Kochi: With the Mandalam season already underway, Ayyappan Pattu rituals are in full swing across Central Kerala, and so is the workload of the artisans who craft the udukku, the traditional percussion instrument integral to these ceremonies.

Despite its simple appearance, the udukku requires meticulous craftsmanship, and only a small group of artisans still possess the specialised skills needed to make it. Besides Ayyappan Pattu, the instrument is indispensable in several musical rituals connected to the Sabarimala pilgrimage, including Sasthampattu and Udukkadichaan Pattu.

The key components of the udukku include its central portion, known as the nazhi, the leather stretched across both sides, and the metal ring to which the leather is fastened. The nazhi or frame is made of either wood or metal. The leather that produces the instrument’s distinct sound is fixed onto the nazhi using metal rings.

Another crucial part is the kacha, the component that generates the sound. Among the types of wood used for making the nazhi, the most common are golden shower tree (Kanikkonna), dwarf white bauhinia (mandaram), jackfruit, oleander and mahogany. When the nazhi is made of metal, brass or aluminium is typically used. Traditionally, the inner skin of cattle intestines, locally known as ulloori, was used as the leather covering, though fibre and metallic gold paper have increasingly replaced it today.

The glue used to make udukku is a unique mixture prepared by boiling raw rice with copper sulphate and grinding it into a fine paste.

According to Hariprasad, a native of Edavanakkadu who has been crafting the instrument for several years, the most intricate part of the process is the winding of the twine (naaru), which controls the tone the udukku produces.

The udukku is played using only the ring finger and the index finger. Across central Kerala, it is widely used as the accompanying instrument for Ayyappan Pattu rituals, and its demand surges during the annual Mandalam pilgrimage season.