Mineral Paraffins in Vegetable Oils and Refinery By-Products for Animal Feeds

摘要

Raw vegetable oils often contain mineral paraffins with 10-40 carbon atoms at concentrations of 30-150 mg/kg, of which around a third remains in the oil after deodorization. The presence, concentrations, and compositions of the contami- nant(s) seem to be irregular, suggesting several (largely unknown) sources. Toxicity of the contamination cannot be assessed as long as the material, of which the mineral paraffins analyzed are part, is unknown. Raffination of edible oils yields by-products consisting of free fatty acids and the condensate of the deodorization process. These were usually used for the production of mixed animal feed (possibly after extraction of some valuable components), but they commonly contain 200-3000 mg/kg of mineral paraffins, which by far exceeds the Swiss limit of 30 mg/kg. These paraffins are stripped from the raw vegetable oils for human consumption during deodorization and are enriched in the fatty acids used for washing the effluent stream.