is drinking even one sip of alcohal haram, with the intent of trying only once.

All perfect praise be to Allaah, The Lord of the Worlds. I testify that there is none worthy of worship except Allaah, and that Muhammad is His slave and Messenger.

It is not permissible to drink any amount of intoxicants no matter how small it is even if the drinking is for the purpose of trying as you mentioned. We do not know why you want to try it!

If consuming a big quantity of alcohol [or any kind of intoxicant] causes drunkenness, then consuming a small quantity of it is forbidden as confirmed in the authentic Sunnah from the Prophet . For more benefit, please refer to Fataawa 81461 and 81567.

Some scholars forbade consuming alcohol [or any kind of intoxicant] in case of necessity except if one chokes with his food (and does not find other than alcohol to wash it down). Based on this, the prohibition of consuming alcohol to try it is much more confirmed.

Therefore, a Muslim should be careful lest the devil will deceive him gradually in such a case until he becomes a consumer of alcohol and then becomes addicted to it, and so, he would lose his religion and his worldly life. Allaah Says (what means): {O you who have believed, do not follow the footsteps of Satan. And whoever follows the footsteps of Satan — indeed, he enjoins immorality and wrongdoing.}[Quran 24:21]

Allaah Knows best.