toxic compounds, while alkaline routes delignify effectively but produce effluents needing further treatment
- Possible end products include bioethanol, biogas, biohydrogen and organic acids
The residues nobody uses fully
According to PubMed, a team led by Tammires L. C. Santana of the State University of Feira de Santana in Bahia, Brazil, with Jude A. Onwudili of Aston University in the United Kingdom, alongside Carine T. Alves and Taíse B. de Jesus, published this review in RSC Advances on 24 August 2026.
The authors note that cassava is a key tropical crop whose processing generates large volumes of residues — peels, bagasse, leaves, stems and wastewater. Those streams carry high biotechnological potential but remain largely unexploited.
Comparing the pretreatment routes
| Route | Strength | Limitation |
|---|---|---|
| Hydrothermal | Balanced efficiency versus inhibitor formation | — |
| Acid | Maximises hemicellulose solubilisation | Generates higher levels of toxic compounds |
| Alkaline | Effective delignification, better enzyme access | Effluents require further treatment |
| Biological and enzymatic | Environmental advantages, low inhibitor formation | Slower kinetics |
The authors also cover emerging technologies such as ultrasound and non-thermal plasma, which show promise for improving sugar release and reducing hydrolysate toxicity, though few studies focus specifically on cassava residues.
The main conclusion
The review concludes that integrating complementary routes is a more robust strategy than choosing a single method, in order to maximise production of bioethanol, biogas, biohydrogen and organic acids.
The biorefinery models the authors reviewed consistently show significant energy gains and reduced environmental impacts, supporting the view that cassava residues are a strategic platform for circular economy applications.
Converting starch mill wastewater into biogas is one of the routes this review covers. You can read about our own environmental programme on our sustainability page.
Sources:
- Article metadata retrieved from PubMed: Santana T.L.C., Onwudili J.A., Alves C.T., de Jesus T.B. “A comprehensive review of methods for valorisation and production of bioproducts from various cassava wastes.” RSC Advances, 24 Aug 2026, PMID 42639357 — DOI