The Giant (East) African Snail (Achatina fulica), a terrestrial
gastropod, is considered one of "World's Worst invaders" amongst
agricultural pests.
In last few years an explosion of the giant snail population in India
is being reported as a serious threat to agriculture.
The Giant African snail has a voracious appetite and is known to feed
on upto 500 different types of fruit, vegetables, a wide variety of
ornamental plants, tree bark, and even paint, wreaking havoc on the
local vegetation and habitat.
Contrary to popular belief, the invasion of this pest in India is not
a recent phenomenon; in fact, the first occurrence of these snails
outside of Africa was in Bengal, India in 1847. Since then it has
spread throughout the world inadvertently and intentionally either on
ships, by plants, food source, as pets or for research.
These very large nocturnal snails grow up to 20 cm long overall, while
its light-brown shell (striped with cream bands) makes up half its
length. The snail’s life span is 3 to 5 years but they are known to
live up to 9 years.
The lack of predators and hardiness of the snail makes it dangerous because though it is
originally from a tropical area, it can survive cold and dry, hot,
inhospitable conditions by hibernating (dormant aestivation) in loose
soil. It calcifies the opening of its shell and is able to stay in
this state, underground, for up to 5 years, until favourable
conditions return.
The giant snails are essentially obligate-outcrossing hermaphrodite,
each having both female and male reproductive organs. Once it reaches
adulthood at six months, it just need be fertilized once to singly
produce 100 to 400 eggs in each clutch every three months, through the
rest of its life. In a year one snail can produce 1200 or more eggs
which it stores under the soil.
Getting rid of this pest has been ineffective both chemically and
biologically. Biologically, alien cannibalistic snails rosy wolfsnail
(Euglandina rosea) have been introduced with predictable consequences
of local, indigenous snail species being eaten. Manually gathering
the snails and destroying them by means of salt has been the most
advisable but not a very effective method.
In Africa, where these snails originate, they are a main source of
protein in the local’s diet in rural areas. In India, some tribal
communities like the Warlis consume indigenous snails species to
supplement their diets during monsoons.
However, information on the African giant snails as a food source has
not been explored in depth in India and instead, misconceptions and
misinformation has kept these snails out of the kitchens here.
Snails or escargot has been eaten throughout the world and been a
major source of free protein full of minerals and nutrition. In
fact, this giant specie is exported to Europe as a delicacy, either
canned or fresh. The average weight of a snail, sans the shell, is
approximately 32 grams.
The nutritional value of AF (Achatina fulica) per 100 gms of flesh is
as follows (Indian RDA used)
Protein – 10.08 gms (RDA women – 55 gms, men – 60 gms)
Calcium – 66.30 mg (RDA 600mg. comparatively liver 6, eggs 54 and milk 120)
Iron – 1.30 mg (RDA women - 21mg, men – 17mg. comparatively green
leafy vegs – 3 to 13, sardines 2.9, eggs 2.1 and milk 0.1)
Phosphorous – 14.79 mg
Magnesium -- 15.13 mg
Copper -- 0.58 mg (RDA 2mg)
As it is a low fat meat it is a good meat source for hypertension
patients. It is also a recommended diet in Nigeria for women and
children due to its calcium and iron content.
Processing or cleaning the snail for cooking is an important process.
The shell needs to be broken and the snail extracted. Cut away the
innards and the head portion separating the foot (body). The ‘foot’
then needs to be cleaned, either with alum, ash, vinegar or lemon,
further rinsing it with water to get rid of the slime. Once the flesh
is clear of slime it should be cut lengthwise and further into pieces
to then boiled to cook. The water it is boiled in may get white and
a little slimy, but continue to cook until the water is no longer
slimy (30 minutes). The snail is now ready to add to a recipe.
Below are a few links that give more information about the snail,
including a video showing how to prep the snail for cooking and
another that gives a tasty recipe.
This ‘pest’ has spread throughout India including in districts where
malnourishment is a major problem and there is an urgent need for
protein supplement.. More research needs to be conducted in India to
see how edible pests can be incorporated into one’s diet to enhance
the calorie count and nutrition of otherwise meager meals.
With global warming playing games with the climate and also creating
conducive conditions for pests to proliferate in the ever decreasing
‘food bowls’ of our country, we should learn to feed off whatever
mother nature has to offer in large quantities, be them insects or
snails. What better biological control of pests in this pesticide
filled era than to send the ultimate predator against them, man – it
is a win, win situation.
(Photo courtesy Wikicommons)
http://www.guardian.co.uk/
(video showing how to prep the snail for cooking)
https://www.shebafoods.com/
http://www.columbia.edu/itc/
(general info)
http://www.issg.org/database/
http://www.pjbs.org/pjnonline/
Pakistan Journal of Nutrition)
http://www.ncbi.nlm.nih.gov/
value of 4 other giant snails – Journal of Zhejiang University Science
B)
http://icmr.nic.in/guide/
