Secondary Headspace questions

[Ninkasi70]

I'm trying to get my brain wrapped around the hazards of too much headspace during time in secondary. I did a search and have been reading a lot of the old threads.

Q1: What's the problem with headspace?
It seems like the reason to avoid excess headspace is to avoid oxidation.
Is this simply the risk of ending up with cider/wine that has a "slice of cut apple that turned brown" flavor? Or is there something beyond that?

Q2: Why does adding more juice not cause a problem?
For the solutions. It seems like one answer is topping off with fresh juice. Doesn't this restart fermentation, and how does it not destroy your target sugar levels?

Q3: Would Nitrogen work as well as CO2?
The second solution is to lay down a layer of CO2. I found the picture of the gadget CvilleKevin uses to sink CO2 into his carboys. I don't have one of those, but I do have one of those whipped cream makers that takes the same kind of cartridges.

Nitrous Oxide (N2O) is inert, so why wouldn't I use the nitrogen?

I'm curious because I only have buckets at this point, so any thing that sits in secondary is going to have a bit of headspace until I decide what I'm going to do about carboys.

Thanks for any ideas you might have about this topic.

 

[Schnitzengiggle]

I'm trying to get my brain wrapped around the hazards of too much headspace during time in secondary. I did a search and have been reading a lot of the old threads.

Q1: What's the problem with headspace?
It seems like the reason to avoid excess headspace is to avoid oxidation.
Is this simply the risk of ending up with cider/wine that has a "slice of cut apple that turned brown" flavor? Or is there something beyond that?

Q2: Why does adding more juice not cause a problem?
For the solutions. It seems like one answer is topping off with fresh juice. Doesn't this restart fermentation, and how does it not destroy your target sugar levels?

Q3: Would Nitrogen work as well as CO2?
The second solution is to lay down a layer of CO2. I found the picture of the gadget CvilleKevin uses to sink CO2 into his carboys. I don't have one of those, but I do have one of those whipped cream makers that takes the same kind of cartridges.

Nitrous Oxide (N2O) is inert, so why wouldn't I use the nitrogen?

I'm curious because I only have buckets at this point, so any thing that sits in secondary is going to have a bit of headspace until I decide what I'm going to do about carboys.

Thanks for any ideas you might have about this topic.

1. For what it is worth, yes the goal is to prevent oxidation by minimizing headspace.

2. Restarting fermentation will produce more co2 thus protecting from oxidation. Some people backsweeten when adding juice, yes it will change your SG.

3. Nitrogen is actually lighter than oxygen (before oxygen on the periodic table) so I'm not certain that it would provide the protection against oxidation.

co2 being heavier than o2 will force the o2 out of the headspace as it consumes the volume, since N is lighter than o2, I don't think it would work without pressure.

Don't know if I am exactly right about the Nitrogen, but you are on the right track.

 

[dinnerstick]

1. are you sure nitrous oxide is inert?
2. let's not confuse nitrogen gas N2 with nitrous oxide N2O. furthermore the periodic table tells us nothing about density of gasses.
if it is really inert (make sure it does not act as an oxidizer- i have no idea!) and heavier than air (which is around 80% nitrogen gas N2) then why not? but then why not just get the right size carboy or just add some juice??
for topping off with juice, i generally need to add something like 500 ml or 1 liter of new juice after racking a 12 or 25 liter carboy. this doesn't get too much fermentation going, and doesn't really change sugar levels. if the juice is the same gravity as the original juice then it doesn't change anything at all.

 

[Ninkasi70]

Hmmm. Good question! (runs off to ask Mr. Google).

In the US, N2O is used as a food grade propellant for whipped cream in a can. According to Wikipedia, it's considered inert until you get to really high temperatures where it's used as an oxidizer in motorcar racing.

So far, I think I'm safe.

I really can't afford to buy stuff, and I don't have space to store it anyhow, so if I can use things I already have, that's perfect.

I already have the tools for dropping N2O into a sealable bucket. If there's some awesome reason why CO2 is better than N2O I'll go get some cartridges and see if they fit my dispenser. Otherwise, I want to use what I have.

So then the next question would be, how do you know when you've laid down enough gas to displace all the regular air?

 

[pistolpete]

In the US, N2O is used as a food grade propellant for whipped cream in a can. According to Wikipedia, it's considered inert until you get to really high temperatures where it's used as an oxidizer in motorcar racing.

The thing that would worry me is that at the high temperatures it is used as an oxidizer. It doesnt say that at low temperatures it doesnt cause oxidization at all, just that it is used as a propellant for things such as whipped cream... If it were me I'd see if CO2 canisters fit you application before jumping into the N20.

 

[Ninkasi70]

Well, I needed the smaller bottles that one of the Twins were crashing in, so I dumped that batch back to a sanitized fermentation bucket, topped off with enough fresh juice to bring the SG back up to about 1.002, squirted in a whole charger of Nitrous, popped on an airlock, and shoved the whole thing back into the fermentation cubby to sit for a while.

It wasn't clearing after a week in the fridge, so who knows what's going on. I figure that since it hadn't cleared, fermentation may restart to get rid of the added sugar, or if the yeast starved to death, the Nitrous will keep it from oxidizing (it is heavier than air after all). Either way, it can sit in a cool, dark place until it decides what it want to do with itself.