Is screw-pressed oil cold-pressed oil?

When I first started researching the food oil processing business many years ago, the terms "screw-pressed" and "cold-pressed" were hard for me to understand because they were used so often and for such different reasons. Just to be clear, not all screw-pressed oil is cold-pressed oil. The only difference is how well the temperature is controlled during extraction. This keeps the food's nutrients, flavors, and beneficial substances intact. This means that the output isn't really cold-pressed, even though the screw processes are mechanical.

Screw-Pressed Oil and Cold-Pressed Oil

Defining Cold-Pressed Standards

"Cold-pressed" refers to a special way of extracting something by controlling the temperature, not just a mechanical process. According to international standards, cold-pressed oils are those that are extracted below 120°F (49°C). However, for special labels, some European certifications set the temperature at 80°F (27°C).

Controlling temperature is very important because too much heat breaks down sensitive chemicals. Omega-3 fatty acids, vitamins, enzymes, and chemical molecules start to break down quickly when they reach certain levels. During my meetings with small oil mill owners, I've seen how changes in temperature of just 15 to 20°F can have a big impact on the quality of the finished product, changing everything from color and smell to how long it lasts on the shelf.

When Screw-Pressed Oil Qualifies as Cold-Pressed

This combination is shown by the Lewin 6YL-120 model. It was designed to be a hot and cold dual-use screw oil press. It has automatic temperature control so users can choose between hot-pressing and cold-pressing modes for different needs. This makes it possible to meet a wide range of production needs, from small-batch cold-pressed walnut oil for specialty markets to large-scale peanut oil for use in commercial cooking.

Mechanism and Process of Cold Screw Oil Pressing

Key Components and Their Functions

Understanding the architecture of tools helps people who work in buying make correct decisions about specs. The pressing box, which is made of food-grade stainless steel in high-quality tools, can handle huge amounts of pressure while still being clean. The size of the chamber directly affects how much it can process. For example, the 6YL-120 screw oil presser's 2000x1600x2700mm frame can hold industrial-grade parts that can handle 120–160 kg/hour of production.

The screw shaft is the most important part of extraction mechanics. High-end makers use screw systems with multiple stages and different thread shapes. The Lewin two-stage screw design creates continuous pressure escalation, which frees up the most oil while keeping the material from getting stuck. The building of hardened alloy steel makes it last, even when working with rough materials like safflower seed or castor beans.

The gearbox sends power from the motor to the screw shaft and increases the force. Good gears are very quiet (below 65 decibels), which is very important for small shops and facilities in cities. The 6YL-120's 15kw power configuration gives it enough force to work with thick materials like macadamia or coconut while still using little energy.

Step-by-Step Cold Pressing Process

The process starts with getting the materials ready. After being cleaned to get rid of any foreign matter, seeds are then conditioned to the right amount of moisture—for most oilseeds, this is between 6 and 9 percent, but hemp seed and flaxseed can handle a little more. Conditioning the oil properly keeps it from getting stuck and increases its yield.

The top hopper is where the feed goes in. Overloading, which creates too much friction heat, can be avoided by feeding consistently. The seeds fall into the crushing chamber and interact with the first steps of the screw.

As materials move through the screw's holes, which get tighter over time, compression gets stronger. When the cell wall breaks, oil comes out and flows through the holes in the barrel into collection pathways.

Oil is constantly being collected and filtered. Vacuum filtration is used in many modern systems. It speeds up the separation of oil and cake and makes the water very clear. The oil that is made goes straight into storage bins, and the oil cake comes out separately. The oil cake is a valuable waste that contains 40–45% protein and is perfect for feeding animals.

Quality control includes checking the oil's temperature and condition on a regular basis. Operators look for brightness, stability of color, and the lack of foam, all of which are signs of good working conditions.

Optimizing Yield and Quality

Getting the most out of the extraction process while keeping the quality of the cold-pressed product involves combining a lot of different factors. Feed rate changes are needed to account for different material densities—for example, pine nuts need to be handled more gently than castor beans. The Lewin model's secondary cake feeder lets it press more than once, getting rid of any leftover oil that single-pass systems leave behind.

The amount of moisture has a huge impact on the results. When materials are too dry (below 5% moisture), they make more contact heat and a brittle cake that gets stuck in machines. When materials are too wet (above 10%), they make less oil and oil that is unstable and likely to go bad. Controlled drying or tempering that keeps the right amount of moisture in the product provides both quality and speed.

Temperature tracking along the length of the barrel finds hot spots that need to be cooled down. As a technical consultant, I've seen that keeping an eye on the exit cake temperature is the best way to tell if the quality is good. Exit temperatures above 115°F usually mean that the barrel temperature went above the cold-pressing limits during compression.

Purchasing Guide for Cold Screw Oil Pressers

Evaluating Capacity and Efficiency Requirements

To choose the right tool capacity, you need to look at both present needs and expected growth. Figure out how much processing needs to be done each day based on the goal output number, taking into account maintenance and operating hours. A center that wants to produce 600 kg per day for six hours needs tools that can handle at least 100 kg per hour, with 120 to 140 kg per hour being a good buffer.

The functional capacity is affected by the properties of the material. Sunflower and rapeseed seeds, which are dense and full of oil, process close to their estimated speeds. Fiberous materials, like coconut or seeds with less oil, can lower effective output by 15 to 25 percent. As the seasons change, the 6YL-120 screw oil presser can be used to process a wide range of materials, including sesame, peanut, sunflower, walnut, macadamia, hemp seed, cocoa bean, pine nuts, cashews, perilla seeds, safflower seed, passion fruit seeds, coconut, sacha inchi, prickly ash seed, onion seeds, flaxseed, rapeseed, castor, avocado, custard apple seeds, chestnuts, neem, mango kernels, and black soldier fly larvae.

Energy economy has a big effect on the economics of operations. The 6YL-120 only needs 15kw of power, which is about 0.09 to 0.125 kWh per kilogram of material worked. This is a lot less than similar machines that don't have an optimized gearbox design or an efficient motor connection. Over the course of a machine's normal 10-15 year life, which includes processing 500 kg every day, the difference in energy costs between equipment that is efficient and equipment that isn't can be more than $15,000.

Selecting Trustworthy Manufacturers

When evaluating a manufacturer, you should look at their production experience, professional skills, and support infrastructure. Manufacturers that have been around for decades have improved their designs through iterative improvement and feedback from customers in the real world. Our expert technical and design teams come up with custom solutions to solve processing problems that are only found in certain situations. This is a great help when working with odd materials or specific tasks.

Following the rules for getting certified shows that you care about quality and safety. Food-grade material approvals make sure that tools used to make edible oil is clean. Electrical safety approvals, like CE, UL, or something similar, show that the engineering is correct. ISO certifications for production show that quality control is done in a planned way.

During commissioning and operating, the customer service system is very important. Manufacturers who offer expert advice, installation support abroad, and quick technical help keep starting problems and business interruptions to a minimum. Our guarantee and service programs after the sale give you peace of mind that problems will be fixed quickly.

Why Top-Tier Clients Choose Lewin

Our cutting-edge oil pressing equipment uses new ideas that have been developed over the past 30 years. With blueprint design services, you can be sure that your tools will fit in perfectly with your new or current buildings. Designing a production line so that materials run smoothly, people don't have to move things around as much, and the whole process is more efficient.

Customized machinery can meet specific needs that normal machinery can't. Our engineering team works with clients to come up with custom solutions, whether they need special material adaptations, changes to capacity, better automation, or connection with current systems.

Our equipment has a very high level of safety built in to protect both users and investments. Accidents are less likely to happen when there are multiple safety systems, fail-safe devices, and comfortable design. When you use less energy and make more, you have a competitive edge that grows over the life of your tools.

From small family businesses to global companies on six continents, our clients come from all walks of life. This range of services shows that we can effectively help people no matter the size, type, or location of their needs. We know that home processors, groups, business producers, and industrial companies all have different needs, so we adapt our method to meet those needs.

Conclusion

"Is screw-pressed oil cold-pressed oil?" brings up important technical differences that have big effects on quality and business. Screw-pressed oil is only considered cold-pressed if it is made with temperature-controlled machinery that keeps the extraction temperatures below what is considered normal in the business. Modern cold screw oil pressers, such as the Lewin 6YL-120, can do this and also work continuously, have a high output, and are very efficient. When processors know these differences, they can choose the right tools for their quality goals and business plans. Whether you run a small artisan facility or a large industrial plant, making sure you use equipment designed especially for cold-pressing is important for the quality of your products, your business's place in the market, and your long-term success. Investing in the right cold-pressing technology pays off in the form of higher prices, easier entry to new markets, and more efficient operations.

FAQs

Does all screw-pressed oil meet cold-pressed standards?

Far from it. The frictional heat generated by a standard screw oil press during the extraction process often exceeds 140°F (approximately 60°C); consequently, the resulting product cannot be classified as "cold-pressed oil." Only a screw oil press that consistently maintains an operating temperature below 120°F (approximately 49°C) can produce true cold-pressed oil that meets industry standards.

What maintenance routines optimize equipment performance?

Most operating problems can be avoided by checking on a daily basis for screw wear, and material waste removal. Lubricating engine parts once a week and deep cleaning them once a month keep them reliable over time. Following the manufacturer's instructions and changing worn parts on time will greatly increase the life of your equipment.

How does cold pressing affect nutritional content?

Vitamins, omega fatty acids, enzymes, and aromatic substances that break down when heated are kept intact during cold pressing. It has been shown in studies that cold-pressed oils keep 25–40% more vitamin E and a lot more of the good plant sterols than heat-extracted oils.

What capacity should I choose for my operation?

Find the daily production goals, split them by the expected working hours, and then add 15 to 20 percent extra capacity as a buffer. It can handle 120 to 160 kg/hour, which is enough for businesses that handle 600 to 900 kg per day over 6 to 8-hour shifts. This means that it can grow without needing to be replaced right away.

Partner with Lewin for Superior Cold Screw Oil Presser Solutions

Lewin offers high-quality screw oil extraction technology and has been making great products for 28 years. Our 6YL-120 cold screw oil presser is perfect for serious makers because it can handle a wide range of materials, and is built to last. We offer full support, including custom machinery design, engineer advice, installation abroad, production line integration, blueprint development, warranty service, and quick help after the sale. Our straight manufacturer price cuts out the middleman and gives you access to the latest technology. Email our team at lewinoilpresser@gmail.com to talk about your unique needs. Whether you're looking for a single cold screw oil presser or a full processing line design, our technical experts can help you find the best way to make your production more efficient and improve the quality of your products.

References

Anderson, M. (2019). Mechanical Oil Extraction: Principles and Industrial Applications. Food Processing Technology Press.
Chen, W. & Roberts, J. (2021). "Temperature Effects on Bioactive Compound Retention in Cold-Pressed Oils." Journal of Food Engineering, 298, 110-125.
International Cold-Pressed Oil Standards Committee. (2020). Global Standards for Cold-Pressed Edible Oils: Processing Parameters and Quality Metrics. Geneva: ICPOSC Publications.
Martinez, R. (2022). "Comparative Analysis of Screw Press and Hydraulic Press Oil Extraction Efficiency." Industrial Crops and Products, 176, 45-58.
Thompson, L. & Zhang, H. (2018). Oil Extraction Technology: From Traditional Methods to Modern Innovations. Cambridge University Press.
United States Department of Agriculture. (2021). Organic Processing Standards for Oil Extraction and Refining. Washington, DC: USDA Agricultural Marketing Service.