Co-crystallisation with Sucrose as a Food-grade Encapsulation Strategy for Bioactive Compounds: Mechanisms, Evidence and Translational Priorities

Abstract

Co-crystallisation with sucrose converts a supersaturated sugar syrup into porous microcrystalline agglomerates while incorporating a food ingredient or bioactive-rich phase. The approach is attractive because sucrose is familiar, inexpensive, readily soluble and compatible with many foods, yet its scientific basis and practical value are often overstated by treating all sucrose-bioactive products as molecular co-crystals or by equating analytical entrapment with proven biological delivery. This critical narrative review evaluates the evidence for sucrose co-crystallisation as a food-grade encapsulation strategy, with emphasis on process-structure-property relationships, protection of labile compounds, ingredient functionality, food-system performance and scale-up constraints. Literature published from 1988 to 9 June 2026 was identified through accessible scholarly indexes and citation searching, and was critically appraised for formulation transparency, structural characterisation, active-specific analysis, storage design, comparator quality and translational relevance. The evidence consistently shows that rapid sucrose crystallisation can transform liquids, extracts, oleoresins and micronutrients into dry, dispersible powders or compressible granules while preserving a largely crystalline sucrose framework. Protection is nevertheless conditional: matrix porosity, residual moisture, relative humidity, oxygen, light, bioactive chemistry, core loading and co-matrix materials can dominate stability. Hydrocolloids and protein carriers often improve retention, whereas high loads of non-sucrose solutes can reduce crystallinity and flowability. Recent studies extend the platform from single botanical extracts towards co-encapsulation, by-product valorisation and application in meat, confectionery, gelatin and beverage models. Evidence for gastrointestinal bioaccessibility, human bioavailability, long-term industrial shelf life and continuous manufacturing remains limited. Co-crystallisation is therefore best regarded as a particle-engineering and ingredient-integration platform rather than a universally protective encapsulation technology. Future progress depends on mechanistic structural analysis, standardised performance metrics, realistic food-matrix validation, moisture- and oxygen-aware packaging studies, nutritional reformulation, and pilot-scale mass and energy balances.