In Keg Natural Carbonation and Conditioning

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I thoroughly dislike yeast in bottles !, well its more disturbing sediment when pouring I dislike.

But I do like the subtle difference between bottle conditioned and force carbonated beer .
Subjective I know, and Im sure someone will pop up and tell me I just imagine it, but I do think there is a difference.

My plan is to throw in some Sugar and carbonate / condition my next batch in the keg with a floating tube. In theory if I need to later bottle some I will be bottling cask conditioned without sediment.

However the EweToob educational vids on the matter throw up more questions than answers.

1- They all advocate boiling the priming sugar in water before dropping it in a sanitised keg.. my question is Why? Surely using boiling water out the of a kettle will sanitise everything. Or is this a step that they use in the USA cause they dont, in general, have tea kettles .?

2- They all advocate purging the keg with Co2 almost as if it was a closed transfer. is this oxygen avoidance so critical when feeding the yeast with priming sugar should have them scavenging oxygen . or am I missing something ?

3- One ewetoober said to use a lower ratio of priming sugars when kegging lest it froth muchly..
surely a carbonation ratio of say.. 2.2 is the same whether its to prime 19L or 500ml. The online calculators give a quantity of priming sugars for batch priming.. I cant understand why it would produce any greater volume of Co2 whether its stored in a bottle or a keg.. or am I wrong

Whats the collective opinion ? ( lights blue touch paper and stands back )
 
You aren't alone in recognising natural conditioning gives a better mouthfeel than forced carbonation.

1) If there are any spoiling bacteria around the home they will be in the kitchen, especially sugar. I just simmer mine for about 5 minutes.
2) Purging the keg with CO2 would take a lot of CO2. There is a chart on line about what pressure to purge and how many times. No foam sanitiser with water and push it out of the keg a lot of info online on how to do it. Once yeast switches from aerobic respiration to anaerobic respiration it doesn't need to take up oxygen again.
3) Rule of thumb is half the amount needed when batch priming, I have never bothered to find out why because you can put more in and vent any oxygen out of the keg

A bit of a read here from a home brewer who is also a microbiologist. He is also a lawyer so don't write to him.😅
https://www.morebeer.com/category/wort-oxygenation-aeration.html/#Biochemistry of yeast
 
1. Possibly just being thorough, but I hadn't thought about people in the US and their lack of kettles! It's almost certainly entirely that. Without a kettle, you'll need a pan to heat the water in so you may as well boil it with the sugar in. Obviously, for us with kettles, we don't want to put sugar in the kettle.

Boiling water will flash pasteurise the sugar. But that's probably unnecessary anyway because most things can't live on pure sugar (osmotic forces etc) which is why sugar doesn't go mouldy/off when sat in a cupboard for years. Plus, the low pH and alcohol in the beer will pretty much kill of anything else anyway. Most people don't take and special measure when bottle priming with table sugar. Same happens if you were to keg prime.

2. You're right in that it's not as important to worry oxygen if you're priming the keg. As with bottle conditioning, the yeast will take in the excess oxygen as they metabolise the sugar during the refermentation. But apparently whilst it'll scavenge most of the oxygen, it won't scavenge all of it. There are a lot of myths around, so this is where I would defer to someone like DocAnna who's studied this stuff. Additionally, even though the yeast is scavenging the oxygen, it doesn't do it immediately and the beer can begin to stale in very short amounts of time (30 mins).

In short, like bottle conditioning, the yeast will harvest most of the oxygen, but it's not a magic bullet. Purging with co2 is probably still important, but not as important as if you don't prime and all that oxygen just sits in the keg.

3. I'm unsure. Maybe something to do with relative headspace? As you say, it's just ratios.
 
Peebee has answered the question correctly before, in the presence of oxygen yeast will go into the Krebs cycle and produce acetaldehyde. Brewing yeast both Saccharomyces cerevisiae (ale yeast) and S. pastorianus (lager yeast) are unique in the fact that they will both in the presence of both sugar and oxygen, ferments sugars even though aerobic respiration produces far more energy than anaerobic fermentation. Other yeast strains will make alcohol in the presence of oxygen and then start to consume the alcohol. (The Krebs Cycle)
I am not saying brewers yeast won't do this they will in the presence of oxygen. That is why it is important to reduce the risk of oxygen uptake.
https://www.thehomebrewforum.co.uk/threads/low-alcohol-brewing-with-aerobic-fermentation.97409/https://beersmith.com/blog/2015/06/18/why-oxygen-is-bad-in-your-home-brewed-beer/
 
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Peebee has answered the question correctly before, in the presence of oxygen yeast will go into the Krebs cycle and produce acetaldehyde. Brewing yeast both Saccharomyces cerevisiae (ale yeast) and S. pastorianus (lager yeast) are unique in the fact that they will both in the presence of both sugar and oxygen, ferments sugars even though aerobic respiration produces far more energy than anaerobic fermentation. Other yeast strains will make alcohol in the presence of oxygen and then start to consume the alcohol. (The Krebs Cycle)
I am not saying brewers yeast won't do this they will in the presence of oxygen. That is why it is important to reduce the risk of oxygen uptake.
https://www.thehomebrewforum.co.uk/threads/low-alcohol-brewing-with-aerobic-fermentation.97409/https://beersmith.com/blog/2015/06/18/why-oxygen-is-bad-in-your-home-brewed-beer/
Excellent Ill follow the science and stick with closed transfer when kegging dont want the Crabtree effect anywhere near my precious beer
 
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I thoroughly dislike yeast in bottles !, well its more disturbing sediment when pouring I dislike.

But I do like the subtle difference between bottle conditioned and force carbonated beer .
Subjective I know, and Im sure someone will pop up and tell me I just imagine it, but I do think there is a difference.

My plan is to throw in some Sugar and carbonate / condition my next batch in the keg with a floating tube. In theory if I need to later bottle some I will be bottling cask conditioned without sediment.

However the EweToob educational vids on the matter throw up more questions than answers.

1- They all advocate boiling the priming sugar in water before dropping it in a sanitised keg.. my question is Why? Surely using boiling water out the of a kettle will sanitise everything. Or is this a step that they use in the USA cause they dont, in general, have tea kettles .?

2- They all advocate purging the keg with Co2 almost as if it was a closed transfer. is this oxygen avoidance so critical when feeding the yeast with priming sugar should have them scavenging oxygen . or am I missing something ?

3- One ewetoober said to use a lower ratio of priming sugars when kegging lest it froth muchly..
surely a carbonation ratio of say.. 2.2 is the same whether its to prime 19L or 500ml. The online calculators give a quantity of priming sugars for batch priming.. I cant understand why it would produce any greater volume of Co2 whether its stored in a bottle or a keg.. or am I wrong

Whats the collective opinion ? ( lights blue touch paper and stands back )

I agree about mouthfeel, and so do millions of champagne drinkers.
IMO
1. Bleachqueenery
2. Unless they are purging with dry ice or a fogger. This is only making them feel better.
3. Technically maybee, but actually the square root of a sparrows fart.

You can also sharpen your clearing / Fining techniques and bottle stunningly bright beer.

Secret santa sent me some smashing bright beers. Which made me think too. At the end of the day its 'input time' vs 'clarity' for 99% of the beer which I drink myself.

You can also choose your yeasts carefully.
They can be right little floccers😁
 
I tried this once and it wasn’t successful. I think it was because I had too much headspace in the keg so pressure didn’t build sufficiently to carbonate the beer so maybe minimise headspace. Gas is compressible and liquid isn’t so if you have a lot of headspace the amount of additional volume of co2 needed to compress that headspace sufficiently to push co2 into the beer is exponential. So I’d go for something like a quarter litre of headspace or less next time.
 
Would this be a good job for a spunding valve set at the apropriate pressure for conditioning temp?
Yes, you could increase the sugar amount and let the resulting CO2 scrub any oxygen from the keg. You are eventually going to attach a gas bottle to force the beer out but I don't know if that affects the mechanics of the dissolved CO2 from your keg conditioning.
 
I'm guessing the bottle conditioning calculators out there assume some level of headspace that is typical of what you would normally find in a bottle and therefore some level of fermentation activity in the bottle which is a closed space. Without a calculator to take into account the volume of headspace you're guessing - maybe as a first order assumtions you can take the number of bottles worth of beer and make sure you have headspace equivalent to that number of bottles worth of headspace. If you have more headspace in your keg then increase the amount of priming sugar and if you have less decrease the amount of priming sugar. I've never thought of using a spunding valve, I guess it could work in principle if you could establish what target pressure you need to shoot for in order to achieve the right level of carbonation....I would expect that the pressure in the headspace in a bottle will be alot higher than normal carb pressure initially, then reduce as the beer absorbs CO2, so you'd need to set your spunding valve for a higher pressure than your target carbonation pressure.

Might be easier and less faff to just convert your keg into a pressure fermenter and ferment under pressure to achieve natural carbonation.
 
Might be easier and less faff to just convert your keg into a pressure fermenter and ferment under pressure to achieve natural carbonation.
I did think that and its fine for lagers and all things hoppy, however for ales and darker beer pressure fermentation isnt overy forgiving. So I have ordered a 0-30psi spunding valve to let me over prime the Keg, and let the spunding valve vent priming down to the relevant pressure e.g 18C co2 volume 2.0 set spund valve at 16psi
I'm guessing the bottle conditioning calculators out there assume some level of headspace that is typical of what you would normally find in a bottle and therefore some level of fermentation activity in the bottle which is a closed space
i was thinking along those lines this morning that the accumulated headspace in 40 odd bottles will be considerable less than the half Litre, or less, left in a keg..
 
I thoroughly dislike yeast in bottles !, well its more disturbing sediment when pouring I dislike.
Does this apply to all bottle conditioned beer? When done well with the right yeast as with something like St. Austell Proper Job, there's very little to nothing, that comes off the bottom of the bottle. Filtering or fining, then dosing with the correct quantity of a dedicated bottling yeast might solve this issue, whilst still maintaining the benefit of refermentation in the bottle.
 
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Does this apply to all bottle conditioned beer? When done well with the right yeast as with something like St. Austell Proper Job, there's very little to nothing, that comes off the bottom of the bottle. Filtering or fining, then dosing with the correct quantity of a dedicated bottling yeast might solve this issue, whilst still maintaining the benefit of refermentation in the bottle.
Pretty much anything that still has detectable yeast in the bottle is on my black list.. i like my beer either as clear as possible. or blacker than darkness
 
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Well a bottled beer can be crystal clear and bottle conditioned...just don't shake the bottle before opening, give it time for the yeast to settle out to the bottom of the bottle and pour carefully so not to let the 'sediment' at the bottom to slip out into the beer. Its not Orangina :laugh8:
 
Well a bottled beer can be crystal clear and bottle conditioned...just don't shake the bottle before opening, give it time for the yeast to settle out to the bottom of the bottle and pour carefully so not to let the 'sediment' at the bottom to slip out into the beer. Its not Orangina :laugh8:
👍
And depending on what yeast you use, it can stick to the bottle like glue. I used to be able to up-end a bottle that had been fermented with S-04 and it would come out crystal clear.
 
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