Improving quality of refined canola oil byliquid–liquidextraction on pilot scale apparatus

Abstract

AbstractThe aim of this work was to refine expeller‐pressed crude canola oil by pilot scale liquid–liquid extraction with hydrated ethanol as solvent. Quality indices were determined, and shelf life was estimated in the accelerated test. The scale projection was performed based on the results of the pilot scale. The experimental device operates in a batch process with 89.6% yield deacidification and an average of 4.4 contacts per assay. In this process, without bleaching and deodorization steps, physicochemical parameters were according to theCodex Alimentariusstandards, except moisture. In this way, it will be necessary to apply nonthermal techniques to remove water. The major fatty acids identified were oleic and linoleic acid and the absence of trans fatty acids. For the shelf life, the refined oil presented free fatty acids 0.28% and peroxide value 12.65 meq O2kg−1after 24 hr at 65°C. The pilot scale results showed that the technique is suitable to produce edible oils. A liquid–liquid extractor was designed for industrial scale with the total volume will be 12,000 L. To process 6 tons of crude canola oil per day, the unit will be able to produce 1.3 thousand tons per year of refined canola oil.Practical applicationsAfter acid degumming, canola oil was submitted to liquid–liquid extraction, using ethanol as solvent. As a result, two traditional steps of refining vegetable oils have been eliminated: bleaching and deodorization. This fact directly impacts on physical space of industry, maintenance of equipment and need for operators.Transfats were not detected in canola oil, pointing that the technique is efficient in the production of healthier oils, with less environmental impact.