News & Technicals

How to Improve Oil Yield of Peanut Oil Press

Peanut oil press are divided into hot pressing method and cold pressing method.
Refined peanut oil is made by hot pressing of roasted peanut, roasting peanut before pressing it will make the oil taste more fragrant, but the oil appearance is slightly black. Roasting is a kind of wet heat treatment for peanuts, which can make the peanuts have a certain elasticity to facilitate the pressing. The purpose of steaming and roasting is completely destroys the cell structure of peanut; denatures the protein, thus reducing the adsorption of oil; improving the quality of oil, reducing the content of colloids and other low-molecular substances.

factors affect the oil yield of peanuts

First of all, fresh peanuts contains relatively high moisture content which will affect the oil output rate, and the slag that is squeezed out will be thicker and more humid. We have tested with the same peanut oil press, dried peanuts oil yield is 5~7% higher than fresh peanut.
Therefore, peanuts of different seasons, peanuts of different origins, and peanuts of different categories will affect the oil yield too.

How to Improve Oil Yield?

1. Oils in different harvesting seasons will affect the oil yield, pick the peanuts in proper time to make sure high quality of raw groudnut.
2. Different areas will also affect the oil yield. For example, peanuts from Shandong have higher oil yields, while peanuts from Guangdong have lower oil yields. 
3. Different types will also affect oil yield. Peanut with red skin has low oil yield compared with white peanut, some peanuts are only suitable for eating and not suitable for oil extraction;
4. Storage methods will also affect oil yield; peanut should be storaged in clean and dry place.
5. When roasting peanuts, a peanut roasting machine will also improve the oil yield.