Sustainable stabilisation of microcrystalline cellulose oil-in-water Pickering emulsions

This study presents the development and characterisation of novel organic Pickering emulsions (PEs) stabilised by microcrystalline cellulose (MCC), aiming to offer a sustainable, biocompatible, and cost-effective alternative to conventional stabilisers. Emulsions were formulated with almond oil (20:80 O/W ratio) and produced using a rotor-stator homogeniser. The stabilising performance of MCC was compared against hydroxyapatite (inorganic PEs) and soy lecithin (traditional emulsion). MCC particles were pre-treated by ultrasound to enhance dispersibility and emulsion stability. The MCC-based PE demonstrated excellent long-term stability, maintaining droplet structure and size over 60 days of storage at room temperature. Rheological analysis confirmed a solid-like viscoelastic behaviour, attributed to a dual stabilisation mechanism involving particle adsorption and network formation. In contrast, lecithin emulsions exhibited rapid destabilisation and a liquid-like rheological profile, while hydroxyapatite PEs showed good stability but lower biocompatibility. This work confirms the high potential of MCC as a scalable and sustainable stabiliser for particle-based emulsions, reducing reliance on nanocellulose and enabling formulation of greener emulsions for diverse applications. • MCC is a sustainable stabiliser for Pickering emulsions. • MCC-based PE has demonstrated excellent long-term stability. • Rheological analysis shows a solid-like viscoelastic behaviour for PE. • MCC was compared with HAp in terms of stabilising performance. • PEs offer longer stability and are a green alternative to traditional emulsions.