Hola Mariana, te adjunto lo que encontré en Internet:

http://images.google.com/imgres?imgurl=http://bp3.blogger.co...

Este sitio está en inglés. Habla del proceso para la protección integral de la fragancia.
Por lo que parece, esto se hace con una membrana protectora sintética latex:

We made our way inside and up a tiny lift where we learned the art of baudruche. It’s a process intended to protect the integrity of the fragrance. It involves stretching a synthetic membrane tautly around the bottle, securing it with an artfully tied knot (above), and then cutting the excess away (below). Afterwards, using hot black wax and a stamp, the interlocking C logo is pressed over the unfinished knot for aesthetic refinement. I took a stab at the membrane wrapping, only to produce what looked like one of those vacuum-sealed hotdog packages that had been punctured and, now partially filled with air, is tossed to the back of the supermarket fridge. Twisted, lumpy, and worst of all, loose. No Baudruche Degree for me.

http://www.google.com.uy/search?hl=es&q=sellado + perfumes&b...

De todo esto deduzco, que baudruchage sería simplemente el sellado.

Suerte y espera otras opiniones.