In-Depth Vegetable Oil Refining Process for Human Consumption

Every food that you consume has vegetable oil as its prime ingredient. Hence, fats and edible oils are crucial components of the human diet. However, edible oils are not readily found in the purest form as you may think. It undergoes several processes to reach the market for you to buy. Vegetable oil refinery technologically treats the oil so you can consume it directly or add it to your food. 

Soybean, palm, rapeseed, sunflower, corn, and olive are popular sources of vegetable oils that undergo solvent extraction or mechanical expelling. Refining plays a crucial role in removing contaminants and harmful substances to create a healthier version and add to the aroma and finer taste of the oil. This article will explore every step in the process of vegetable oil refining. 

Deep Dive into the Process of Vegetable Oil Refining 

The establishment of a vegetable oil refinery plant offers numerous benefits and promotes economic and personal growth. Vegetable oil partakes in several aspects of human life besides food. It forms a crucial component of cosmetics, medicines, health supplements, research, etc. To further understand the journey of this precious oil, let us examine the edible oil refining process.

Degumming

Mucilaginous gums, or just gums, refer to components like metals, phospholipids, and lecithins found in vegetable oils. The degumming process for edible oil includes removing these gums, which function as natural emulsifiers and are responsible for increasing the oil’s viscosity. 

As a result, high viscosity is an obstruction in carrying out other filtration steps. To fix the physical issues, degumming forms the first step. However, degumming is an optional measure as it mostly depends on gums’ concentrations and lecithin’s value. 

Based on this, there are a variety of degumming processes, including dry, total, soft, enzymatic, and membrane degumming. 

Alkali Refining 

After concluding the degumming process for edible oil, alkali refining treats edible oils and fats with an alkali solution. This traditional process, prevailing for centuries, converts FFA (free fatty acids) into soaps with water solubility. Hydration helps proteins, carbohydrates, and phospholipids to convert into water-soluble contents. After the treatment, water washes away any soap residuals in the area unit for oils and fats. 

Bleaching

Following the degumming and alkali refining treatment, the obtained oil still has remnants of iron, soap, carotenes, and phospholipids. Therefore, the crucial process of bleaching of edible oil materializes to eradicate these undesirable substances. The bleacher with agitation and steam has a primary bleaching vessel, acidic treatment, hermetic filters, and an individual compounding device for earth and oil. The separate arrangement keeps the bleaching earth from transferring into the vacuum system. 

Dewaxing/ Winterization 

The final product, which comprises phospholipids, waxes, and tocopherols, can result in turbidity issues. Therefore, refining the oil further will separate these contents from the oil through dewaxing or winterization. This process may take place before or after the bleaching of edible oil. 

The general process involves reducing the heat of the oil at room temperature by stirring blandly for the crystallization of substances with higher points. The refineries then use popular techniques like filtration, decantation, or centrifugation to separate the solids. However, less challenging alternatives are also present to filter the impurities. 

Deodorization 

Deodorization follows up with dewaxing to eliminate any unpleasant or unacceptable flavors and smells from the oil. This measure will work on expelling unsaponifiable contents like sterols or fatty acids.  

Physical Refining 

The physical refining process comprises removing FFA (free fatty acid) with steam distillation. The technique involves high vacuum and warm temperatures. 

Conclusion 

 

Raw vegetable oil undergoes multiple essential treatments to produce edible oil. The unrefined vegetable oil comprises FFAs, waxes, heavy metals, aldehydes, peroxides, and other substances that affect the final product’s appearance, odor, and flavor. Therefore, it requires treatment to make it healthier. If you happen to be looking for edible oil plant manufacturers for installation, Mectech is a leading vegetable oil refinery manufacturer and supplier in India and globally.

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