Problems with sourdough sourness
I love a really tangy sourdough - problem is, no matter what I try, I'm failing to get even a recognizable sourdough taste in my loaves. I've tried very long bulk proofs, retarding loaves for 24 hours, using more salt, inoculating with very small amounts, different hydrations, different proportions of whole wheat and rye, and less hydrated starters. All of which produce a loaf that other people don't even recognize as sourdough. In an attempt to squeeze out a little tang, I made a 50% hydration starter with 200g of a 500g loaf and let it sit for 48 hours. It smelled of fruit and alcohol, but no tang in the finished loaf (didn't care about crumb, just wanted to see if I could get some sourness).
I've produced about 30 loaves trying to come up with a recognizable sourness and am failing... they keep coming out with no tang what-so-ever.
The starter I'm using was created about 3 years ago by me. It triples at 8 hours after feeding.
I feel like I have covered all my bases to produce a sour loaf, the only other thing I can think of is maybe it's my starter. Is there a chance that my starter just doesn't make the sourness I'm looking for? Could it have become contaminated with commercial yeast?
I would love anyone's input and suggestions, or if anyone else has had this issue.