Table of Contents
Hermann, M. 1996. Starch noodles from edible canna. p.
507-508. In: J. Janick (ed.), Progress in new crops. ASHS Press, Arlington,
Starch Noodles from Edible Canna
Edible canna (Canna edulis Ker-Gawler, Cannaceae) is a starchy root crop
with historic importance but is little used today in its native Andean range.
Although of pantropical distribution, it is infrequently grown and mostly used
as an emergency food. Direct consumption of the fibrous rhizome is limited by
its poor eating quality and its long cooking time (2 to 5 hours).
Canna is easy to grow. It has no significant pests or diseases. The crop
thrives on residual nutrients and can be grown continuously. Typically
yielding 20-40 t per ha, canna is often grown without irrigation on marginal
soils or on slopes where its long crop duration (10-12 months) helps prevent
Nowhere else is canna as important as in north Vietnam where, over the last 30
years, the area in canna has expanded to an estimated 20,000-30,000 ha. Canna
is grown for the sole purpose of extracting starch. Wooden drum graters and
simple sedimentation tanks are used to extract the starch. Canna starch has the
largest known granules (30-100 mm), resulting in fast settling. The rhizomes
contain 22% to 25% of dry matter and starch yields range from 12% to 16%.
The overwhelming portion of canna starch production in Vietnam is processed
into transparent starch noodles ("cellophane noodles"), a luxury food of
south-east Asia and traditionally made of costly mungbean starch. Good
cellophane noodles are about 1 mm thick; they display high tensile strength and
good transparency. Dry matter loss during prolonged cooking is less than 10%.
Starch noodles of non-canna origin are usually produced through extrusion
cooking, which requires the extruded noodles to pass through a cooling water
bath. By contrast, canna noodles are manufactured by a different, and
previously undescribed, process involving the steam-sheeting of a starch/water
dough. The resulting gel sheets are stretched and semi-dried on bamboo frames.
The gel sheets are then folded and cut into straight noodles. They are finally
dried to a moisture content of about 18% to 21%.
Canna noodles in Vietnam have excellent eating quality, much superior to
extrusion noodles made experimentally from sweet potato and cassava starches
which are widely available in southeast Asia. Special but as yet poorly
understood functional properties of canna starch make it a substitute which has
totally replaced expensive mungbean starch as the raw material for cellophane
noodles in Vietnam. The high amylose content (25% to 30%) of canna starch as
compared with other root starches has been proposed to explain the high peak
viscosity observed during gelatinization, which permits the sheets to be easily
handled. Canna starch also displays high gel retrogradation
(recrystallization) and transparency which is critical to noodle quality.
Canna processing in Vietnam provides employment to many thousands of people in
rural communities with as little as 500 m2 of arable land per
capita. Canna use in Vietnam shows how product development can provide new
perspectives for crop utilization and stimulate demand for otherwise obsolete
||Fig 1. Canna production and noodle processing in Vietnam. A: Muong girl cleaning canna rhizomes (Tu Ly, Hoa Binh Province, 400 m altitude);
||B: Canna market in Duong Lieu (Ha Tay Province, Red River Delta);
||C: Canna starch extraction plant (Duong Lieu, Ha Tay Province);
||D: Drying of canna starch (Duong Lieu, Ha Tay Province);
||E: Steam-sheeting of canna starch dough (Duong
Lieu, Ha Tay Province);
||F: Stretching canna starch gels (Duong Lieu, Ha Tay
||G: Canna noodles on sale (Central Market, Hanoi). (Photographs taken November 1992, all north Vietnam).
Last update August 24, 1997