On the basis of high-resolution synchrotron powder diffraction data, crystal structures have been solved for 1,3-distearoyl-2-oleoylglycerol, a major cis-mono-unsaturated triglyceride fraction of cocoa butter, and cocoa butter itself in the beta(V) phase. The latter implies that in fact a crystal structure model of chocolate in the beta(V) phase has been obtained. The results clarify the metastability of the beta(V) phase and explain why fat bloom may develop on beta(V)-type chocolate that has been stored at temperatures that are too high.