棕榈仁饼和榨油机的区别：2025 年终极指南（5 个关键事实）

Introduction: Demystifying Palm Kernel Byproducts

Understanding the primary difference between palm kernel cake and expeller is crucial for anyone involved in the animal feed or agricultural industries. Both are valuable byproducts of the wider palm oil industry, which also produces 粗棕榈油 (CPO). While the terms are often used interchangeably, they refer to products with distinct characteristics. These byproducts are derived from the kernel of the fruit found in the 油棕果串, but their nutritional profiles and best-use cases can vary significantly.

Palm Kernel Cake (PKC) and Palm Kernel Expeller (PKE) are globally recognized as important ingredients for livestock feed, particularly for ruminants. Their affordability and high-energy content make them a staple in many parts of the world. This guide for 2025 will break down everything you need to know, from extraction methods to nutritional content, helping you make an informed decision for your needs.

棕榈仁饼（PKC）究竟是什么？

Palm Kernel Cake, commonly known as PKC, is the solid material that remains after the oil has been extracted from the 棕榈仁. It is essentially the ground-up, de-oiled version of the kernel. This resulting “cake” is rich in protein, fiber, and essential minerals, making it a valuable commodity in its own right.

The term “Palm Kernel Cake” is a broad label that can encompass products made from different extraction techniques. However, in technical discussions, it is often used to refer to the product of solvent extraction, which results in a lower residual fat content. The key to understanding the difference between palm kernel cake and expeller lies in how this oil is removed.

Understanding Palm Kernel Expeller (PKE)

Palm Kernel Expeller (PKE) is a more specific term. It refers exclusively to the cake produced through a mechanical extraction process known as an expeller press. This high-quality byproduct, often referred to simply as 棕榈仁压榨机, is made by crushing and physically pressing the kernels to squeeze out the oil. No chemicals are used in this process.

Because the expeller method is purely mechanical, it is less efficient at oil removal than chemical methods. Consequently, PKE typically has a higher residual oil (fat) content compared to solvent-extracted PKC. This higher fat content means PKE is also higher in energy, a trait that can be highly desirable for certain types of livestock feed formulations.

The Core Difference Between Palm Kernel Cake and Expeller: Processing Method

The most significant difference between palm kernel cake and expeller is the oil extraction method. This single factor influences the final product’s nutritional composition. The process separates the valuable 棕榈仁油 from the solid meal. Even the hard outer casing, the 棕榈仁壳, is used as a high-grade biofuel, showcasing how every part of the palm fruit is utilized.

Mechanical Extraction (Expeller Press)

This process creates what is known as Palm Kernel Expeller (PKE). The kernels are cooked and then forced through a screw press (the expeller) that uses immense pressure to separate the oil from the solid matter. This method is often favored for its simplicity and for avoiding the use of chemical solvents.

• End Product: 棕榈仁压榨机（PKE）
• Residual Oil Content: Higher (typically 6-12%)
• 优点： Chemical-free process, higher energy content in the final product.
• 缺点： Less oil is extracted from the kernels, lower protein concentration by percentage.

For more detail on mechanical extraction, this ScienceDirect article on oil extraction methods provides an excellent scientific overview.

溶剂萃取

This method produces what is more technically referred to as “solvent-extracted palm kernel meal,” but often just called Palm Kernel Cake (PKC). After an initial pressing, a solvent (usually hexane) is used to wash the cake and dissolve the remaining oil. The solvent is then evaporated and recovered for reuse, leaving behind the de-oiled cake.

• End Product: Solvent-Extracted Palm Kernel Cake (PKC)
• Residual Oil Content: Very Low (typically 0.5-3%)
• 优点： Highly efficient oil extraction, higher concentration of protein in the final product.
• 缺点： Involves chemical use, lower energy (fat) content in the cake.

Nutritional Showdown: A Comparative Look

The variation in processing directly impacts the nutritional value. The primary difference between palm kernel cake and expeller from a nutritional standpoint is the fat-to-protein ratio. PKE, with its higher fat content, provides more metabolizable energy.

As noted by the 联合国粮食及农业组织（粮农组织）, these components make PKC a medium-grade protein feed, suitable for complementing other feedstuffs.

Key Applications in Animal Feed

Both PKE and PKC are predominantly used in animal feed, but their unique properties make them suitable for different animals. For those formulating feed, understanding the difference between palm kernel cake and expeller is key to optimizing animal health and growth.

For ruminants like cattle, sheep, and goats, the high fiber content is easily digestible and beneficial. The higher energy in PKE can be particularly useful for dairy cattle or for fattening livestock. In contrast, poultry and swine (monogastric animals) have difficulty digesting the high levels of crude fiber, which can limit its inclusion in their diets. However, research is ongoing to improve its digestibility through processes like fermentation, as detailed in journals like Fermentation.

Conclusion: Which One is Right for Your Needs?

总之，关键在于 difference between palm kernel cake and expeller boils down to the production method, which dictates the residual fat content and, therefore, the energy value of the feed.

Palm Kernel Expeller (PKE) is the product of mechanical pressing, resulting in a higher-fat, higher-energy feed. Palm Kernel Cake (PKC), in its strictest sense, often refers to the product of solvent extraction, yielding a lower-fat, higher-protein concentration meal. While the industry often uses the terms without distinction, knowing this difference is vital for precise feed formulation and achieving specific nutritional goals. The sustainability of palm products is also a major consideration, with organizations like the 可持续棕榈油圆桌会议（RSPO） working to certify sustainable practices.

Ultimately, whether you choose PKC or PKE will depend on your specific needs, the type of livestock you are feeding, and your desired nutritional outcomes. This 2025 guide equips you with the foundational knowledge to distinguish between these valuable agricultural commodities confidently.