My Mild has developed an off flavour?

[BlightyBrewer]

I've been enjoying my English Mild for a week or so, which I have kegged, with 8 bottles put aside to mature. Anyways, the taste has been pretty good, but as I have reached the bottom of the keg I "induced" a little Oxygen as the presssure from the CO2 had dropped. I recharged the keg with CO2, but now the taste has changed. It now has a strange fruity and plastic kind of taste. It reminds me of my last brew, and English Bitter. I thought this was the flavour from the Cascade hops, but my for my mild I used Fuggles hops, and as I say the taste has changed to something similar to my English Bitter...which makes me think that that flavour was not the hops, but an off flavour?

Can anyone shed some light on this?

 

[david_42]

Milds can develop off flavors if you are using the keg as a secondary/conditioning setup. Lower hops levels are the main problem. Try keeping the keg as cool as possible after the secondary ferment. This will force the remaining yeast to go dormant rather than dying. I always try to have a space in the keggerator for the Mild, even if this means having to drink an extra pint or two to float the old one. :cross:

 

[BlightyBrewer]

Dead yeast? Would this also explain why my mild was as flat as a Dutch landscape?