Danner
New Member
Hoping someone has some very specific scientific expertise to contribute to this question. Not really looking to get people's theories, as we have plenty of those already. Looking for a solid answer with objective evidence to support it.
The situation: several people each brewed 5 gallon batches of a Flanders Red ale with approximate average OG of 1.065. One batch was fermented with bugs from several commercial sour beers (involving pedio, lacto, brett) and the others were primaried with one of a couple strains of Saccharomyces. All the batches went into a full size used pinot noir barrel (fresh from having wine in it).
The beer aged in the barrel for 15 months. The final gravity of the beer racked out of the barrel was 1.008. We lost several gallons of volume to evaporation; exact volume lost is unknown.
What we're trying to figure out is what our ABV is. One theory is that most of what evaporated was H2O, so the solution was concentrated, so the amount of sugars eaten by the bugs may be greater than what the FG indicates, so perhaps the ABV is greater than the 7.8% suggested by gravity readings.
Or, was most of the evaporation in the form of ethanol, so is the ABV lower?
Then there's the matter of the wine still soaked in the staves of the barrel. Should we assume that added any measurable amount of alcohol to the beer, or would that somehow already be factored into the measured final gravity?
I'm no chemist and these matters are above my pay grade. The beer is really, really good though. We're just curious.
The situation: several people each brewed 5 gallon batches of a Flanders Red ale with approximate average OG of 1.065. One batch was fermented with bugs from several commercial sour beers (involving pedio, lacto, brett) and the others were primaried with one of a couple strains of Saccharomyces. All the batches went into a full size used pinot noir barrel (fresh from having wine in it).
The beer aged in the barrel for 15 months. The final gravity of the beer racked out of the barrel was 1.008. We lost several gallons of volume to evaporation; exact volume lost is unknown.
What we're trying to figure out is what our ABV is. One theory is that most of what evaporated was H2O, so the solution was concentrated, so the amount of sugars eaten by the bugs may be greater than what the FG indicates, so perhaps the ABV is greater than the 7.8% suggested by gravity readings.
Or, was most of the evaporation in the form of ethanol, so is the ABV lower?
Then there's the matter of the wine still soaked in the staves of the barrel. Should we assume that added any measurable amount of alcohol to the beer, or would that somehow already be factored into the measured final gravity?
I'm no chemist and these matters are above my pay grade. The beer is really, really good though. We're just curious.
