We probably all know this “Metallic
• Tastes/Smells Like: Metal, mainly iron, also described as tasting like pennies or blood, Felt on the front of the mouth and back of the throat
• Possible Causes: Wort being boiled in unprocessed metals, mainly iron, but also aluminum, and steel (excluding stainless) is usually the source of metallic flavors. Metallic avors can also be extracted from metal brewing equipment, bottle caps and/or kegs. Using water that has high levels of iron will impart iron avors. Improperly stored grains can also cause metallic off avors.
• How to Avoid: Use stainless steel pots and brewing equipment ( ttings, spoons, etc.) when possible. Avoid using iron for anything that will be coming in contact with beer/wort. If using a ceramic coated steel pot, always check for cracks or scratches before using. Stainless steel will not give off any metallic a- vors. Aluminum pots will generally only cause metal- lic avors when using alkaline water with a pH over 9. If using an aluminum pot, you can “bake” the pot in an oven at 250oF for 6 hours to increase the protec- tive oxides. Always use fresh, properly stored grain. Avoid using water with iron in it, such as un ltered well water.”
So i was thinking, if your beer is kegged, i would suspect the shank. Some of these are chromed, not stainless. That can impart a metallic taste when the chrome wears off.
