Black sediment in my mead

[Johnny2]

I used calcium carbonate to raise the pH and didn't do cold stabilization as I don't have space to do that and I though red currants have mostly citric acid in them.
I had this same occurrence in my last bottle of red currant wine

Question number one: Why is it black? Shouldn't wine diamonds be clear or white.

Question number two: Is this same issue when using potassium, or potassium bicarbonate?

 

[MightyMosin]

It is normally white. I don't know if what you are seeing is the result of looking at it through the mead.

I rarely adjust pH up prior to fermentation. I'm curious what was the pH prior to adjusting and what did you adjust it to? Pre or post fermentation?

 

[Johnny2]

From 2.x to 3.1 - 3.3 pre fermentation. My strips only show down to 2.8, so I don't know if it was 2.4 or 2.8, 10g in 10l.

Should be more like dark brown.

 

[MightyMosin]

I've seen them colored by the wine they are in, similar to that image.

I'm not sure how accurate test strips are but I have done mead that started with a pH right about 3.0. You can add the carbonate to provide buffering without needing to actually raise the pH higher; you are just trying to prevent it from crashing lower.

Chances are the fruits in primary will help with that. If you have the availability of Lalvin 71B yeast, it is a great choice as it will be a malo-ethanolic conversion and chew through some of your malic acid and actually increase the pH. In the waterless mead that I recently did, it started at a pH of 3.3 and when fermentation was done it was sitting at 4.0.

 

[Johnny2]

But there are fruits and berries with a ph in the 2 range, like currants, cranberries and some citrus fruits. And on those I've used something, usually CaCO, but I also recently bought "lab grade" potassium carbonate, which I'm not sure if i should use and food grade potassium bicarbonate, which I used on my latest "Skeeter Blood".

They are not always easy to read, but gets the job done. https://brouwland.com/en/ph-measurement/10370-ph-test-strip-28-46-wine-comboucha-20-pc.html