What Is Going On During The Brewing Process

[Verb77]

Hi all; I’m in the process of my first brew. Can anyone please explain what is actually going on during this process??

Its currently fermenting away at the moment, what does the yeast actually get up to during this and why does it rise to the top then settle down??

What does the sugar do also during this process and why do we add more to the bottle during bottling?? And what implication does reducing or increasing the amounts of sugar added make during both stages?? The same also goes with the quantity of water I use, i.e. too much or not enough??

I know I’ve asked a few questions here. But I find that if I understand what is actually going on then I stand a better chance of making the right improvements as I go along for future brews.

Thanks
Carl

 

[Wez]

There will be much more scientific explanations to your questions, but here are a few quick answers.

Hi all; I’m in the process of my first brew. Can anyone please explain what is actually going on during this process??

Its currently fermenting away at the moment, what does the yeast actually get up to during this and why does it rise to the top then settle down??

The yeast is feeding on the sugars and the by product from this process is Alcohol.

What does the sugar do also during this process and why do we add more to the bottle during bottling??

During this process the sugars (well the fermentable ones) are eaten by the yeast. The yeast gives off c02 during the fermentation stage, once all of the fermentable sugars are gone fermentation is considered to be over, but..you still have hungry yeast cells in suspension in the wort (thats why it's cloudy) when you add sugar to a bottle, fill it with wort containing hungry yeast and cap it the yeast goes to town on the new food (sugar) the c02 cannot escape and it gets absorbed into the beer, this gives your beer life/condition.

And what implication does reducing or increasing the amounts of sugar added make during both stages?? The same also goes with the quantity of water I use, i.e. too much or not enough??

At the fermentation stage - More sugar will make you a stronger beer, adding too much ordinary sugar to the fermenter will result in a thin tasting beer, beer is all about balance.

At bottling stage - Adding too little sugar will result in a low carbonated beer, adding too much and duck, you made a bottle bomb. A good rule of thumb for ales is 1/2 tsp per 500ml strong glass bottle.

Water - Too much and you will get a weaker beer, too little and you will have a stong beer, liken it to dilutable squash, you need to get the mix right for the end product to taste OK.

I know I’ve asked a few questions here. But I find that if I understand what is actually going on then I stand a better chance of making the right improvements as I go along for future brews.

:thumb: I hope my simplistic explanations are helpful :)

 

[jonewer]

With regards to the fermentation - there are two stages. Primary and secondary.

In the primary fermentation the yeast use the oxygen dissolved in the wort, and the sugars, to produce CO2, alcohol, and heat... and a lot more yeast.

In the secondary fermentation, the yeast has now used all the oxygen so cant carry on is it did before. The changes to the yeast's metabolism mean it starts to try and eat a variety of compounds to make its own oxygen. This is important because if these compounds arent attacked by the yeast, they can make your beer taste nasty so its important to let your beer condition for at least a few weeks after its been kegged or bottled.

Co-incidentally, the absence of oxygen in the beer now makes it very hard for most common bugs to gain a foothold and spoil the beer, though bugs that dont need oxygen or can grow on the surface can still result in a spoiled brew....

For this reason its very important that you kept the contact the beer has with air to the absolute minimum once you have pitched your yeast. Introducing more oxygen after primary fermentation is not good. So avoid splashing the beer about too much when kegging or bottling.