The Chufa is cultivated in seventeen municipalities of the Valencian region of Horta Nord, as their land has the required characteristics and climate. Therefore, this is the only area in Spain where this so specific tuber is grown. In this region, about 5300 tons of dry chufa are currently produced, of which about 90% are protected by the D.O..
The Chufa of Valencia (Cyperus esculentus) is a plant of about 40 to 50 cm in height. It has a complex system of fine, fibrous roots completed with rhizomes at which end are formed the Chufas. Those may have two shapes: llargeta (=oblong) or armela (= spherical).
CULTIVATION
Some soil preparation has to be done before the seeding as the soil has to be flat, spongy and very soft, hence the machinery used for seeding has to be light to avoid problems of compacting the soil. We use tractors of 25-70 HP.
The Chufa is planted during the months of April and May, date which depends on the previous culture. The seeding is mechanical and is done in seed-beds elevated by 20 cm from the ridges, and the separation between ridges is of about 60 cm. The seeding depth varies between 6-8 cm in the prepared soil.
The density of the seeding is an important aspect of the culture as the crop yields as well as the quality of the tuber depend largely on it. Therefore, there is an optimal density which should not be exceeded at the risk that plants fray and lie prematurely. This optimal density is of about 120 to 135 kg per ha (10 to 11,25 kg per fanega).
For optimal cultivation conditions of the Chufa some requirements must be observed:
- Climate requirements: In hot climates like the Valencian, with high average temperatures, a quite elevated humid atmosphere and a frost-free period of 4-5 months, the plant can complete its vegetative cycle without any problem.
- Soil requirements: If the goal is to obtain a quality product, the cultivation of the chufa has to be done in soils which have specific characteristics. Suitable soils for the culture of the Chufa must be soft, so as to get the required quality of the tubers, a good crop yield and an easy recollection as a soil depth of 15-20 cm has to be sieved and this is obviously better done with soft soils. Furthermore, soils where the Chufa is cultivated must be well-drained, levelled, free from weeds and stones and also enriched with mature or compost.
HARVEST
A harvester with a cut-bar of a width which covers two or three seed-beds is used for this purpose. This bar cuts the soil under the tigernut plant, pulls it out, crumbles the ground with a bar milling and deposits everything in a screener bucket which separates the soil from the Chufa. The tigernuts come out at the rear of the harvester together with rests of the plant, small stones, etc. and everything is transported by a conveyor belt to the trailer of the tractor.
Then, the monitored scorching of the leaves is done, followed by a cleaning of the ashes and remains.
As the plant has to be completely withered and dry, harvesting will occur during the period November to January.
WASHING
After harvesting comes washing. During this procedure, the Chufas will lose their roots, their skin will be washed and the defect tubers will be eliminated.
So, the Chufas which have just been harvested are at the beginning deposited in part of the washing-area. The harvest goes then through drums which separate the soil from the rest and where the tuber hairs are eliminated from the Chufa. Then they will be showered and go through gutters where different water-sprayers will remove the gravels from the Chufas.
DRYING
Once clean, the Chufas are going to lose their humidity through the drying process.
There, humidity will be reduced from 50% to 11%. This procedure, which usually takes three months, is accomplished very slowly and carefully in “drying-attics”. During this period, the Chufas have to be turned twice every day to ensure uniform drying. The frequency of this operation decreases progressively based on the humidity lost.
CLEANING AND CLASSIFICATION
When dry, the Chufas are cleaned again to remove impurities which remained after the washing. Then they are classified in sizes and at the same time the defective tubers or the ones which are too small are removed. These rests are called the trimmings.
Finally, a manual complementary selection is done. It is then that the Chufas are packaged and are ready for the preparation of the Horchata.
