Maize Germ Oil
Maize germ oil is obtained from the maize seedlings which are removed in the production of maize starch. Depending on their origin, these seedlings contain up to 50 percent oil. As this is a by-product, the quantity of maize germ oil produced worldwide is comparatively little compared to other edible oils.
To achieve a high-quality end product, producers must reliably remove gums and waxes, as well as the free fatty acids from the crude oil. Wet winterization, which integrates dewaxing directly in the neutralization process is suitable for this.
Process line for recovering and refining maize germ oil using the example of wet winterization
The crude oil is obtained by pressing the maize seedlings, further oil being extracted from the press cake with the aid of hexane. Whilst a decanter from GEA Westfalia Separator clarifies the press oil, a separator is responsible for separating the hydratable gums from the water degumming process.
The non-hydratable gums, free fatty acids and the waxes are removed in the subsequent wet winterization step. Once another separator has removed the cleaned and washed crude oil from the wash water, the maize germ oil is dried and bleached. As wet winterization cannot remove 100 percent of the waxes, the bleached oil is cooled in a subsequent step and polished by filtration following crystallization. Once the final remaining waxes have been separated in this way, the maize germ oil is absolutely stable to cold and thus suitable even for storage in refrigerators.
In comparison to dewaxing methods which rely exclusively on filtration, combination with separators for wet winterization is much more economical, as far fewer filter aids have to be used and at the same time filter cycles are considerably increased.