Extraction of natural antioxidants from plant sources and food industry or agricultural wastes with classic extraction techniques requires enormous volumes of toxic organic solvents. The use of non-toxic surfactants for the removal of organic substances from wastes in temperatures over the cloud point is considered a promising alternative. Only recently, this technique has started to be exploited for polyphenol, tocopherol, carotenoid, etc. isolation from food industry wastes. This study will examine the possibility of using a food grade surfactant (lecithin) and a cloud point extraction (CPE) procedure for the isolation of value added products (polyphenols) from food industry wastes (olive mill waste water and wine sludge).
Lecithin, which was selected as a relatively low cost surfactant, is a natural product (without a concentration limitation from the Greek Codex Alimentarius). It is also an edible surfactant; therefore no separation of recovered phenolic substances from the micellar system is required. It is also easily separated and a rich in desirable compounds (polyphenols) phase is extracted.
The best results during CPE procedure were achieved when the temperature was maintained at 40°C and pH was adjusted to 3. Otherwise, the total recovery rate of phenolic compounds appeared to be reduced.
The use of multiple CPE steps (1st, 2nd, and 3rd) increases the percentage of total recovery of phenolic compounds. However, whether they will be used depends on both the cost of the surfactant and the available time of the industry. Extracted phenolic substances showed high antioxidant activity.
TEI of West Macedonia
