Sunflower oil refining

Crude sunflower oil is refined, bleached, winterized (dewaxed), and deodorized before being used for edible purposes. The crude oil contains several impurities that must be reduced in order to make the oil suitable for food application. There are two groups of impurities present in the crude sunflower oil  

Crude oil is generally stored in large tanks with capacities up to a few thousand tonnes depending upon the size of the refinery. These tanks have optional heating coils but most of them do not have mechanical agitation. Agitation is beneficial because wax, phospholipids, and moisture tend to settle to the bottom of the tank and this may cause increased refining losses. Crude sunflower oil specifications 

Halpen test Saponification value Unsaponifiables Free fatty acids (as oleic acid) Moisture and volatile Insoluble impurities Lovibond red color Linolenic acid 

121 minimum negative 188-194 1.3% maximum 2.0% maximum 0.5% maximum 0.3% maximum 2.5 maximum 1.0% maximum 

In addition to the above analysis, it is recommended that any refiner of sunflower oil should also check the following micro components because they indicate the true quality of the oil as salad oil or as other finished products such as margarine and shortening. 

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Experiments were carried out using soybean oil, canola oil, refined com oil, refined cottonseed oil, refined sunflower oil, refined palm oil, and refined coconut oil obtained from commercial sources. Biobased lubricant oils used in this study are given in table 14.1. 

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