Sunflower, Corn and Rice bran oil is to be Dewaxed/Winterised before consumption as it contains high molecular weight wax. The wax makes the oil cloudy.
To obtain very clear quality of oil specially in cold conditions, oil needs to be dewaxed/winterised. If oils stored at low temperatures , waxes, high melting tri glycerides and certain gums may separate as solids from the oil. This leads to an undesirable cloudy appearance , and many consumers may mistakenly think the oil is spoiled.
The steps for the Dewaxing/winterising process are as follows:
The oil is cooled in crystallisers and gradually the crystal formation takes place. Here filter aid is also added.
The oil is then transferred to a maturator where the crystals are allowed to grow. The oil is continuously cooled by the help of glycol water flowing through the coils.
Finally the oil is filtered on hermetic pressure leaf filters to remove the waxes.
For Rice bran oil, Veendeep has developed P P Filters which are more suitable for high wax oil.
The major advantages of this process is :
Single plant can be used for Dewaxing and Winterising.
Optimum care is taken to maintain the formed crystals till filtration.