Welcome to the homeBBBrew board!
Like the BBB, the homeBBBrew board is not a club, just a place to talk about making beer. Is there a swap you would like to see happen? If we can find a few others who have something similar then lets do it!

I just really like the work levifunk is doing!

YOUR BBB USERNAME AND PASSWORD WILL NOT WORK ON THIS BOARD! If you want to post, you need to read this.

Brettanomyces Brewing
E-Symposium Transcript!

Trouble making Trappists?
Discover Liquid Candy Syrup!
See what color impact to expect from liquid candy.

Search for:
Author Replies
10/16/11 07:26 PM  
Using Fresh Fruit in sour beers
Are there any advantages to freezing fresh fruit before adding it to secondary? I would think fresh cut fruit would contribute to the complexity of the beer by introducing more wild yeast and bacteria. Is this true? Or am I risking off flavors by not freezing the fruit first. Thanks
10/17/11 02:17 PM  
Re: Using Fresh Fruit in sour beers
Both methods work. One of the advantages of freezing is that it breaks down the cell walls on the fruit.
10/17/11 03:09 PM  
Re: Using Fresh Fruit in sour beers
Why is it good to break down the cell walls? Does this help the fruit flavor assimilate into the beer?
Mike T
10/17/11 03:39 PM  
Re: Using Fresh Fruit in sour beers
Exactly, you want to give your little guys a path into the fruit passed the skin. They'll get there eventually by thawed or crushed fruit speeds up the process. I generally freeze just because it allows me to buy the best fruit cheap in the summer and then add it to beers in the winter when I generally have more time to brew.

Just put a gallon of two amber-ish beers onto sour cherries yesterday and thinking of brewing a sour dubbel in a few weeks that will eventually get plums.

10/19/11 12:01 PM  
Re: Using Fresh Fruit in sour beers
BTW, freezing the fruit (or anything) will have very minor effect on any microbes. The ones that are able to survive on the skin of fruits, will just go to sleep when frozen. i.e. freezing is not "desinfecting", it just temporary stops the activity when the microbes go into sleep mode. So you are not missing the bug contribution by freezing.
10/21/11 12:41 AM  
Re: Using Fresh Fruit in sour beers
With regards to using frozen fruit in beer...

We know that fresh fruit is covered with yeast can bacteria. But what happens when we freeze the fruit? From the limited research I've done, it seems that freezing yeast without the use of glycerol will cause the cell membrane to burst rendering it useless for brewing. It's possible not all yeast cells die under freezing temps, but the cells won't have the ability to eat and reproduce at a healthy rate. My feeling is this...with regards to using frozen fruit in beer, the wild yeast living on the fruit will have little effect on the fermentation or flavor of the beer.

Bacteria on the other hand are unicellular organisms and, as such, are much better equipped to deal with extremes of temperature. Many species of bacteria can form spores that are extremely resistant to temperature extremes, so I'd venture to say the flavor impact of frozen fruit in beer it's most likely from bacteria, not from the yeast.

10/21/11 10:28 AM  
Re: Using Fresh Fruit in sour beers
I think you're over-thinking this. That's not a criticism, I do it all the time too! I agree with Carl that freezing fruit will have very little impact on any microbes on the fruit skin. Once thawed, they just wake up and do their thing. To me, the advantage to freezing fruit is that I can purchase the fruit in season but brew later in the year. Also, breaking the cell walls allows the fruit juice to extract into the beer. Once I put fresh (unfrozen) raspberries in the secondary and pulled them out a couple months later and there was still juice trapped in the berries ... the cell walls hadn't dissolved in that time. So now I smash them up and freeze them, even if just overnight.

But all that being said, if you are doing a standard fermentation with store-bought yeast or a blend, then in my experience the impact from any additional fruit-borne wild yeast and bacteria is pretty minimal. A little complexity sure, but in my experience it doesn't drastically alter the beer. And whether that slight impact is from wild yeast vs. bacteria is anyone's guess, and probably depends on the specific location, the time of year, the temperature when harvested, etc. All that stuff impacts the type and extent of wild yeasts and bacteria. You could probably brew the same beer multiple times and each time get a slightly different impact from the wild microbes on the fruit. Slightly different, but mostly the same.

Return to Forum

Post a Reply
Your Name:
Message Body:



Around Bruges in 80 Beers: 2nd Edition

Around London in 80 Beers

Around Brussels in 80 Beers

Babblebelt contributors in attendance: