Idioglot double reeds (tubular reeds) have a natural tendency to return to their open, round condition when wet, making them harder to play. I find that ‘toasting’ the reed helps to maintain a closed tip. This is done as a matter of course with Duduk and Mey reeds, various bagpipe reeds, and even clarinet reeds in some cultures, especially Albania and Turkey.
First, put a clamp on the reed when it is completely dry, covering the top third or half of the blades. Then dab oil (olive, canola, almond…) on the exposed part of the blades. The oil will lightly penetrate the cane, and when heated will form a protective layer acting as a preservative to a small degree. Heat the entire exposed surface of the blades, not neglecting the sides, until it begins to show signs of browning. You can also include the tube below the waist, especially if the rind has been stripped away, being very careful not to burn the binding. I prefer natural fibres over synthetics for the binding. They are less prone to damage during toasting, and in general seem to have a better chance of maintaining the proper tension. If the binding does burn, quickly rebind the waist while the reed is still hot, taking advantage of its temporary plastic state. While still hot, compress the back of the reed firmly for a minute or so between your fingers and thumbs to fix the reed blades close together (in the video above, I abbreviate this step). It will cool within a few minutes and be ready to finish scraping.
I use a Bernzomatic micro torch (http://www.bernzomatic.com/products/hand-torches/) with the heating tip in place. I have come to prefer this to an open flame as it is much more controllable. A gas hob works fine, as does charcoal, an alcohol lamp or industrial heat gun, the only issue is focusing the heat in the proper area, and using a clean heat source which will not leave residue in its wake. I’ve tried toasting the entire reed and not had much luck. I have found though, that it is possible to bake a reed which is too light. A low heat (about 250 Fahrenheit or 120 Celsius) for half an hour or so will give it some more stiffness. Radical, but it does work.
I generally toast before the final scraping, so that if it comes out overly hard one can compensate. Toasted cane will still be somewhat malleable when wet, and if the form needs some touchup, reheating while the reed is wet will be more successful than retoasting, as there is a limit, a point at which the reed chars rather than toasts, and begins to lose its elasticity. One can also harden soft reeds using the same method, being quite delicate when approaching the tip area.
The inside of the reed may be wiped with canola (rapeseed or ‘vegetable’) oil – initially when first dried and occasionally throughout its lifespan. A heavier oil will impair the reed’s vibration, but a very light oil will lengthen the reed’s useful life. I have found that alcohol has no preservative effect on reeds, but many people disinfect a reed in either alcohol, mouthwash, or H2O2 (hydrogen peroxide). These, however, will dissolve any oil previously applied, so the two methods may be considered mutually exclusive. H2O2 is actually much more effective for cleaning and disinfecting reeds than any sort of solvent, and has fewer harmful effects on the cane. Alcohol eventually depletes the cane of some of its natural sugars, which are essential to its elastic properties.