Looks like infection before even pitching yeast

[Tallgrass]

In my 105 year old basement my hydrometer sample, from the kettle, always seem to spontaneously ferment after a few days. Smells sour and I haven't had the courage to taste it.

 

[Miraculix]

In my 105 year old basement my hydrometer sample, from the kettle, always seem to spontaneously ferment after a few days. Smells sour and I haven't had the courage to taste it.

Try! Sounds promising!

Or invite @RPh_Guy

 

[RPh_Guy]

An open wild fermentation like that probably wouldn't taste good.

• Most wild yeast doesn't attenuate wort very well, so it would be too sweet.
• It would be oxidized.
• Oxygen suppresses yeast esters.
• Bacteria off-flavors are likely present (e.g. isovaleric, butyric, and acetic acids).
• Most of the greatness of spontaneous fermentation comes from Brettanomyces, which is unlikely to be present.

You could try it though if you want. It's likely to be safe if there's no mold.

Why is a hydrometer sample sitting around for days?

 

[Tallgrass]

Why is a hydrometer sample sitting around for days?

First time was an accident. After that curiosity.

The 10 or so times it's happened they all smell the same. I once left it a couple weeks and it only got down to 20 from 50. I think my experimenting is over.