Edible Oil Refining Line INTRODUCTION
An edible oil refining line is a continuous, automated series of processes and equipment designed to convert crude vegetable oil (extracted from seeds like soybean, rapeseed, sunflower, palm, etc.) into a clear, stable, palatable, and safe product for human consumption.
Crude oil contains various impurities that are undesirable for taste, appearance, shelf-life, and health. The refining process removes these impurities while preserving the nutritional value (like natural tocopherols/Vitamin E) and minimizing oil loss.
The Main Steps in a Continuous Refining Line
A standard continuous physical refining line consists of the following stages, typically arranged in sequence:
1. Degumming
To remove hydratable and non-hydratable phospholipids (gums).
2. Neutralization (Deacidification)
This is the major step that differentiates the two primary refining methods.
A) Chemical Refining (Alkali Neutralization):
B) Physical Refining (Steam Stripping):
3. Bleaching
To adsorb color pigments, oxidation products, traces of soap, and metals.
4. Deodorization
To remove volatile compounds that cause off-odors and flavors. This is also the stage where FFA are removed in physical refining.
5. Winterization (Dewaxing) - Optional Step
Required for some oils like sunflower or rice bran oil that contain natural waxes. These waxes crystallize at refrigerator temperatures, making the oil cloudy.
