Well we'll just cut to the chase and let you know that no, Red Bull does not contain bull semen, nor do other common energy drinks. Red Bull has commented on this rumor and story and confirmed that not the energy drink Red Bull does not contain bull semen. But as is often the case with these food myths and urban legends, despite having been debunked, they tend to continue to make the rounds every couple of years and once again this rumor is trending online.
For some reason this urban legend always tends to involve the ingredient Taurine, a common ingredient in energy drinks which is a naturally occuring sulfur containing amino acid concentrated in our eyes, heart and muscles. Taurine is not made from or derived from bull testicles or bull semen, the taurine in Red Bull and most other energy drinks is produced synthetically by pharmaceutical companies. If you're curious where the tie in between bull semen and taurine comes from, the name Taurine is derived from the Latin "Tauras" which means bull or ox, because taurine was initially isolated from ox bile way back in 1827 by a German Scientist named Friedrich Tiedemann. While taurine today is produced synthetically in labs, somehow internet misinformation spreaders keep perpetuating the rumor that Red Bull contains bull semen, however you can rest assured that next time your sucking down a can of Red Bull you will not be consuming bull semen.