At what angle should the bottle be held while filling it?

Holding the bottle at a 45-degree angle while filling it is optimal for several reasons. This position allows for a controlled and more efficient flow of liquid into the bottle, minimizing the risk of splashing or overfilling. At a 45-degree angle, the opening of the bottle is partially aligned with the stream of liquid, which helps direct the flow smoothly into the container rather than causing it to hit the sides too hard or create excessive turbulence.

Additionally, this angle helps to ensure that air can escape from the bottle as it fills up, which is essential for preventing pressure build-up and facilitating a more even fill. Other angles, such as 30 or 60 degrees, might not provide the same level of effectiveness in controlling the flow and could lead to more spills or a longer filling time. Holding the bottle vertically at 90 degrees could result in a fast fill but might also lead to increased splashing due to the liquid entering too abruptly. Therefore, maintaining the bottle at a 45-degree angle is the best practice when filling to achieve a balance between efficiency and control.