Molecular analysis of the beta-polymorphic form of trielaidin: crystal structure at low temperature

This work reports on the structure of trielaidin [EEE, 1,2,3-tri(trans-9-oc tadecenoyl)glycerol], a trans unsaturated triglyceride present in many refi ned fatty materials (margarines, chocolate products etc.). Firstly, the pol ymorphism, i.e. the existence of different crystalline forms at various tem perature ranges, was defined. Secondly, the crystal growth was examined. By developing a particular growing system, monocrystals of the most stable po lymorphic form, i.e. the beta-form, were obtained. To reduce thermal vibrat ions the X-ray data were collected at low temperature (173 K) and the struc ture was solved using direct methods. The structure was then analyzed in te rms of conformation and crystal packing and compared with those of the othe r known triglycerides.