I grabbed a couple kegs from an old friend a while back. When I picked them up they were pressurized and had liquid in them. My friend made a joke that it must be 20 year old beer. When I opened them at home there was about a gallon of soda syrup in them. Apparently he had bought a lot of equipment from soda companies back in the 80's or 90's with the plan to start a brew shop. I rinsed them out, then soaked them with oxy-clean for a few hours and scrubbed them the best I could. I couldn't smell anything leftover, so I brewed a bunch of beer for a party two months ago.
The left overs of a Honey Wheat Ale were left in this keg until this week when I tapped it. During the party it was great. Yesterday when I pulled a glass it tasted like soda syrup tainted beer. Has anyone every had this happen to them from old kegs? How can I make sure it doesn't happen again? The second syrupy keg I put a Jubel Ale clone in it so it either didn't have the problem or covered the off flavor enough where I didn't notice.