Question regarding a scale or sensor for a project

I have an idea for a game, a beer drinking game called Chug a Glug. This is a game with three challenges that must be performed in order, and within a specified time. This game will include the use of an Arduino to run the program, a pitcher of beer, two mugs marked at 5 glugs and 3 glugs, and a scale (or pressure sensor) that can be interfaced with the Arduino. The first challenge is to measure 1 glug. The second challenge is to measure 2 glugs, and the third challenge is to measure 4 glugs. For each challenge, the player will place the mug of measured beer on the scale, slap a large red button, then chug the beer before the next challenge. A buzzer will sound if a challenge is not met, allowing the player another chance. All three challenges must be completed before the time is up or an alarm will sound (dee-daw siren?). I believe that I can program for the game, but I am not sure what to use for a scale. Is there a scale or pressure sensor that will work for this? It will need to output a value that the Arduino can read (digital, analog?). Another thing that occurred to me is that beer may be foamy, making the measure difficult. Some skill at pouring may be necessary. I can adjust MIN/MAX weight variables to make it fair, while keeping it difficult to estimate. This is an old puzzle with a twist. Losers still get to drink beer! A non-alcoholic version can be developed to demonstrate the puzzles too