What to Eat - Part 2 - Legumes

Continuing with “What to Eat” as a part of a healthy diet, we look at legumes. Beans, peas, lentils, and peanuts are a source of high quality nourishment, and have often been called the poor man's meat. When served with whole grains and a small amount of animal protein with good quality animal fat, we are talking about an ideal, low-cost diet.

Legumes contain protein, fiber, with boatloads of minerals, such as magnesium, potassium, phosphorus, iron and molybdenum, as well as B vitamins such as folate and thiamine. Legumes also contain both omega-3 and omega-6 fatty acids, with kidney and pinto beans particularly high in omega-3. They are particularly good for the heart given the soluable and insoluable fiber that helps keep artery clogging cholesterol in check, and the magnesium and potassium that are frequently lacking in the American diet yet are vital for the normal functioning of the heart and circulatory system. These minerals help to regulate blood pressure as well as electrical impulses of nerves and muscle (including heart) contraction. Legumes, particularly lentils, contain high amounts of B vitamins which convert homocysteine in the bloodstream to a form that is not harmful. Homocysteine which is a byproduct of protein metabolism can damage arterial walls and is a very predictive marker of heart disease.

So why do we hear that legumes are bad? Well, if you go back to our article on grains, some of the same caveats apply. Like grains, legumes contain anti-nutrients such as phytates and trypsin inhibitors, and some have specialized complex sugars that can wreak havoc on our gut without proper preparation. Phytic acid also prevents the proper absorption of some minerals, especially iron and zinc. The good news is that we clever humans devised ways to prepare legumes so they are safe, savory and nutritious.

How to Prepare Legumes

Softer legumes, such as lentils and peas, are easily prepared by soaking for several hours before cooking gently until soft. The soaking helps break down the phytic acid, and gentle cooking makes the protein digestible, especially if served with digestion-enhancing spices, pickles, chutneys or fermented dairy products such as yogurt or sour cream. Indian spices are particularly helpful to enhance digestion.

The harder beans, such as kidney beans, black beans or navy beans, require more careful treatment. They contain large, complex sugars called oligosaccharides which ferment in the intestines causing the all too familiar side-effect, gas. We do not produce the enzyme that is necessary to break down these sugars. So how do we break these sugars down so that we can digest them and not smell up the neighborhood?

First of all, choose your beans with great care. Beans that are more than 13 months old after harvest have low, poor quality nutrients and are harder to rehydrate, which means they are more difficult to cook completely, and will be largely indigestible. The best age for “fresh” dried beans is from harvest to four months old. How do you tell how old they are? Look for lighter colored beans, no matter what type. Older beans will be darker in color. Also, younger beans will have fewer cracked skins and less splitting overall. Fava beans contain contain a substance that can cause life threatening anemia for some with an inherited susceptibility, so we don't recommend them. Soybeans should only be eaten fermented in products like miso, tempeh and natto. Store beans at home in glass or earthenware jars in a dry, cool place; when dried beans either absorb moisture or dry out excessively, nutrition and cooking qualities will suffer.

The key to the “flatulence-free” method of bean preparation is to utilize this two step process. Step one leaches out the complex sugars, and step two activates the enzymes to pre-digest the sugars in the legumes so that we have an easier time digesting them.

Step 1

This step rehdrates the beans so that the enzymes can get into the tissues and digest the sugars. It can take ten to twenty-four hours. See the chart for soaking times and optimal pH of the water for soaking.

In Step 1, beans are covered with four times their weight in water which has been warmed to about 113°F. The water used in this stage should be soft; just slightly acid to alkaline with a pH of 6.5 to 9.0. Hard water, which is high in calcium, will hinder the rehydrating and leaching effects of the warm water on beans. Our municipal water in this area is usually around 7.0, but if you have well water, it may be hard and have a lower pH, and you may want to add a pinch of baking soda during this process to alkalinize the water. You don’t need to worry about having the optimal pH if your diet contains animal foods and if the soaking is followed by a long slow cooking (see Step 2). You may add a 4-to-6-inch strip of the sea vegetable kombu (a member of the kelp family) to the bean pot during this period. Kombu helps alkalinize the water, and also contains the enzyme needed for digesting these complex sugars. It also lends a meaty flavor to the beans (not at all fishy) and is mineral-rich, with additional B vitamins and trace elements, as well as a digestion-soothing gel that literally melts into the bean sauce.

Neutralizing Phytic Acid – Soaking times and water pH (from Weston A. Price website)

Step 2

After soaking, drain the beans and rinse well, then add to a pot with more water and bring to a simmer. If digestibility is a problem for you, kombu added to the pot should take care of any pesky complex, gas causing sugars that may not have been leached out. Cook the beans gently until completely tender.

That's it – not difficult, just takes some planning ahead.

What about canned beans? 

Canned beans are processed at high temperatures and pressures that do reduce phytate content, but they tend to destroy the proteins and other nutrients. Use them sparingly.

Fun fact: Early Egyptians built and dedicated temples to the life-supporting attributes of legumes, and later the ancient Greeks and Romans favored beans and lentils in their pantheistic festivals. In fact, four of the most prestigious families of Rome were named for highly valued legumes: Fabius (fava beans), Lentulus (lentils), Piso (peas) and Cicero (chickpeas).   

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