Does carbonation pressure remain in the line

[TexasGuy]

I am about to setup a kegged, non-beer, beverage. I found a fruit wine that is delicious when carbonated.

For dispensing, when I use several feet of hose to lower dispensing pressure, if I don’t dispense for a few weeks, does the carbonation of the fluid in the line remain the same as in the keg? The line and dispensing tap are both refrigerated.

 

[Bobby_M]

In theory yes but usually the lines are up the highest in the refrigerator where the temp is warmer so some CO2 does come out of solution. Further, most serving lines allow some oxygen ingress so that beverage is usually a little oxidized in the line. Best to dump the first ounce due to both.

 

[Vale71]

I am about to setup a kegged, non-beer, beverage. I found a fruit wine that is delicious when carbonated.

For dispensing, when I use several feet of hose to lower dispensing pressure, if I don’t dispense for a few weeks, does the carbonation of the fluid in the line remain the same as in the keg? The line and dispensing tap are both refrigerated.

As long as the line stays connected to the keg then yes. Even though most lines except for EVAbarrier and similar are quite permeable to gases, which means that in addition to O2 going in you'll also have CO2 escaping, if the line stays connected diffusion will cause CO2 from the beer in the keg to be uniformly distributed so that it will continuously replace the CO2 that was lost through the line. Overall your beverage will lose some carbonation with time but unless your lines are incredibly long it is a very slow process so that your main worry is still oxygen ingress rather than loss of carbonation.
If you detach the serving line then the small amount of beverage trapped inside could suffer from significant loss of carbonation but again, unless your lines are incredibly long it will be a very small amount of beverage that will amount to just a little sip so that when you serve again it will mix with the fully carbonated beverage from the keg.