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Legumes
The second most important plant family used in the
human diet, the first being the grasses, and both are thought to have
been first domesticated just over 10,000 years ago.
Beans, though, are on
average, twice as rich in proteins as grains and are especially rich
in iron and B group vitamins. This makes them an ideal source of
protein for vegetarian communities, such as Southern India, where
they form an important part of the diet. Some, like the green
pea and haricot, are eaten green and
in the pod, when they contain more vitamin A and vitamin C, but much
less protein.
In ancient Rome, four of the most prominent families
too the names of legumes: Fabius - faba bean;
Lentulus - lentils; Piso - pea;
Cicero - chick-pea. Beans
are a good source of protein, carbohydrates, minerals and vitamins.
They are a good source of iron, low in fact and an excellent source
of fibre, especially soluble fibre, which may help prevent the
erratic blood sugar levels that lead to cravings for sweet foods.
Fibre also helps to lower blood cholesterol levels, reducing the risk
of heart disease.
All the pulses score well on the Glycaemic Index, the
scale invented to help in the treatment of diabetes, which is used to
measure the rate at which blood sugar levels rise when a particular
carbohydrate bearing food is ingested. Low level GI foods are more
complex and hence digested more slowly, ensuring a longer feeling of
satiety, longer term energy maintenance and keeping blood sugar
levels constant. GI scores below 50 are seen as the best on the
scale, whilst those that score above 70 are regarded as best eaten
with a lower scoring food - and less frequently.
Broad bean - Faba
vulgaris, Vicia faba. Also called the faba
or fava bean, this was the only bean
known in Europe until the discovery of the Americas. Cultivated since
the Man’s earliest times, this humble legume managed to spark a
debate which has spanned 26 centuries. In the 6th century BC Pythagoras,
the Greek Philosopher and mathematician advised his followers, “Abstain
from beans”.
From anyone else these words might have been taken at
face value. But they were spoken, without any further enlightenment
as to why, by a philosopher - a positive invitation to further
speculation. One source says that Aristotle
believed that they were forbidden because they resemble testicles. Cicero,
Plutarch and St. Jerome
all held the theory that it was because they possessed aphrodisiac
qualities. St Jerome was so convinced that
he forbade their consumption by nuns! Roman writer Diogenes
Laertius explained that it was because they contain the souls
of the dead, a belief which was also held by the ancient Egyptians,
who, even though they cultivated them, regarded them as being unclean.
The Greeks, too held this same belief and some
scholars give as a supportive argument the fact that the Greek word, anemos,
can be translated as both wind and soul. For whatever reason, this
particular conviction was held very widely and almost all the ancient
societies used the broad bean as funerary
offerings or food in some way. Even the Celts, whose funeral
beanfeasts gave us the word beano.
Another argument which has been put forward for Pythagorus’
distrust of the bean is that he may have
been a sufferer of favism, a sensitivity to broad beans,
suffered by a very small number of people, especially in the
Mediterranean, which can lead to anaemia and jaundice.
Writers John Lyly and Thomas
Fuller opt for the more prosaic argument that the sage was
offering oblique advice to his followers to steer away from politics,
as the Greek voting system was based on the use of different coloured
beans. Jonathan Swift (1667-1745) certainly
had no doubts about the message, clearly stating where he stood on
the subject in his advice for conjugal bliss for newlyweds:
“Keep them to wholesome foods confin’d,
Nor let them taste what causes wind:
‘Tis this the sage of Samos means,
Forbidding his disciples beans.”
The French obviously held no such misgivings about the bean,
however: it is said that their common name is derived from the
French word for ‘good’, bien.
Nutritionally, the broad been is good. High in fibre,
low in fat, and contain iron, niacin, vitamin E and vitamin C and
100g provides a quarter of the daily requirement of phosphorous, good
for health bones and teeth. The shelled beans also contain
beta-carotene the vegetable form of vitamin A. Broad
beans have also hit the news recently as being another food
which may help to combat cancer - particularly cancer of the bowel.
Scientists have tested the effect of plant proteins, lectins, taken
from broad beans on colonic cancer cells and
found that they not only improved the ability of those cells to fight
the cancer but they also inhibited further growth. The findings, by
researchers at both Hammersmith Hospital and the Imperial College of
Science, Technology and Medicine, also show that they may help
malignant cells become more like normal, healthy cells. G.I. 79
Chick-pea - Cicer arietinum.
The pulse which gave its name to perhaps the most famous of the four
families were sold, mixed with lupin seeds, as a hot street snack in
Rome and evidence from archaeological sites in Palestine indicate
that it was used around 4,000BC. The specific name refers to the fact
that it was thought that the seed resembled the head of a ram, Aries.
In the Middle East it forms the basis for many of the dishes, such as
hummus (also the Arab name for the chick-pea), rendered into a paste
with garlic. In India it is known as channa and has been a
major food since the 2nd millennium BC. It is used in whole form, as
a dal (split) and can be milled into a fine flour, besan,
which is used to make pakoras, battered savouries. Chick-pea
flour is also popular in northern Italy, used to make the crisp,
light pastry for small pizze. G.I. 36
Common bean - Phaseolus vulgaris
Developed by selective breeding into hundreds of varieties, which
include the navy, field, pinto, black, haricot, dwarf and red kidney
beans, this branch of the family originates in South America. Each
variety is seen to fulfil a particular role: white with pork, black
with tortillas, and so on. Excavations at Peruvian sites have
revealed that Jack beans were being
cultivated in around 5,000BC and remains of kidney beans
have been found in Mexico which date back to around 3,000BC. Like a
lot of the foodstuffs from the continent, they were brought to Europe
courtesy by returning Spanish explorers, and rapidly established
their place as the most important family of legumes in Europe.
The first beans to reach
England, dark and kidney-shaped were duly dubbed ‘kidney
bean’ by the English, whilst the French gamely tried using the
Aztec ayacotl, which was soon turned into the more Gallic
sounding haricot. The most widely used bean
in the this country, mainly in the form of canned, baked
beans, is the navy or pea bean, so-called because it formed
part of the rations for the US Navy at one time. Another member of
this group which is popular in this country, the red
kidney bean, is an excellent source of dietary fibre,
potassium and folic acid and a good source of iron. G.I. 31
Lentil - Lens culinaris.
Probably the first cultivated legume, sometimes linked with wheat
and barley, which may have been domesticated at around the same time.
Its name is taken from the Latin word lens, which is now used
to describe a double-convex disc of glass - lentil-shaped. The
Bible (Genesis 25:29-34) describes how Esau,
the elder twin son of Isaac, sold his
birthright to his brother, Jacob, for a
bowl of lentil pottage.
It has the second highest protein content in the plant
kingdom, next to soy, at 25%. Which is why it is such a valued part
of any vegetarian diet, especially in Southeast Asia. It is probably
also why the lentil plays such a large part
in the devout Christian diet during Lent, replacing much of the
protein usually gained from meat products at other times of the year
- with the added bonus of the opportunity for that English pastime,
the play on words - in some areas they are still known as ‘Lent tills’.
The lentil is a good source
of dietary fibre, rich in folic acid and contains a good amount of
potassium. Also, as with the other grains and seeds, it contains
phytates, which may ward off cancerous changes in body cells. So, it
is good for you - but good enough to pass up the chance to father a
nation? G.I. 29
Mung bean - Vigna radiata.
More familiar in the West for the sprouted form which graces salad
bars from California to Bognor, this native of India has been grown
since prehistory for human and animal food, and to provide a form of
fertiliser. Producing several fast-growing crops a year, the bean is
an inexpensive and efficient food source. In India, the beans are
also milled, for use as a gram flour and split, as a dal. The split,
dried mung beans do not require soaking, as
with many other dried pulses, are easily digested and cooked
speedily. In China they are used in their sprouted form and as a
source of starch to make the almost transparent fen si
(cellophane noodles). They are a source of manganese, iron, folic
acid, magnesium and phosphorous. Sprouted, they are extremely low in
calories and high in vitamin C and fibre. G.I. 29
Pea - Pisum saativum.
Evidence of the use of field-peas and lentils has been found at a
site at Jarmo, in Iraq, which dates back to 6,500BC. Remains of peas
have also been found at prehistoric lake-site dwellings in
Switzerland and Iron Age settlements at Glastonbury. It was grown by
both the Greeks and Romans, spreading down to India, where it became
very popular. It was introduced into China in 7th century, where it
is known as hu tou (foreign legume).
The pea was an important
source of protein in the Middle Ages, pease pudding, made from split
peas, being almost a staple. When the garden pea made an appearance
in the 16th century, it caused quite a stir and, by the end of the
17th century, fashionable ladies on both sides of the Channel were
developing what might be regarded as an addiction for eating bowls of
small, fresh sweet peas (petit pois). In the Regency period, that
famous icon of ‘Polite Society’, George
‘Beau’ Brummell (1178-1840), when asked it was true
that he never touched vegetables, apparently replied, “I once
ate a pea”. Proof of the pea’s irresistable charm - or
its power to repel?
Peas are a fair source of
vitamin C, but are rich in vitamin B1 (thiamin), utilised by the body
for controlling energy release. They are also a good source of fibre.
However, fresh peas start to lose their nutrient value within hours
of being picked, making frozen peas, where this loss process is
halted, one of the best forms. G.I. 51 (fresh)
Runner Bean - Paseolus coccineus.
In Central America, where this variety originated, the indigenous
population use this variety for its roots, seeds and pods. It was
introduced into England in the time of Charles I,
by his gardener, Tradescant, for its
bright red flowers.
Nutritionally, they are similar to green peas, with a
similar amount of fibre, vitamin C and folic acid, 100g providing a
quarter of an adult non-smoker’s requirement for vitamin C and a
fifth of that for folate. However, it is estimated that up to a third
of these nutrients are lost to boiling. G.I. 51
Soy Bean - Glycine maximus.
The soy bean is thought to have first been cultivated in China in
the 3rd millennium BC, and it is mentioned in texts which go back as
far as 2,800BC. The first seeds were brought to Europe by German
botanist, Engelbert Kaenfer in 1692, but it
failed to make an impact in Europe at the time as, when treated
purely as a bean, the soy is less than
impressive, being bitter and tough. In India it enjoy slightly more
success and joined their repertoire of pulses under the guise of
white gram.
In fact the first use for this highly adaptable
foodstuff in the West was for purely industrial purposes, in such
things as paints, varnishes and soaps. However, with the advent of
the Second World War things changed. It was soon seen as an
invaluable padder for meat products like pies and sausages, an ideal
choice, for its amino acid balance is nearly as good as that of meat.
Other applications followed; with the invention of hydrogenation, soy
margarine appeared and, because of its high protein content, it was
soon being used for stock feed.
Soy milk, used by many people
who suffer from lactose intolerance, is made from crushed beans which
have been boiled and filtered, and has been used in China, where
dairy products are not generally consumed, since ancient times. Tofu
or bean curd, known as the ‘cheese of Asia’ is made by
grinding cooked soya beans to produce the
milk, which is then coagulated using calcium sulphate, making it a
good source of calcium, providing roughly a third of the average
daily requirement. It is high in protein, low in saturated fats,
cholesterol-free and 100g gives an energy value of 73 kcalories and
is a fair source of vitamin E and the mineral manganese. The soy
bean’s fibre is removed during tofu
processing, making it easier to digest, but fried tofu
can add to the calorie count, as it can absorb up to 15% of the fat
used to fry it in.
Soy sauce, the ‘salt and
pepper of the East’, appeared during the Zhou Dynasty
(1134-246BC) and was originally in the form of a thick paste called mesho.
Eventually this evolved into two products, shoyu,
the liquid sauce, and miso, a thick paste. It is made from soya
beans which have been fermented over a long period of time,
in the case of the ‘special’ sauces, years, and is
extremely high in sodium. Several versions of soy exist throughout
the East: the regular light and dark sauces (which also contain wheat
and hence unsuitable for those with gluten intolerance); Kecap,
an Indonesian variety made from black soy beans; Tamari, made
without wheat from whole beans.
Soya products are rich in
isoflavones - hormone-like substances that mimic the effect of
oestrogen, phytoestrogens - and these have come under close scrutiny
in recent years. It was noticed that Japanese women, who eat rather a
lot of soy in one form or another, rarely complain of the adverse
menopausal symptoms that seem to affect so many Western women.
Separate studies have also shown that women who enjoy a diet which is
rich in soya isoflavones had a lower rate of breast cancer
than women who don’t. Japanese men, too, seem to benefit from
this isoflavone-rich diet, with prostate cancer figures being
significantly lower than those for Western men. It is thought that
this may be due to the fact that a substance called genistein,
which blocks the growth of the capillaries which supply tumours with
blood, has been found in the urine of people who regularly eat
soya-rich food.
However, enthusiasm is for these effects is by no
means universal. Some scientists that although these and other
diseases, such as cardiovascular disease and osteoporosis, are lower
in such populations, we should beware of a ‘jumping on the
bandwagon’ reaction by flooding the market with phytoestrogen
supplements. They say that supplements may not have the same health
benefits as the substance as eaten in the foods; although soya
food products has been shown to lower blood cholesterol rates there
is, as yet, no evidence to show that the extracted phytoestrogen has
the same effect in isolation. In fact, some researchers who gave pure
phytoestrogens to animals, found that it did not protect them against
cancer and in one study, where animals were given genistein, the risk
of cancer actually increased. The underlying warning is, as in
traditional herbalism, ‘Nature probably knows best’;
substances in foodstuffs which are beneficial are better when not
taken out of the food matrix.
In fact, one research scientist, Dr
Richard Sharpe, of the Medical Research Council Reproductive
Biology Unit in Edinburgh, has gone on record as stating that he
definitely avoids buying anything containing soya
products for his children, despite the fact that it has been hailed
by so many as an anti-cancer agent. He says that he has seen results
of studies which show that, in female animals, soy
can produce the equivalent of premature menopause and that the
increased intake of oestrogens can lead to lower sperm counts in
males, “Until I have a reassurance that it doesn’t have
comparable effects on humans, I would rather not give it to my children.”
Professor Tom Sanders, of the Department
of Nutrition and Dietetics, King’s College, London, says that
the effect is not just restricted to children and that a soya-rich
diet has been found to have a feminising effect on vegan males and
that soya can disrupt the menstrual cycle in
women, “Many vegetarians don’t eat meat because they are
concerned about the hormone content, but the hormone content of soya
is much higher.”
The jury, it appears, is still out. G.I. 15 |