Does Freezing Fruit Sterilize It?

[Delaney]

Hey,

I have been picking tons of raspberries for wine as well as beer. I washed most of my raspberries before freezing, but I am sure there is the odd insect, or moldy raspberry. Some weren't washed before freezing, but I'm quit certain they are organic...I picked very selectively but sometimes things fall into your basket...I found a few tiny worms on some, I assume they'll die off in the alcohol? (The berries have been frozen for two weeks on average)

Would freezing kill mold and bacteria that pose contamination risks, or would I still want to steep the berries at 170F?

 

[bjl110]

Freezing does not sanitize anything. It just slows the bacteria down. If you want to be sure, you have to cook it. Having said that many people on hbt seem to have had good results adding frozen fruit straight to the secondary. I can't speak to "beer knowledge" but my cooking knowledge says no.

 

[nordoe]

It does not, but it will break down the cell walls to make it easier to transfer taste.

 

[inkman15]

+1 on the above responses regarding sterilization. I just did a blackberry beer myself (currently in the secondary) and I used store-bought fruit that I froze and put directly in the secondary. There seems to be a bunch of different opinions on how to use fruit (freeze it, puree it, do nothing to it, etc...) but based on the threads I've read here, people seem to have good results just freezing it and adding to secondary. Check out these threads:

https://www.homebrewtalk.com/f39/adding-strawberries-2ndary-106243/
https://www.homebrewtalk.com/f39/adding-blackberries-secondary-134322/
https://www.homebrewtalk.com/f39/sanitizing-fruit-other-alternatives-253994/

 

[Ckarsanac]

+1 on "No" to sterilization. It stops them "cold" (see what I did there :cross, but it doesn't kill them.

However, if you're using fruit in the secondary, the yeast have made the wort/near-beer pretty inhospitable to most other micro-organisms. I think using frozen store bought fruit is fine in secondary. I would be more worried about fresh fruit into secondary... JMO though...

 

[Delaney]

Mine are fresh, but I've been quite sanitary...I think it should be okay.

I have a bottle of pasteurized honey that I opened and used when brewing the wort. I steeped what I used then at 155F for 10 minutes.

Can I just add the honey straight up into the secondary fermenter, or should it be sterilized? If it should be sterilized, how little water can be used to steep say a pound of honey?

 

[Ckarsanac]

I would add the honey directly. It is WAY more sterile than the fruit. Plus, if you read the mead forums, heating the honey will destory some of the aromatics.

 

[Delaney]

I would add the honey directly. It is WAY more sterile than the fruit. Plus, if you read the mead forums, heating the honey will destory some of the aromatics.

from what I;ve read, not between 140-160F

 

[Ckarsanac]

Where did you read that? Just curious...

http://www.amazon.com/dp/0937381802/?tag=skimlinks_replacement-20


Ken doesn't heat any of his honey for that reason. But, we may be splitting hairs here. Any aromatics would probably be overpowered by the hops/malts/rapberry flavors anyway.

 

[Delaney]

Yeah well...I just heated mine to 140F...then dumped it straight into wort without cooling and stirred it...I think it'll be fine. I've read in several places on brewing forums that under 150F you retain most of the aroma/flavour and kill bacteria.

 

[bjl110]

Using honey will only give you minimal (if any) honey flavor if used in the boil. Mostly it will just up the ABV and dry it out. If you want the flavor or aroma of honey, consider honey malt. Mead is pretty much all honey and doesn't really taste "like" honey. There certainly are characteristics that are in line with honey, maybe "reminiscent of", but not full honey flavor and aroma.

Edit: Just saw that you were adding it to the secondary, not the boil. Ignore me . Let us know how that works for you. I was going to use honey malt for a beer that I wanted a touch of honey in, but would probably do the secondary thing if it works out for you well.

 

[bluemoose]

Hey,

I have been picking tons of raspberries for wine as well as beer. I washed most of my raspberries before freezing, but I am sure there is the odd insect, or moldy raspberry. Some weren't washed before freezing, but I'm quit certain they are organic...I picked very selectively but sometimes things fall into your basket...I found a few tiny worms on some, I assume they'll die off in the alcohol? (The berries have been frozen for two weeks on average)

Would freezing kill mold and bacteria that pose contamination risks, or would I still want to steep the berries at 170F?

If you are worried, use Campden tablets to sanitize the fruit.

 

[Delaney]

If you are worried, use Campden tablets to sanitize the fruit.

so I would drop the campden tablet into the wort?...or dissolve the tablets into a solution, which I'd pass through the fruit to serilize them?

I actually added the honey to primary but after 3 days, so the OG went from 1.042 down to 1.014 during teh 3 days in primary before I added the honey. The honey was added to the primary though. Secondary is a few days off at least

 

[bluemoose]

so I would drop the campden tablet into the wort?...or dissolve the tablets into a solution, which I'd pass through the fruit to serilize them?

I actually added the honey to primary but after 3 days, so the OG went from 1.042 down to 1.014 during teh 3 days in primary before I added the honey. The honey was added to the primary though. Secondary is a few days off at least

Don't drop into the wort. Crush them in water and add the fruit. Let them soak in the fridge for 24 hours. It should kill all the wild yeasties and bacteria.

Here is a link to a thread that Yooper has responded to. This is where I got the idea of Campden Tablets. I ended up using vodka, but this might work better for you.

https://www.homebrewtalk.com/f14/sumac-255637/index3.html

 

[GoHawks]

Im a noob so take what I have to say with a grain of salt

Freezing bacteria will kill some but not all of them. When you crystallize water (freeze water) inside a bacterium some of them will swell and pop due to the fact that crystallized water takes up more volume then just regular water.

Given that they are incredibly adaptable and strong little guys many bacteria will find a way to survive having what is equivalent to giving an alka seltzer tablet to a seagull (ive never done this btw).


I have a B.S. in microbiology which is why I replied with my answer.

 

[Yooper]

But fruit is literally covered with wild yeast, and that's the real risk.

 

[Delaney]

But fruit is literally covered with wild yeast, and that's the real risk.

Why is wild yeast a risk? If the wild yeast ferments as well as the yeast culture I've added, is there any other risk asides for the flavor being affected?

I've read that bringing the raspberries to 170F will kill off most unwanted bacteria/yeast...However this would be disadvantageous in terms of something to do with pectin that I do not understand.

Which method is less likely to produce negative effects?

 

[bluemoose]

Delaney,

Wild yeast are unpredictable in terms of flavor. Some might be great, others not so much. You want to try to control as many variables as possible when brewing. A good brewer doesn't just make a great batch, they can repeatedly make that great batch. I would suggest using the campden tablets.

Heating the fruit can release pectins that will cloud the beer. I'm not sure how much it will affect the fermentation process, but there is a pectin enzyme used for mine making that can help to clear it afterwards.

Bottom line is get rid of the yeast in 1 step. Campden tablets.

 

[SLBrooks]

So no using oxiclean then rinsing to clean the fruit and no letting it sit in sanitizer... bummer.

Are Iodine tablets off limits too?

Curious because I'm going to be making a peach ale in a few weeks.

 

[Delaney]

So no using oxiclean then rinsing to clean the fruit and no letting it sit in sanitizer... bummer.

Are Iodine tablets off limits too?

Curious because I'm going to be making a peach ale in a few weeks.

I think you need to apply common sense...if it's a no rinse sanitizer, then it should be good...

I'll go with the tablets and see how it turns out.

 

[ChshreCat]

If you're really sweating it about the fruit and don't have campden, you can always just give it a quick blanch in boiling water. That'll kill most/all of what's on the outside without cooking the betters (much).

 

[Delaney]

Damnit!

I think I messed it up.

I added 4 campden tablets to 6 pounds of berries.

6 pounds of berries will be used for 10 gallons of beer. My fruit turned white...I think it's too concentrated...

The tablets are needed at a rate of 1 per 2.5 gallons. I believe that I should have been calculating 1 tablet per 2.5 gallons of crushed fruit, instead of per 2.5 gallons of beer?

 

[bluemoose]

Don't drop into the wort. Crush them in water and add the fruit. Let them soak in the fridge for 24 hours. It should kill all the wild yeasties and bacteria.

Here is a link to a thread that Yooper has responded to. This is where I got the idea of Campden Tablets. I ended up using vodka, but this might work better for you.

https://www.homebrewtalk.com/f14/sumac-255637/index3.html

Hate to quote me, but check that thread post 23 and 25.

 

[MikeRoBrew1]

I ruined a batch by using frozen organic raspberries. It's your money but i would play it safe and be sure.