Strong salty, baking-soda like flavor in Rum distilate

[Dman]

Hey Home distillers. Been ages since I’ve visited this forum. Good to be back.


I ran an experimental batch of high ester Rum, and this one resulted in a very odd, baking-soda like bite. Something similar only happened to me once before, and I found I was unable to distill this flavor out (going to try it on this batch as well). First thing I am concerned about is whether it's safe to drink.
The process was as following:

Fermentation:
20% dunder
All blackstrap for sugar, 1.098 S.G.
Nutrient was a mix of DAP and Valine + Leucine amino acids
1 multivitamin + 1 b complex (come to think of it, I think I might have done this last time I got this off flavor as well)
100g dead yeast
Pre-fermentation, added 10% of lactic bacteria, Panella fermentation.
Yeast was a Hernendal Kveik


Distillation:
Ran this through a double retort. First thumper was copper (primed with Rum tails), 2nd was stainless steel (primed with rum heads). I primed both of them with 1.5ml of sulfuric acid to promote cousins esterification.
What I didn’t realize is that stainless steel is corroded by sulfuric acid. The high wines in the steel thumper were cobalt blue. Though none of that color made it through to the distillate.
The copper thumper low wines were pretty deep yellow (which is also a first for me). Don't think it was due to puking as there was an union before the 1st thumper.

Any ideas of whatI might be tasting?