What are the steps in peanut oil refining?

Peanut oil production is a complex process that involves multiple stages and equipment. From raw material preprocessing to oil refining, each step requires specialized machinery and technology to ensure the quality and safety of the peanut oil. The equipment required for peanut oil production in an oil plant includes raw material preprocessing, which is the first step involving cleaning, crushing, and steaming peanuts. Therefore, the oil plant needs peanut cleaning machines, crushers, and steaming pots. Next is the pressing stage, where screw oil presses or hydraulic oil presses are used to effectively extract oil from peanuts. The pressed peanut cake also requires further processing, such as drying and grinding, for subsequent use. Additionally, the oil plant must be equipped with oil storage tanks, oil pipelines, and measuring instruments to ensure accurate storage, transportation, and measurement of the oil.

The refining process of peanut oil involves several key steps to remove impurities, odors, and pigments, ultimately improving the quality and taste of the oil. 

Peanut oil refining steps:

Degumming 

This step removes phospholipids and other colloidal substances from peanut oil. By heating the oil and adding chemical reagents, these substances aggregate into larger particles, which are then separated through centrifugation or filtration.

Neutralization (Deacidification)

The goal is to reduce the free fatty acid content in the oil, usually done by alkali refining or distillation. Alkali refining involves adding an alkaline solution to neutralize free fatty acids, forming soapstock and glycerol, which are then removed through separation methods. Distillation utilizes the volatility of fatty acids under high temperatures and vacuum conditions to remove them.

Bleaching (Decolorization) 

This step removes pigments from the oil, making it clearer. It is commonly achieved using adsorption bleaching, where activated carbon or other adsorbents absorb pigments and impurities. After a period of contact, the adsorbents are removed through filtration.

Deodorization 

This process eliminates undesirable odors and volatile substances from the oil, enhancing its taste and stability. It is typically conducted using high-temperature vacuum distillation, where odor compounds evaporate and are collected through condensation.

Cooling and Packaging

The refined peanut oil is cooled and packaged using automated equipment for storage and sale.

Each refining step plays a crucial role in ensuring the peanut oil meets food-grade standards. By continuously improving technology and upgrading equipment, manufacturers can enhance quality and production efficiency to meet market demands and drive industry growth.