Which type of line tubing should not be bundled due to oxygen permeability?

Vinyl tubing is not recommended to be bundled due to its oxygen permeability. This type of tubing can allow oxygen to permeate through its walls, which can lead to oxidation of beer or other beverages. When bundled with additional tubing, the potential for increased oxygen exposure is heightened, which is particularly detrimental in environments where maintaining the integrity of the beverage is crucial.

In contrast, barrier tubing is specifically designed to limit oxygen transfer and protect the product within from oxidative spoilage. Stainless steel tubing is non-permeable and effectively prevents any gas transfer, making it an excellent choice for maintaining beverage quality. Similarly, while certain types of PVC tubing have some resistance to oxygen permeability, they are generally not as effective as barrier tubing. Thus, it is the unique characteristic of vinyl tubing, its ability to allow oxygen ingress, that necessitates caution against bundling.