The requirements are normally laid down in the operations manual. They will be based on the air law relevant to the jurisdiction, but they can vary from company to company. Usually you will find a restiction of anything from 8 to 12 hours after the consumption of any acohol before commencing a flying or standby duty. This period will be extended to at least 14 hours for anything more than a moderate intake.
Obviously the metabolic rate of absorption can vary from person to person and whatever the limit may actually be, your own performance can be sufficiently degraded after the statutory period such that you are not fit to fly.
I would suggest that playing with the limits in this case is a dangerous game to play in any jurisdiction.