Sustainable industrial crop-based strategies for cocoa butter substitutes: advances in plant, microbial, and lipid...

Cocoa butter (CB) is the defining lipid of chocolate, valued for its unique triacylglycerol (TAG) composition and polymorphic behaviour that confer gloss, snap, and rapid melt-in-mouth properties. Increasing volatility in cocoa (Theobroma cacao) supply, driven by climate pressures and rising demand, has intensified interest in cocoa butter substitutes (CBS). This review summarizes recent advances across the main technological routes for CBS development. Conventional sources such as palm mid-fractions and shea butter provide compositional compatibility, while enzymatic interesterification and fractionation can partially reshape TAG profiles towards CB-like structures. Engineered oleaginous yeasts have also been developed to produce CBS lipids through metabolic rewiring and heterologous acyltransferase expression, although economic constraints remain. Plant metabolic engineering has generated seed oils enriched in oleic, stearic, or palmitic acids with reduced polyunsaturated fatty acids. However, reproducing the balanced palmitic-stearic-oleic composition and stereospecific TAG architecture of CB in scalable crop systems remains a major challenge.