A new study published in Biofuels, Bioproducts and Biorefining highlights an innovative approach to transforming apple pomace—an often-discarded by-product of apple processing—into valuable bioethanol and animal feed ingredients. Apple pomace, which represents 25–30% of processed apples, is typically treated as waste despite its rich carbohydrate content and strong potential for bioconversion.
The research evaluates how this abundant agro‑industrial residue can be effectively valorized through two bioconversion pathways: separate hydrolysis and fermentation (SHF) and simultaneous saccharification and fermentation (SSF). Thanks to its natural composition—high in cellulose, pectin, and hemicellulose—apple pomace proves to be a promising substrate for enzymatic saccharification and alcohol fermentation.
The study's findings reveal distinct advantages in the resulting fermentation residues:
- SHF residues exhibited higher fiber levels, making them well‑suited for formulating diets that require resistant fiber sources.
- SSF residues contained lower fiber but higher protein and reduced lipid content, offering a more digestible option ideal for high-producing ruminants and poultry.
By demonstrating the dual value of apple pomace in renewable energy production and nutrition, the study emphasizes a practical, sustainable solution to reduce waste and enhance circularity within the food and agricultural sectors.
Luciane M. Colla, lead author of the study, said "This article is important because it presents an alternative to an agro-industrial waste product, optimizing the process of obtaining bioethanol through different methodologies. The use of waste allows for its valorization, in addition to preventing environmental contamination."
