In the Abyss, the same map where you open up the door to the Sunken City, in the top left part of the map, you have a big 'loop', but within that loop, there is a spot, two tubes from the top and from the bottom lead to the middle, I believe there is a cold borscht there.
The tube is hidden by darker spikes that seem to 'obstruct' your way in there.
I hope you know what I'm describing. And I hope it's there.