In the past, I only ever did top fermenting styles. I had to depressurise my bottles sometimes even more than once (using swing top bottles, luckily, this is not too awful). Now I made a Vienna Lager and even though I can‘t even really cold crash the bottles (I have them sit outside at maybe 10°C instead due to a lack in fridge space), my secondary fermentation is way slower than I’m used to. Is that to be expected?
With ales, I opened the bottles the day after starting secondary, and it sometimes was a deafening bang already. Now, I waited maybe even two days and haven‘t got more than a shy little pop.
I used powdered sugar (mixed with sterile water 1:1) to feed the yeast in secondary fermentation because I didn‘t have anything else in the house when I found the time to bottle. Is that maybe an issue?
Tldr of this measurement is that density is affected only negligibly (with low concentration of alcohol). Refractive index changes a lot.
These numbers were “discovered” by trying, maybe from some 15 yo Czech seminar my dad attended when he started. I just know that it works.
For sugar I am adding the least amount possible- it has some already ~3.5 °Bx and I don’t want bombs.