Surah 83. Al-Mutaffifin, Ayah 25

The Wine will be of the utmost purity and flavour, so precious that it will be protected with a seal, and the seal itself will be of the costly material of musk, which is most highly esteemed in the East for its perfume. Perhaps a better interpretation of the "seal" is to take it as implying the final effect of the drink: just as a seal close a document, so the seal of the drink will be the final effect of the delicious perfume and flavour of musk, heightening the enjoyment and helping in the digestion.