Pepsi Cola and Coca-Cola in Space

The year was 1984 - Coca-Cola asked NASA whether it was possible to drink a carbonated Coke in space. Unsuspecting, NASA gave the GO for a small experiment. In the experiment called Carbonated Beverage Dispenser Evaluation (CBDE), the astronauts were supposed to try out a Coke can specially developed for space and drink from it in zero gravity.
However, this got through to the competitor Pepsi and NASA agreed to postpone the experiment so that Pepsi would also have the opportunity to develop a space can.

But unfortunately, the beverage manufacturers constantly had conflicting special requests, so it slowly dawned on NASA that they were being used as an advertising tool here - and the astronauts were also annoyed by the constantly changing instructions. Loren Acton, who was in charge of the laboratory as payload specialist during the flight, explained that the action with the beverage cans took up more time and attention than the preparation for the really important experiments.

So the crew flew into space in 1985 and conducted experiments with two different teams in 12-hour shifts, with team "blue" getting the four Coca-Colas to test and team "red" testing the Pepsi cans.

All the experiments turned out rather mediocre, which is also due to the problem of weightlessness. For while gravity pulls liquids and food downwards, and the excess carbon dioxide easily escapes through burping, this natural separation mechanism is missing in space. Liquids move freely in space and belching causes vomiting. The result: gastric distress. Loss of appetite and flatulence.

Although the idea of the space cola did not catch on, it was still a marketing hit for Pepsi and Coca-Cola. For science, on the other hand, the value was manageable, because it had actually been foreseeable that carbonated drinks are only suitable for weightlessness to a very limited extent.