Soaking is a step takenĀ before cooking beans and grains, an important part ofĀ sprouting nuts, seeds, beans and grains, and aĀ practice that's encouraged for thoseĀ consumingĀ nuts and seeds in their raw form.Ā 

There are countlessĀ different ways to soak nuts, seeds, beans or grains. The basic steps of soaking include:Ā 1) placing the food, such as beans, in a large bowl or jar,Ā 2) generously covering them with water and 3) leaving them to soak for several hours. There are many benefits to soakingĀ which we'll explore in more detail below.Ā 

The benefits of soaking

  1. Reduces phytic acids and improves the absorption of important nutrients and minerals, such as protein, iron, zinc and calcium.Ā 
  2. Reduces tannins and polyphenols.
  3. Reduces anti-nutritional enzyme inhibitors.
  4. Removes gas-causing compounds.Ā 
  5. Improves texture and decreases cooking time.Ā 

1.Ā Reduces phytic acids

Phytic acid, also known as phytate,Ā is a compound commonly found in cereals and grains. Phytic acid is sometimes called an anti-nutrient because it binds to certain proteins and minerals such as iron, zinc, and calcium. By binding to these nutrients, itĀ reducesĀ their ability to be absorbedĀ in ourĀ body. Processes that remove or degrade phytic acidĀ have been shown to improve the absorption of proteins and some minerals (1,Ā 2,Ā 3,Ā 4,Ā 5).

Enzymes areĀ special proteins in ourĀ body that speed up reactions, such as digestion. Soaking decreases the phytic acidĀ content of foods in two ways: 1) soakingĀ increases the activity of enzymesĀ called phytasesĀ which helpĀ breakdown phytic acid, and 2) when soaked, phytic acid molecules leach into the soaking water that's drained and discarded. Overall,Ā the amount of phytic acid decreases as soaking time increases. Ā Ā 

2.Ā Reduces tannins and polyphenols

Polyphenols are micronutrients found in a variety of fruits, vegetables, grains, beans, nuts, and some beverages. Tannins are a subclass of polyphenols.

You may have heard of theseĀ compounds being in coffee, tea, red wine, and darkĀ chocolate. Polyphenols and tannins are what give these foods their bitter and astringentĀ traits.Ā 

Polyphenols have beenĀ recognizedĀ as the most abundant source of antioxidants in our diet. However, they alsoĀ bind to positively charged minerals (such as iron) and proteins, making them unavailable for absorption inĀ our bodies. Reducing levels of tannins and polyphenols through soaking helps increase ourĀ body's ability to absorb minerals includingĀ iron, zinc, and calcium, as well as proteins found in foods such asĀ chickpeas, mung beans, lentils, and peas.

Similar to phytates, soaking serves to reduce polyphenol and tannin concentrations in two ways: 1) soaking activates the enzyme polyphenol oxidase, resulting in the breakdown and lossĀ of polyphenols, and 2) lossesĀ may result from these compounds leaching into the soaking medium fromĀ the seedĀ coatĀ because they're able to dissolve in water. Significant reductions in the levels of polyphenolsĀ and tannins areĀ observedĀ during the first 2 ā€“ 4Ā hours of soaking in water.

3.Ā Reduces anti-nutritional enzyme inhibitors

Leguminous crops such as beans, peas, and lentils contain several anti-nutritional factors. These anti-nutrientĀ factorsĀ bind to beneficial enzymes which decreasesĀ their activity. We can improveĀ the availability of nutrients present in these foods by removingĀ theirĀ anti-nutrient factors (which include trypsin and chymotrypsin inhibitors, proteolytic enzyme inhibitors, oligosaccharides, and lectins).Ā Several studiesĀ have recognized the importance of soaking to help discard anti-nutrient compounds in the soaking water.

cashews soaking in a bowl of water because of the benefits of soaking nuts and seeds for health
It's usually best to soak beans, nuts, seeds, and grains for several hours, but if we're tight on time, soaking for a few minutes is better than not soaking at all!

4. RemovesĀ gas-causing compoundsĀ 

Eating large quantities of beans is known to cause flatulence, or gas, bloating,Ā and fartingĀ in humans. We can thank what are called oligosaccharides for this. As humans, we can't break down oligosaccharides because we don't have the protein needed to digestĀ themĀ in our small intestine. As a result, naturally occurring bacteria in ourĀ large intestineĀ uses these undigested oligosaccharides. ThisĀ producesĀ gasesĀ and can causeĀ abdominal rumbling, diarrhea and general discomfort in some people. Soaking beans beforeĀ cooking them has long beenĀ shownĀ to reduce the degree of flatulence experienced.

When soaking beans,Ā discarding and re-filling the soaking waterĀ several timesĀ during the soaking period helps to remove more of these gas-forming compounds than one single soak. Ā 

5. Improves texture and decreases cooking timeĀ 

In addition to the removal of flatulence-causing compounds, the soaking of beans before cooking is aĀ common practiceĀ to soften the texture and quicken the cooking process. Soaking for several hoursĀ increases the water in the seeds which speeds upĀ chemical reactions, such as starch gelatinization, during cooking.

Summary

  1. The health benefits of consuming nuts, seeds, beans and grains are many. By simply soaking these foods before preparing or eating them, the anti-nutritional properties can be significantly reduced. Lots ofĀ literature has demonstrated the varied benefits of soaking,Ā including increased nutrient availability and overall digestibility, as well as quicker cooking times.
  2. Soaking between 2 - 8 hours is recommended, but even a few minutes is better than nothing at all.
  3. Drain and refillĀ the water when soaking uncooked beans and lentils.Ā Discarding the soaking water and re-fillingĀ with fresh water one or two times during the soaking period helps to decreaseĀ the gas and bloating that may result from eating these foods.Ā