Analyses of marine-derived tocopherol in processed foods containing fish

The contents of marine-derived tocopherol (MDT) and other types of tocopherols in processed foods containing fish were analysed. Almost all the processed foods contained MDT, and the %MDT values, calculated using the equation 100 × [MDT]/([MDT] + [α-tocopherol]), where [MDT] and [α-tocopherol] are the contents of MDT and α-tocopherol, respectively, ranged from 0% to 19%. The %MDT values of the processed foods were nearly identical to those of raw fish meat (0–20%). The heat-resistance characteristics of MDT in fish meat treated with three heating processes, boiling, grilling and frying were investigated. All heating processes brought about a decrease in the MDT and α-tocopherol contents and the rate at which the contents of MDT and α-tocopherol decreased were similar across the heating processes. The heat-resistance characteristics of MDT are thought to be similar to those of α-tocopherol. The study results indicate that processed foods containing fish may also influence the MDT content in the human body.