Honeybee (Apis mellifera) as a source of chitosan to enhance mechanical properties of moulded pulp egg boxes

Chitosan has emerged as a sustainable alternative to fossil-fuel-based plastics. While typically sourced from crustaceans, this study investigated whether honeybee corpses from winter colony losses could serve as a source of chitin and subsequently chitosan for papermaking additives. Chitosan (deacetylation degree 87.77 ± 3.25%; molecular weight 22.70 kDa) was extracted and incorporated into wastepaper pulp to produce moulded egg boxes. The performance (tensile index and stretch at break) was compared with control wastepaper egg boxes, those containing crustacean chitosan, manufacturer-provided boxes, and commercial boxes containing synthetic additives. The honeybee chitosan-enhanced egg boxes exhibited one of the highest dry tensile indices (27.92 ± 1.37 N⋅m⋅g⁻¹) and the best wet stretch at break (2.98 ± 0.21%) among all groups. Furthermore, the boxes maintained a water contact angle of 110° for 10 minutes, outperforming the crustacean chitosan and manufacturer boxes. Although an initial process simulation indicates that a dedicated biorefinery is not viable due to high water and harsh chemical consumption, the protocol optimisation for recycling and wastewater management is feasible. Despite techno-economic challenges, the study demonstrates that honeybee-derived chitosan is an effective papermaking additive, highlighting its potential to transform waste into a valuable material.