What is Phytic Acid and Why Reduce It?
Phytic acid, or phytate, is a compound found naturally in many plant-based foods, including nuts, seeds, grains, and legumes. It serves as the main storage form of phosphorus in these plants. While phytic acid has some beneficial antioxidant properties, it is also considered an "antinutrient" because of its ability to bind to important minerals.
When ingested, phytic acid can chelate—or bind to—minerals like iron, zinc, calcium, and magnesium in the digestive tract. This creates an insoluble complex, preventing the body from properly absorbing these essential nutrients. For individuals whose diets are heavily reliant on high-phytate foods, this can potentially lead to mineral deficiencies over time. Furthermore, phytic acid can inhibit certain digestive enzymes, such as pepsin and amylase, which can cause digestive discomfort. Reducing phytic acid levels is a preparation strategy employed to minimize these effects, thereby potentially improving nutrient bioavailability and digestion.
Scientific Evidence on Soaking Almonds
Numerous studies have investigated the effect of soaking on phytic acid levels in nuts, including almonds. A study published in the International Journal of Food Science & Technology analyzed the impact of various soaking methods on several nuts. For whole almonds, the study found that soaking in either plain water or a salt solution for 12 hours resulted in only a small, non-significant reduction in phytate concentration compared to unsoaked nuts. However, when chopped almonds were soaked, there was a statistically significant—though still modest—decrease in phytate levels. Other research also suggests that soaking can reduce antinutrients in grains and legumes more effectively than in nuts.
While the reduction in phytic acid from soaking alone may be minor, it is not the only benefit. Soaking starts the germination process, activating beneficial enzymes that aid in breaking down antinutrients. The softened texture also makes almonds easier to chew, which in turn helps release nutrients for better absorption during digestion. Adding a small amount of salt to the soaking water is also believed by some traditional food preparers to help activate these enzymes.
Optimal Soaking Time and Method for Almonds
For most home cooks and health enthusiasts, the recommended soaking time for almonds is an overnight soak, typically lasting between 8 and 12 hours. This duration is long enough to initiate the germination process and soften the nuts without risking spoilage.
Here is a step-by-step guide to soaking almonds effectively:
- Step 1: Choose Your Almonds. Start with raw, unsalted almonds. Organic is often preferred to avoid chemical residues.
- Step 2: Rinse Thoroughly. Place the almonds in a colander and rinse them under cool running water to remove any dirt or impurities.
- Step 3: Prepare the Soaking Solution. Put the almonds in a large glass bowl. Cover them completely with warm, filtered water. Add a pinch of sea salt—approximately one teaspoon per cup of almonds—to help facilitate the enzyme activation.
- Step 4: Soak Overnight. Cover the bowl with a clean cloth or a breathable lid. Let the almonds soak on the countertop or in the refrigerator for 8 to 12 hours.
- Step 5: Drain and Rinse. In the morning, drain the murky soaking water and rinse the almonds thoroughly under fresh running water.
- Step 6: Dry or Use Immediately. You can eat the soft, soaked almonds right away. If you prefer a crunchy texture or plan to store them for an extended period, you must dry them. Use a dehydrator at a low temperature (below 150°F / 66°C) or an oven on its lowest setting for 12 to 24 hours until completely dry and crispy.
Other Methods to Reduce Phytic Acid
While soaking is the most common home method, several other techniques can help reduce phytic acid content in plant foods:
- Sprouting: After soaking, draining, and rinsing, place the damp almonds in a container with good air circulation. Rinse them every 8 hours until small sprouts appear, typically over several days. Sprouting activates enzymes more effectively than soaking alone.
- Roasting: High-heat roasting can also break down phytic acid. However, this process can potentially damage other beneficial nutrients and fats in the almonds. Low-temperature dehydration is often a better option for preserving nutrient integrity after soaking.
- Fermentation: Fermentation is a highly effective method for reducing phytic acid, particularly in grains and legumes. While less common for nuts, some products like tempeh utilize fermentation to break down phytates.
- Using Phytase: Commercial microbial phytase enzymes are added to animal feed to improve mineral absorption. While not a common home method, it is an industrial solution for reducing phytate content.
Soaking Time Comparison for Different Nuts
| Nut Type | Recommended Soaking Time | Why Different Times? |
|---|---|---|
| Almonds | 8–12 hours (overnight) | Hard texture requires a longer soak to soften and activate enzymes. |
| Walnuts & Pecans | 4–6 hours | These are oilier and softer, so they require a shorter soak to avoid becoming mushy or slimy. |
| Cashews | 2–4 hours | High fat content and soft texture mean a short soak is sufficient; longer times can cause spoilage. |
| Macadamias | 2–4 hours | Another high-fat, softer nut that only needs a short soak. |
| Hazelnuts | 8–12 hours (overnight) | Similar to almonds in firmness, they benefit from a longer soaking period. |
Conclusion: Maximizing Benefits with Proper Soaking
While soaking almonds for 8 to 12 hours offers a modest reduction in phytic acid, the benefits extend beyond this single factor. The process helps activate enzymes, soften the nuts for easier digestion, and can improve the bioavailability of minerals like iron and zinc. By following the proper soaking and optional drying procedure, you can enjoy a more digestible and nutritious snack. For those with sensitive stomachs or a diet high in plant foods, this simple preparation step can make a noticeable difference. Ultimately, incorporating a varied diet is the best strategy, but preparing your nuts thoughtfully is a simple way to boost their nutritional value and your body's ability to absorb it. Further research continues to explore the optimal processing methods for plant-based foods to enhance mineral absorption.
Considerations for Soaked Almonds
- Texture Change: Soaked almonds lose their original crispness and become softer. If you prefer the crunch, you must thoroughly dehydrate them after soaking. Failure to completely dry them will result in a chewy, not crispy, texture.
- Storage: Soaked and undried almonds should be stored in an airtight container in the refrigerator and consumed within 2-3 days. For longer storage, dehydrate them fully before placing them in an airtight container in a cool, dark pantry or freezer.
- Peeling: The brown skin on almonds contains tannins, which can contribute to a slightly bitter flavor. Once soaked, the skins become easy to peel off. Removing them results in a milder, sweeter flavor and a smoother texture.
- Warmth vs. Refrigeration: Soaking at room temperature can accelerate enzyme activity. For longer soaks or in warmer climates, soaking in the refrigerator is a safer option to prevent spoilage.
- Water Quality: Using filtered water is recommended, as tap water may contain minerals that could interact with the soaking process or chemical additives.
