Reducing phytic acid in seeds is important for improving nutrient absorption. The most common methods involve processes that break down or remove this compound.
You can reduce phytic acid in seeds primarily through methods like milling or soaking.
Understanding Phytic Acid
Phytic acid, also known as inositol hexaphosphate (IP6), is a naturally occurring compound found in many plant seeds, grains, nuts, legumes, and roots. While it has some antioxidant properties, it is often called an "anti-nutrient" because it can bind to minerals like iron, zinc, calcium, and magnesium in the digestive tract, making them less available for absorption by the body.
Reducing the phytic acid content can significantly enhance the nutritional value of seeds and grains, particularly for individuals who rely heavily on plant-based diets.
Effective Methods to Reduce Phytic Acid
Several techniques can be employed to lower phytic acid levels in seeds. Based on common practices and the provided reference, two key methods stand out for grains and cereals (types of seeds):
- Milling
- Soaking
Let's look at these in more detail.
Milling
Milling is a process where the outer layers of grains are removed. The reference states that milling is the most commonly used method to remove phytic acid from grains.
- How it works: Phytic acid is highly concentrated in the outer layers, such as the bran and germ, of cereal grains. Removing these parts through milling effectively reduces the overall phytic acid content in the remaining flour or grain.
- Advantages: It's a highly effective way to reduce phytic acid.
- Disadvantages: As highlighted in the reference, this technique has major disadvantages because it also removes major parts of essential minerals and dietary fibers that are also concentrated in the outer layers. This means while you reduce phytic acid, you also decrease the overall nutrient density and fiber content of the seed product.
Soaking
Soaking seeds or grains in water is another widely applied and important method for reducing phytic acid. This technique is often a preliminary step in germination and fermentation processes.
- How it works: Seeds contain an enzyme called phytase, which can break down phytic acid. Soaking activates this enzyme, allowing it to hydrolyze phytic acid into less complex forms that do not bind to minerals as effectively. The water also helps leach out some of the phytic acid.
- Advantages: Soaking is simple, inexpensive, and helps activate natural enzymes. It also prepares seeds for further processing like germination or fermentation.
- Tips for Soaking:
- Use warm water, as it can enhance phytase activity.
- Adding a splash of acidic medium like lemon juice or vinegar can sometimes help, especially if the seeds naturally have low phytase activity.
- Soaking duration varies depending on the type of seed and temperature. Overnight soaking (typically 8-12 hours) is common for many grains and legumes.
- Discard the soaking water, as it will contain leached phytic acid and other compounds. Rinse the seeds thoroughly afterward.
| Method | Primary Mechanism | Effectiveness at Reducing Phytic Acid | Impact on Other Nutrients | Common Use Case |
|---|---|---|---|---|
| Milling | Physical removal of outer layers | High | Significantly reduces minerals and fiber | Commercial grain processing |
| Soaking | Activation of natural enzymes (phytase); Leaching | Moderate to High (depends on duration, temperature, seed type) | Generally preserves or improves bioavailability of other nutrients | Home preparation, germination, fermentation |
Other methods like germination (sprouting) and fermentation also significantly reduce phytic acid, often building upon the initial soaking process. Germination activates phytase further, and fermentation involves microorganisms that produce enzymes capable of breaking down phytic acid.
In summary, while milling effectively removes phytic acid by discarding outer layers, it sacrifices valuable nutrients. Soaking is a practical and nutrient-preserving method that utilizes the seed's natural enzymes to break down phytic acid, often serving as a crucial first step for other reduction techniques like germination and fermentation.
