I just tasted my last beer, a “grapefruit” bitter, and it’s lemony. SO lemony. My ESB (before that) was fairly lemony too. I sanitise well, I’m confident of that, but my kids knocked the airlock of this beer three times. I think it’s either bad yeast, not rinsing out the starsan foam, sparging the grains with too hot water (or getting them too close to boiling) or it’s just too green. I doubt the last one, because my bitter never really lost the lemony taste – although it did diminish.
So I need your help, any of you beer experts! Do you think it just got contaminated because of the airlock? Better ideas?