Know your Beans
Know your Beans - Introduction
Bean is a common name for large plant seeds of several genera of the family Fabaceae used for human food or animal feed.
The whole young pods of bean plants, if picked before the pods ripen and dry, are very tender and may be eaten cooked or raw.
Thus the word "green beans" means "green" in the sense of unripe (many are in fact not green in colour), as the beans inside the pods of green beans are too small to comprise a significant part of the cooked fruit.
Toxicity in beans
Some kinds of raw beans and especially red and kidney beans, contain a harmful toxin (the lectin Phytohaemagglutinin) that must be destroyed by cooking.
A recommended method is to boil the beans for at least ten minutes; undercooked beans may be more toxic than raw beans.
Cooking beans in a slow cooker, because of the lower temperatures often used, may not destroy toxins even though the beans do not smell or taste 'bad' (though this should not be a problem if the food reaches boiling and stays there for some time).
Fermentation is used in some parts of Africa to improve the nutritional value of beans by removing toxins.
Inexpensive fermentation improves the nutritional impact of flour from dry beans and improves digestibility, according to research co-authored by Emire Shimelis, from the Food Engineering Program at Addis Ababa University.
Beans are a major source of dietary protein in Kenya, Malawi, Tanzania, Uganda and Zambia.
The Phaseolus Tribe
There are 50 species of Phaseolus bean and they include haricot, flageolet, and French bean.
Most are perrenial in their American homeland but in England we have to treat them as annuals due to our cold winters.
Common Bean
The common bean, Phaseolus vulgaris, is an herbaceous annual plant domesticated independently in ancient Mesoamerica and the Andes, and now grown worldwide for its edible bean, popular both dry and as a green bean.
The leaf is occasionally used as a leaf vegetable, and the straw is used for fodder.
Botanically, the common bean is classified as a dicotyledon.
Beans, squash and maize constituted the "Three Sisters" that provided the foundation of Native American agriculture.
Beans are a legume and thus acquire their nitrogen through an association with rhizobia, a species of nitrogen-fixing bacteria.
18.3 million tonnes of dry common beans and 6.6 million tonnes of green beans were grown worldwide in 2007.
The other major type of beans is broad beans (Vicia faba), of which only 3.7 million tonnes were grown in 2007.
The commercial production of beans is well-distributed worldwide with countries in Asia, Africa, Europe, Oceania, South and North America all among the top bean growers.
Brazil and India are the largest producers of dry beans while China produces, by far, the largest amount of green beans, almost as much as the rest of the top ten growers altogether.
Many well-known bean varieties belong to the Common bean species, and none of the lists below are in any way exhaustive.
Both bush and running (pole) varieties exist. The colours and shapes of pods and seeds vary tremendously.
Similar to other beans, the common bean is high in starch, protein and dietary fibre and is an excellent source of iron, potassium, selenium, molybdenum, thiamine, vitamin B6, and folic acid.
Know your Beans - Dry beans
Dry beans come from both Old World varieties of broad beans (fava beans) and New World Common Bean varieties (kidney, black, cranberry, pinto, navy/haricot).
Dry beans will keep indefinitely if stored in a cool, dry place, but as time passes, their nutritive value and flavour degrade and cooking times lengthen.
Soaking dry beans
Dried beans are almost always cooked by boiling, often after having been soaked for several hours.
While the soaking is not strictly necessary, it shortens cooking time and results in more evenly textured beans.
In addition, discarding one or more batches of soaking water leaches out hard-to-digest complex sugars that can cause flatulence, though those who eat beans regularly rarely have difficulties with flatulence as intestinal microbes adjust.
There are several methods including overnight soaking, and the power soak method, which is to boil beans for three minutes, then set them aside for 2–4 hours, then drain and discard the water and proceed with cooking.
Cooking dry beans
Dry beans take longer to cook by boiling than most pulses: cooking times vary from one to four hours but are substantially reduced with pressure cooking.
In Mexico, Central America and South America, the traditional spice to use with beans is epazote, which is also said to aid digestion.
In East Asia a type of seaweed, Kombu, is added to beans as they cook for the same purpose.
Salt, sugar, and acidic foods like tomatoes may harden uncooked beans resulting in seasoned beans at the expense of slightly longer cooking times.
Dry beans may also be bought pre-cooked and canned as refried beans, or whole with water, salt, and sometimes sugar.
Know your Beans - Green beans
Green beans are the unripe fruit of any kind of bean, including the yardlong bean, the hyacinth bean, the winged bean, and especially the common bean (Phaseolus vulgaris), whose pods are also usually called string beans in the north-eastern United States, but can also be called snap beans.
There are three commonly known types of green beans:
String or runner beans.
Stringless or French beans (depending on whether the pod has a tough, fibrous "string" running along its length).
Snap beans, with a thin flat pod that requires less cooking time.
Compared to the dry beans, they provide less starch and protein, and more vitamin A and vitamin C.
The green beans are often steamed, boiled, stir-fried, or baked in casseroles.
Green bean varieties have been bred especially for the fleshiness, flavour, or sweetness of their pods. Haricots verts, French for "green beans," may refer to a longer, thinner type of green bean than the typical, American green bean.
Know your Beans - Shell beans
Common beans can be used for shell (or shelling) beans, which have the pods removed before they are cooked or dried.
The term can be used to refer to all species of beans, such as lima beans, soya beans, peas, or broad beans, that have their shell removed before it is eaten.
Nutritionally, shell beans are similar to dry beans, but in the kitchen are treated as a vegetable, often steamed, fried, or made into soups.
Know your Beans - White beans
The small, white haricot bean, also called pea bean or navy bean, is particularly popular in Britain and the US, featured in such dishes as baked beans and even pies, as well as in various soups such as the famous Senate Bean Soup.
Navy bean varieties include:
Great Northern beans
Rainy River
Robust
Michelite
Sanilac
Other white beans include Cannellini, a fairly popular variety in Central and Southern Italy which is related to the kidney bean and like the kidney bean has higher levels of the toxin lectin (Phytohaemagglutinin).
A notable Greek type of giant white beans exists, called yiyantes or gigantes (Greek: γίγαντες). They are produced in a specific part of northern Greece (protected label) but can be found throughout the country.
Know your Beans - Yellow beans
Sinaloa Azufrado, Sulphur, Mayocoba, and Peruano (also called Canary bean) are types of yellow beans.
Peruano beans (also called Canary beans) are small, oval, yellow coloured beans about 1/2 inch (1 cm) long with a thin skin.
Peruano Beans have a creamy texture when cooked, and are one of the top-selling beans in Mexico City since 2005 (being native to Mexico, despite the name).
