In
the Viet kitchen, rau muong may be stir-fried with garlic
and heady seasonings like shrimp sauce, featured in refreshing salads,
pickled, and used as garnish for noodle soup. Similar to Western
spinach but with somewhat crunchy stems, water spinach is easy to
grow. It flourishes so well in hot areas that in parts of the U.S.,
such as Florida and Texas, it's been deemed a weed. In the summer,
you'll find it in abundance at Asian markets. Prices are downright
cheap but they'll go up when the temps drop.
Per
Charmain Solomon's Encyclopedia of Asian Food, water spinach
goes by these names in Asia:
China:
ong choy, ung tsai India: kalmua Indonesia: kangkung Japan: kankon Malaysia: kangkung Phillippines: kangkong Sri Lanka: kangkung Thailand: pak boong Vietnam: rau muong
Water spinach
(rau muong) is a much loved vegetable in Vietnam, particularly
in the northern region. People have a great affinity for water spinach
because it is one of the chief leafy green vegetables in the Vietnamese
diet, just like it is in southern China and other Southeast Asian countries.
But where did it come from? That is the question posed by a geography
doctoral candidate in England. I didn't have the full story, so I asked
some fellow experts for help. Below is what they offered.
Question:
Hi Andrea,
I just
visited your website and can't help but be amazed at the tons of information
on Vietnamese cooking. Going through some of the recipes listed brings
me back to my food experience in Hanoi and other lovely places in Vietnam.
It was wonderful. Kudos!
I am a
PhD student doing research on the rau mong (water spinach) producers
in Hanoi, Bangkok and Phnom Penh. I am interested in primarily finding
out the characteristics of households involved in its production and
identify whether here are differences in how it is being produced within
these cities. A corollary interest that I wanted to find out is the
history of this vegetable. It's considered a noxious weed in other places,
but holds an important role in Southeast Asian table. It is with respect
to the latter that I am sending this query to you. I am wondering whether
you are aware of any literature on the history of this vegetable whether
local (e.g., Vietnam) or regional as in how it came to Southeast Asia.
Any leads, books, articles or websites, though remotely related, is
very much appreciated.
Thanks.
Best regards,
a l b e
r t
My
response:
Dear Albert,
What a
terrific research project you have going. You may want to include mention
of the Chinese. Water spinach is very popular in southern China and
Taiwan. Per Bruce Cost's Asian Ingredients, water spinach is
a native of tropical India. I've yet to find little else. However, I've
emailed several people and asked if they may assist you.
Andrea
Daniel
Harder, director
of the UC
Santa Cruz Arboretum
and a botanist who conducts research in Vietnam, contributed:
Water spinach
(swamp morning glory) is Ipomoea aquatica (Convolulaceae) a very
popular and tasty vegetable. Usually, like Sechium edule, Cucurbitacae
(or chayote) the young shoots and leaves are eaten as a vegetable. I
found a reference to its use as a emetic in Burma (Myanmar) for opium
poisoning.
I have
seen it in tropical and subtropical areas including central Africa,
Indochina, in Hawai'i and in Australia and now is common in local markets.
It is considered a noxious weed worldwide and in warmer parts of the
US. Because it grows near water and has hollow stems for floating, it
spreads rapidly by rooting and spreading seeds.
Its place
of origin is a bit disputed and misunderstood usually indicating a long
history of cultivation and migration of the plant especially associated
with water (for easy dispersal). It is listed in some references as
being native to Central and Southern China (with earliest historical
record), yet also India and Southeast Asia. Mr Salamanaca [Dan actually
meant Bruce Cost] may be right and I am not sure anyone will say authoritatively.
I suggest mentioning the confusion in knowing its purported place of
origin.
If I were
investigating the origin, I would look at the distribution of close
genetic wild relatives of Ipomoea aquatica because it may be
of hybrid origin or has become significantly different from its wild
precursor through selection and semi-domestication. In this case, the
more regional diversity among close relatives can suggest region of
origin. One might look at the incidence of restricted viruses and disease
susceptibility. Regions of origin sometimes have greater incidence of
obligate host diseases. Collecting the long list of common names in
use and historically may allow one to reconstruct a plausible lineage
through derivative naming and known plant/human migration routes.
Gene
Anderson, professor of anthropology at UC Riverside and author of The
Food of China, responded with:
Ipomoea
aquatica
is found, and eaten, all over tropical and subtropical Asia. It is grown
now widely in the western hemisphere too — in California by Vietnamese
and Chinese gardeners, and I think similarly in other warm parts of
the US and probably Latin America. It appears to be native from India
around to China. It first appears in the Nanfang Zaomu Zhuang,
a botanical work of the 5th century AD (with some later additions —
but the water spinach probably goes back to the beginning of the book).
So it was considered a southern product then, and still is. It's universal
in south China — everybody grows it wherever they can find a little
permanent water. I saw it all over Hong Kong and Guangdong and so on.
So it definitely is not an especially Vietnamese plant. The Chinese
name is yongcai (pronounced yung-ts'ai or locally weng-ts'ai etc). Every
Asian market in the US seems to carry it. It's medicinal — used
for a diuretic and to treat constipation etc, and it actually does have
a lot of liquid, vitamins (lots of vitamin A), and minerals.
I
forwarded these comments and Albert wrote back:
Hi Andrea,
A million
thanks for all the help. It's so nice of you to personally send out
queries to those well-known people. The info they provided helps a lot.
Best regards,
a l b e
r t
Then
Albert sent additional information that he received from Dan Austin, a
research associate at Arizona-Sonora Desert Museum
and expert on Convolulaceae (the rau muong family):
I. aquatica
is
NATIVE to southeastern Asia and has long been cultivated there. From
there, it was introduced into the New World several times. The first
that I ever found records of was in the early 1900s by a fellow working
at the University of Miami. Then, as all the Asian immigrants came to
live in the USA, they brought along the plants (or had their relatives
send them to them). They had been growning I. aquatica for a long time
before it escaped and caught the attention of the State and Federal
people. Even then, especially the Thais that I knew, continued growing
it and simply told the inadequately trained inspectors to their nurseries
that it was something else. It probably is still grown, but I am 5 years
out of touch with Florida since I moved to Arizona.
You should
also consult this book -- Committee, E., Ed. (1995). Flora of China.
Volume 16. Gentianaceae through Boraginaceae. St. Louis, MO, Missouri
Botanical Garden (Fang, Rhui-cheng and Staples, Convolvulaceae, Pp.
271-325). Or, if that is not available, check the flora online site
at www.efloras.org
My colleague
George Staples co-wrote that with his Chinese counterpart. George also
has just done the family for the Flora of Thailand (he just returned
home from writing it), but it will be some time before it is published.
He and
another colleague did this: Yang, S. and G. W. Staples (1998). "Convolvulaceae
in Flora of Taiwan." Flora of Taiwan, Second Edition. E.
Committee. Taipei, Taipei, ROC, National Taiwan University. 4: 341-383,
1137-1140.
