Title: Quality and stability of Cuban shark liver oil: Comparison with Icelandic cod liver oil
Abstract
The quality of shark liver oil obtained from a pool of livers of three shark species (Ginglimostoma cirratum, Carcharhinus longimanus, and Carcharhinus falciformis) caught in the Cuban coastal waters was studied by measuring some chemical characteristics such as squalene, vitamins (A, E, D) and free fatty acids. The quantity of some metals (copper and iron) was used as an indicator of the possible oxidation of the oil. As oxidative stability is one of the most important factors in keeping the quality of fish oils, volatile compounds, fatty acids in neutral fraction, peroxide values and induction period were evaluated as stability parameters in shark liver oil, in order to detect oxidative changes during storage. The oil was kept at two different temperatures (0°C and 30°C) for three weeks. Sensory analysis was done to evaluate the rancidity levels of the oil during the storage time. Dioxins and dioxin-like PCBs (polychlorinated biphenyls) are very persistent chemicals responsible for contamination in fish oils. Its content in shark liver oil was also evaluated in this study. Cod liver oil from Gadus morhua and other species of Gadus from South-West Iceland was also evaluated in order to establish a comparison between both oils in terms of quality and stability.