MOLEY PLEASE READ

[BrightBrew]

Moley, in some other posts you mentioned keeping a small amount of water and some crushed campden tablets in your demijohns and occasionally giving it a shake to keep it nice and clean.

So I thought this was a great idea and after bottling some cider at the weekend I did as you said, however, when I gave it a shake earlier today there was a very eggy smell, even through the foil on top!!

Any ideas what the eggy smell is? :sick: (obviously given the smell i'm going to sanitise fully before using again - just wonder what the smell is).

 

[Moley]

Campden tablets or sodium/potassium metabisulphite + water releases sulphur dioxide.

Rotten eggs = sulphur dioxide.

Some fermenting juices, especially apple, can give off sulphurous smells.

Just because it smells of sulphur doesn't necessarily mean that anything's rotten.

 

[BrightBrew]

:grin: Phew, that's good then. Thought I'd maybe left some nasties festering away.

Cheers Moley, informative as ever :thumb:

 

[shocker]

Im not Moley nor anything like as good, but I can second the eggy cider thing .I have one on the go just now that is giving off a hint of the old sulphur di . I too got a little upset but got reassured here and cast my mind back.....

Back along when we used to buy cider by the gallon from the corner shop the best barrels always smelt slightly eggy .Pilot Richards ,near bristol , his cider was the best ever and that had an egg tinge to it .If you dont lose the tint during its condition and mature phase then a slice of lemon wedged on the rim of the glass was the prescribed medicine .

Now if you was to smell vinegar too ,a kind of pickled egg scent ,well ,THEN you may start to worry ! :sick:

 

[Moley]

Now if you was to smell vinegar too, a kind of pickled egg scent, well THEN you may start to worry!

Not necessarily, it depends on what you're brewing, I don't make cider and I've never noticed it in wine but I have been concerned about slight vinegary smells from working beers, and then it has gone away again and everything has turned out right.

Let's see if I can simplify the science:

Molecules are made up of atoms.

Atoms have different numbers of bonds, let's think of them as hands.

A Hydrogen atom only has one hand, it will hold hands with another Hydrogen to form hydrogen gas but that's unstable and it would rather hold hands with something else.

An Oxygen atom has two hands. It will quite happily hold both hands with another Oxygen to form the oxygen gas in the air we breathe. It will also hold hands with two Hydrogens and make a water molecule. It will hold two hands with a Carbon but would prefer to hold one Carbon and one Hydrogen.

A Carbon atom has four hands. It will hold hands with four Hydrogens to make Methane gas or two Oxygens to make Carbon Dioxide. If one Carbon holds three Hydrogens and one Oxygen, while the Oxygen grabs a Hydrogen with its other hand, that's Methanol, and we don't want that.

What we want is one Carbon holding three Hydrogens and another Carbon, with that second Carbon also holding two Hydrogens and one Oxygen, while that Oxygen grabs another Hydrogen - that's Ethanol alcohol.

If we give a Yeast cell a Sucrose molecule (that's your common granulated sugar, which has 12 Carbons all holding hands with each-other and a bunch of Hydrogens and Oxygens) the first thing it does is snap it in half and mix in another Water molecule to make two 6-Carbon sugars, Glucose and Fructose, which both have the same number of friends but are arranged slightly differently.

So a Glucose molecule (that's your brewing sugar) has six Carbons, twelve Hydrogens and six Oxygens. The yeast cell is programmed to break that up and make two Ethanols and two Carbon Dioxides.

While the yeasts are frantically trying to smash up all of these sugars and put together Ethanols and Carbon Dioxides, sometimes they get it wrong. So you've got two Carbons together, one's holding three Hydrogens but the other has got one Hydrogen and two Oxygens instead of two Hydrogens and one Oxygen. But hey, there's so much to do and so little time, let it go for now. That one that's wrong is an Aldehyde and will have a vinegary smell.

Later in the day, when the rush has died down, the yeasts will look around for their earlier cock-ups and put them right. This is why we keep on saying that you should give them proper time to finish their job and do all of the clearing up.

 

[BarnsleyBrewer]

Phew, glad that's cleared up. LoL :clap:

BB :thumb:

 

[ingypingy2]

Now if you was to smell vinegar too, a kind of pickled egg scent, well THEN you may start to worry!

Not necessarily, it depends on what you're brewing, I don't make cider and I've never noticed it in wine but I have been concerned about slight vinegary smells from working beers, and then it has gone away again and everything has turned out right.

Let's see if I can simplify the science:

Molecules are made up of atoms.

Atoms have different numbers of bonds, let's think of them as hands.

A Hydrogen atom only has one hand, it will hold hands with another Hydrogen to form hydrogen gas but that's unstable and it would rather hold hands with something else.

An Oxygen atom has two hands. It will quite happily hold both hands with another Oxygen to form the oxygen gas in the air we breathe. It will also hold hands with two Hydrogens and make a water molecule. It will hold two hands with a Carbon but would prefer to hold one Carbon and one Hydrogen.

A Carbon atom has four hands. It will hold hands with four Hydrogens to make Methane gas or two Oxygens to make Carbon Dioxide. If one Carbon holds three Hydrogens and one Oxygen, while the Oxygen grabs a Hydrogen with its other hand, that's Methanol, and we don't want that.

What we want is one Carbon holding three Hydrogens and another Carbon, with that second Carbon also holding two Hydrogens and one Oxygen, while that Oxygen grabs another Hydrogen - that's Ethanol alcohol.

If we give a Yeast cell a Sucrose molecule (that's your common granulated sugar, which has 12 Carbons all holding hands with each-other and a bunch of Hydrogens and Oxygens) the first thing it does is snap it in half and mix in another Water molecule to make two 6-Carbon sugars, Glucose and Fructose, which both have the same number of friends but are arranged slightly differently.

So a Glucose molecule (that's your brewing sugar) has six Carbons, twelve Hydrogens and six Oxygens. The yeast cell is programmed to break that up and make two Ethanols and two Carbon Dioxides.

While the yeasts are frantically trying to smash up all of these sugars and put together Ethanols and Carbon Dioxides, sometimes they get it wrong. So you've got two Carbons together, one's holding three Hydrogens but the other has got one Hydrogen and two Oxygens instead of two Hydrogens and one Oxygen. But hey, there's so much to do and so little time, let it go for now. That one that's wrong is an Aldehyde and will have a vinegary smell.

Later in the day, when the rush has died down, the yeasts will look around for their earlier cock-ups and put them right. This is why we keep on saying that you should give them proper time to finish their job and do all of the clearing up.

I wish you'd been my science teacher Moley lol!! :) It all makes perfect sense when you word it like that lol!! :)

 

[shocker]

I was only joking about the pickled eggs......

.... I'll get my coat then,......

 

[wino2012]

:shock:

 

[BarnsleyBrewer]

Whoooo, old post.... :?

 

[PD]

What a friendly happy world our little friends live in.... :clap: :clap: