Rapeseed Oil Processing Comparison: How to Choose Between Hot Pressing, Cold Pressing and Solvent Extraction?

In the global edible oil market, rapeseed oil is highly favored due to its stable flavor, reasonable fatty acid structure, and wide range of applications. For companies preparing to build oil mills or upgrade their processes, the most common question is: should they choose hot pressing, cold pressing, or solvent extraction? Different processes result in vastly different product characteristics, costs, and market positioning, and the correct process route directly determines oil quality, oil yield, and long-term profitability.

This article breaks down the core logic and applicable scenarios of three mainstream rapeseed oil production processes, from pretreatment to refining, and provides a selection guide to help you quickly identify the most suitable route for yourself.

I. Two major technical routes for rapeseed oil production: pressing and solvent extraction

Global rapeseed oil production can be broadly categorized into two processing systems:

1. Pressing method (hot pressing/cold pressing)
   It uses mechanical extrusion as its core and relies on physical methods to extract oil.

2. Solvent extraction (pre-pressing – solvent extraction)
   First, some of the oil is pressed off, and then food-grade solvents are used for further extraction, making it suitable for large-scale production.

Neither of the two processes is inherently superior or inferior; the key factors are the target market, equipment investment, product positioning, and production capacity.

II. Core Work Sections and Key Technologies

Regardless of the specific processing method, the common steps in rapeseed oil processing include:

1. Pretreatment – ​​The fundamental process that determines the pressing effect

The purpose of pretreatment is to make the rapeseed structure easier to extract oil, while reducing subsequent losses caused by impurities.

Key steps include:

• Cleaning and magnetic separation : Removes stones, wood chips and metal impurities, protecting equipment safety.

• Breaking and softening : This process opens up oil cells, making the oil more fluid.

• Conditioning/Cooking (essential for hot pressing) : Enhances oil activity and aroma through heating, humidification, and short-term storage.

Conditioned rapeseed exhibits improved plasticity and flowability, a prerequisite for high oil yield during hot pressing. 👉( Steam Cooker: Improves efficiency and oil yield )

2. Pressing – What are the fundamental differences between hot pressing and cold pressing?

● Hot pressing : Hot pressing is a traditional and well-established method for processing rapeseed oil. The rapeseed, after being steamed and roasted, is heated to a certain temperature and then mechanically pressed to obtain the oil. This method results in a richer aroma and a higher oil yield.

Features:

• The cooking process deactivates enzymes in rapeseed, reducing bitterness.

• According to industry experience, hot pressing yields a higher oil yield than cold pressing (but the actual value depends on the type of raw material, moisture content, and equipment structure).

• Suitable for consumer markets that require rich flavor, such as cooking oils used in Asia and parts of the Middle East.

Advantages:

• It has a distinctive flavor (“hot-aroma rapeseed oil”).

• The oil is darker, but it is more acceptable to consumers.

• Equipment investment is relatively low.

● Cold pressing : Cold pressing uses mechanical pressing at a lower temperature to avoid nutrient loss caused by heating, thus maximizing the retention of natural nutrients such as vitamin E and polyphenols.

Features:

• High-temperature steaming and frying are not carried out, and the pressing temperature is relatively low.

• The oil is light in color and has a more natural flavor.

Advantages:

• It is more suitable to position it as a "high-end healthy oil" or virgin oil.

• It has a mild taste and good storage properties.

Applicable scenarios:

• Markets in Europe, America, and Japan have a high demand for cold-pressed oils.

• Companies that favor small to medium production volumes and emphasize brand value and nutritional selling points.

3. Solvent Extraction – An Efficiency Choice for Large-Scale Plants

The typical route of the solvent extraction method is pre-pressing → solvent extraction (the core of which is to use organic solvents (such as hexane) to extract rapeseed, which can greatly increase the oil yield) → refining.

Advantages:

• Low residual oil content and high raw material utilization rate. The residual oil content in the industry can generally be controlled at a low level (such as below 1%), but the specific value needs to be determined based on the equipment and actual operating conditions.

• More suitable for large-capacity oil plants with a capacity of 100 tons/day or more.

• It has lower energy consumption and lower unit production cost.

Features:

• The process employs a closed solvent circulation system, which meets modern food safety and environmental protection requirements.

• It is suitable for maximizing the value extracted from oil mill by-products (such as rapeseed meal).

4. Refining – determines whether oil products meet market standards.

Whether it's hot pressing, cold pressing, or solvent extraction, virgin oil needs to undergo scientific refining. The purpose of refining is not to "make the oil look pretty," but to make the oil more stable and safer.

The core components include:

• Degumming : Removes phospholipids to prevent precipitation and lowering of the smoke point;

• Deacidification : Reduces acid value and improves oil safety;

• Decolorization : Adsorbs pigments, making the finished oil more transparent;

• Deodorization : Removes odors and improves flavor purity.

This is especially important for export markets, as different countries have specific requirements for acid value, peroxide value, and color.

III. How to choose the most suitable rapeseed oil processing technology according to needs?

Based on actual cases from hundreds of oil mills, we can generally make judgments in the following directions:

1. Want to make a flavorful cooking oil? — Choose hot pressing.

Applicable scenarios:

• Cooking oil, stir-frying oil

• Asian Market

• Brands aiming to create "regional flavors"

Advantages:

• It has a strong aroma and high consumer acceptance.

• Low equipment investment and short payback period

2. Want to produce premium, healthy oils? — Choose cold-pressed.

Applicable scenarios:

• Nutritional oils, premium bottled oils

• High-end retail market

• Product brands that emphasize "natural" and "non-high temperature treatment"

Advantages:

• More refined quality

• Suitable for differentiated marketing in multilingual markets

3. Want high yield at low cost? — Choose solvent extraction.

Applicable scenarios:

• Large factories (100 TPD or more)

• Enterprises that emphasize stable production capacity and low production costs

• Enterprises that need to sell oilseed meals for animal feed

Advantages:

• Low residual oil content and high raw material utilization rate

• Lowest cost per ton of oil

• Industry mainstream large-scale solutions

IV. Why are more and more oil plants choosing QIE Group's overall process solutions?

In the rapeseed oil processing industry, a single piece of equipment cannot solve all the problems; the key lies in matching the complete process chain.
Our advantage lies in:

• It can design parameters based on the characteristics of raw materials (oil content, moisture content, variety);

• We can provide complete plant solutions for hot pressing, cold pressing, pre-pressing – solvent extraction, and refining.

• Supports customized configurations for everything from small factories to large factories;

• The equipment is energy-efficient, highly continuous, and suitable for long-term stable operation.

This allows many customers to no longer simply "buy equipment" when upgrading their factories, but to obtain a comprehensive solution with higher oil yield and lower energy consumption.

FAQ

Q1: Is cold-pressed rapeseed oil really healthier than hot-pressed rapeseed oil?

Cold pressing retains more natural nutrients such as vitamin E and polyphenols, but has a lower oil yield and is relatively more expensive. Hot pressing, while resulting in the loss of some micronutrients due to the high-temperature processing, produces a richer flavor and is suitable for everyday cooking. The two methods are suitable for different groups of people.

Q2: Will there be any safety issues with solvent residue from the leaching method?

Modern solvent extraction processes employ a fully enclosed recovery system, which can effectively recover and control solvents, ensuring that the finished oil meets food safety standards and that solvent residues are far below national standard limits.

Q3: My oil mill is a small to medium-sized enterprise. Which process would you recommend?

Small and medium-sized oil mills can prioritize either hot pressing or cold pressing technologies, choosing the more suitable product style and investment budget based on their market positioning. QIE Group can provide flexible and customized equipment solutions.

Q4: Can cold-pressed oil be sold directly?

Most markets allow the sale of cold-pressed crude oil, but exports or high-end retail typically still require light refining to ensure stability and shelf life.

Q5: What if you want to achieve both fragrance and high oil yield at the same time?

Some oil mills adopt a compromise solution of "hot pressing (pre-pressing) + solvent extraction", which can simultaneously obtain aroma base and higher oil utilization rate.

Q6: Is there a big difference in oil yield between hot pressing and cold pressing?

Hot pressing typically yields higher yields, but the specific difference depends on the type of raw material, moisture content, conditioning temperature, and equipment structure. A fixed value cannot be given; it is best to conduct process experiments based on the actual raw materials.