Question for all of you brewers, not long ago me and some buddies made a batch of IPA. After allowing it to ferment for about 2 weeks and confirming fermentation was completed with a hydrometer, we split the batch into two secondary vessels for dry hopping and added 5 lbs of bosc pears to half of the batch. There was very minimal additional fermentation that occurred in the beer with pear, and we left both fermentation vessels sitting in the same exact conditions in order to complete secondary fermentation/dry hopping for another 7 days prior to bottling. There was no additional appreciable hydrometer reading difference in the beers before bottling. We opened the beers after about 3 weeks of being in the bottle and the plain IPA looked great, poured great, tasted great. The beer with bosc pears in upon opening would fizz out about 2/3 of the bottle contents immediately upon opening. I'm a bit at a loss here with exactly what went wrong. Same fermentation conditions, confirmed fermentation was complete after bottling, yeast used was WLP001, same priming solution with the same amounts added to each part of the split batch, same serving temps.... Any suggestions? I have used fruit in many of my IPAs and never had an issue until now. Thanks!
I suspect either an infection introduced with the pears or the pears added some sugars that didn't get a chance to ferment out before you bottled. How did you prepare the pears before adding them to secondary?
It is possible that you did not reach FG with the pear beer. That is most likely. But some other things could have happened, or some combination of the following. The pear beer has bits of fruit, those bits can detach from the bottom and will grab CO2 as it rises. Not unlike stirring a carbonated beverage. Contamination. If your pear was carrying any wild bacteria it will go to town on otherwise unfermentable sugar. Keep them cold! Cheers.
Wild yeast from the pears began fermenting the complex carbohydrates that beer yeast do not metabolize thus increasing carbonation beyond what the beer yeast would have achieved on their own with the priming sugar.
Very interesting billandsuz, I was not aware of this. I know that when I have a beer with fruit or other sediment on the bottom I typically try to handle with care so as not to shake it all up, I don't think my friend realized this and he was the one pretty much handling the bottles prior to open. We peeled and cored the pears, then cooked them down in a pot and mashed them, like a chunky pear sauce, let them reach boiling and simmered for a while, then placed them in a sanitized nylon mesh bag with the hops and threw em in. You could be right though about an infection or the sugars, those were my thoughts. I should probably look a bit more into what types of sugars that type of pear has to see if some of them are not as easily and quickly fermented.
As a yearly cider make, I can say for certain that bottled home made cider can be unpredictable. It is sometimes difficult to get a clear pour with bottle conditioned cider, the debris just floats up like crazy and can really cause fizzing if not outright gushing. But if you get the beer very cold it will help a bit. That and of course be gentle. Good luck. Cheers.
It's not the sugars present in the pears, not usually. That will be mostly fructose. The wild bacteria that resides on the pears, those bugs will eat many complex sugars that brewers yeast will not. Slowly. So the primary yeast may have finished and left behind unfermentable, but the unfermentable is great food for wild yeast, and they will consume those sugars and produce CO2. They are only unfermentable to brewers yeast, and that is sort of why we call anything else wild. Another term is that brewers yeast are domesticated, they do what we want, they work for us, usually. Not so with wild yeast. Assholes. Since you boiled the pears, this is less likely. But still possible. Cheers.
If you are going to boil the pears you might as well use table sugar. Very little pear flavor/aromatics will make it through the boil. You might try using a pear concentrate/puree at high Krausen or even pear juice if you adjust your recipe for more mouthfeel. Another idea is to use a yeast with pear-like esters (eg. WLP-023). Cheers
Agree, almost certainly a microbe or yeast off the pears. Especially since that was the only variable.
I really didn't taste any tartness in the pear version beyond the hops used, although I know that I really shouldn't have received much in the way of taste or nose after I boiled the pear, the taste was very pleasant in "what was left of" the beer. It was a mild flavor and there was only mild pear essence in the nose, but no added tartness.
That could tend to rule out an infection, although I don't know how quickly a tartness would show up if it were infected. I think some re-fermentation from the pears after bottling would be the leading reason for the over-carbonation. However, something else to consider is that you could also have inconsistent carbonation from not mixing the priming sugar well enough to distribute it evenly between bottles. If you have some bottles with minimal or no carbonation, and some with too much carbonation, then there's your reason. Possibly you selected one of the bottles that has too much priming sugar. Are you confident that the priming sugar was well mixed in the bottling bucket?
I rack my beer in a fashion over the priming sugar so that it gets pretty mixed in while not adding unnecessary oxygen and we have since opened several other bottles all with similar results, but a good thought! Cheers!
Thanks all for the very helpful suggestions and insights into the possible problems with this beer. I am sure it likely was just a delayed fermentation brought on by the pear addition that did not develop and ease enough in secondary, or that it was an infection/wild yeast strain which caused this additional fermentation. Thankfully no bottle bombs yet, just some foamy beer wasted. Live and learn I guess. Thanks!
