Identification of sterene compounds produced during the processing of edible oils

Abstract

Abstract Samples of maize, rapeseed, soyabean, sunflower, and palm oils, collected at different stages in their respective refining processes, have been analyzed for the presence of dehydrated sterols (sterenes). A total of fifteen compounds were detected. Four have been characterized using model systems designed to investigate their formation. Their elemental composition, and that of the other eleven sterenes, was determined by high resolution mass spectrometry and structures assigned to a further six compounds. These included the ‐3,5‐, ‐2,5‐, ‐4,6‐,‐3,5,22‐, and ‐4,6,22‐ sterenes. Sterenes were not present in crude or alkali neutralized oils. Bleaching introduced a maximum concentration of 5 μg g −1 of total sterenes into the edible oils. Deodorization is the dominant stage in sterene production resulting in a maximum total concentration of 163 μg g −1 . This increased concentration arises due to dehydration of the sterols and considerable isomerism of the sterenes.