Making soya bean meal involves processing soybeans, typically through methods that prepare them for various uses, often involving heat to improve nutritional value and remove harmful compounds. A common method described in one process involves a mechanical approach.
Soya bean meal is a widely used ingredient, particularly in animal feed due to its high protein content. Producing it requires processing raw soybeans to make their nutrients more available and eliminate natural inhibitors.
The Mechanical Soya Bean Meal Process
Based on a mechanical process, preparing soya bean meal follows several distinct steps. This method utilizes machinery to crush and press the beans.
Here is a breakdown of the typical mechanical process:
- Cracking the Soybeans: First, the raw soybeans are cracked. This breaks open the beans, separating the hull from the inner kernel (cotyledon).
- Drying the Beans: The cracked beans are then dried. This step reduces the moisture content, which is important for subsequent processing and storage.
- Heating (Steaming): The dried beans are heated, often by steaming. This crucial step prepares the beans for pressing and, importantly, helps to neutralize undesirable substances present in raw soybeans.
- Mechanical Pressing: The heated beans are then fed into a mechanical press, specifically a screw press. This machine applies pressure to extract oil from the beans. The friction generated by the screw press further contributes to heating the material.
- Drying Flakes: The material that remains after pressing is in the form of flakes or a cake. These resulting flakes are dried.
- Grinding the Flakes: Finally, the dried flakes are ground into a meal. This grinding process yields the fine or coarse texture characteristic of soya bean meal.
Why Heating is Important
As highlighted in the mechanical process, heating the soybeans (via steaming and the friction from the screw press) is essential because it destroys the anti-nutritional factors in raw soybeans. These factors, such as trypsin inhibitors, can interfere with nutrient digestion and absorption in animals. Heating denatures these compounds, making the meal safe and nutritious.
While this outlines a common mechanical method, other processes like solvent extraction are also used industrially, often yielding a meal with lower residual oil content. However, the core principles of preparing the beans and applying heat remain fundamental to producing quality soya bean meal.
