High final Brix reading, 1.00 SG

Question

I recently received a refractometer and tried it out on a batch of mead that has been in secondary for about 3 months.

I took a reading of some distilled water, both read 1.00. I then dissolved 30g of sugar into 250ml of water and took a reading; both showed around 1.045.

However, when I measure my mead, I get pretty much exactly 1.00 on the hydrometer but 10 brix (1.040 sg) on the refractometer.

Interestingly, the mead tastes quite sweet; much sweeter than I'd expect from something at 1.000sg.

Can someone help explain what is going on here?

Answer 1

Refractometers become less accurate once the yeast has started fermenting the sugars into alcohol. It fails to take into account that there is sugar, alcohol, and water in solution, and only measures the sugar and water. That is why you got a different reading. Ending at 1.000 isn't uncommon if you ferment to tolerance, but from what you've said, it sounds like you simply have a stalled ferment.