Secondary Fermentation

[Guest guest]

Let me see if I have this straight. I just read Ed's great

information on secondary brewing. I'd like to ask the older brewers

(and Ed) if I have grasped the concept of secondary brewing

correctly. Thank you in advance for your comments and corrections.

Please see if I have fully grasped this concept.

Here goes:

After one brews their Kombucha they can just put their brewed kt in a

bottle and refrigerate and be done with it. At this point in time

the cool temperature will inhibit any bacterial and yeast growth and

the brew will remain about the way it was when went into the bottle

as long as it is below 40º F. degrees. If one leaves the KT at room

temperature and the bottles have oxygen in them the bacteria will

convert the alcohol to acetic acid, making the brew turn sour, which

we don't want.

Ed's site says: " The yeasts produce alcohol from the glucose which

the bacteria than convert to acetic acid. Both the yeast and the

bacteria compete for the glucose which the bacteria convert to

gluconic acid. "

If instead one removes the oxygen you are able to get a fizzy brew.

This happens as the yeast, (which unlike the bacteria, can work

without oxygen), produces CO2 while eating the remaining glucose.

Again, if we don't care about fizz we can stop there and just place

the bottles in the refrigerator.

However, if we LIKE fizz then we will cut off the oxygen supply so

the bacteria will stop competing with the yeast. The yeast will then

produce the bubbles by turning the remaining sugar into alcohol and

thereby produce gas. Yeast can continue to be active down to 40º F

degrees. As long as glucose remains in the brew and the brew is put

somewhere warmer than 40º we will have gas forming (and danger of

explosion).

If we put an airlock on the bottle by either purchasing one with a

water air lock or by putting a balloon on the top of the bottle we

can allow most of the CO2 to escape until we are left with a brew

that is the sweetness and bubble quality that we like. The air lock

works sort of along the lines of the gas trap under your sink. The

water in part of the looping system allows gas to escape without

allowing any gas (oxygen) to enter. In this way we can get a drier

brew but with more bubbles. It will also have more alcohol.

If we don't want to use the airlock we can just throw add fructose to

retain some sweetness (or actual fruit) into the bottle, thus

increasing the sweetness but not in a form the yeast can eat it. We

then make sure there is no air in the bottle, cap the bottle, and

allow it to sit for about two days.

We can use a plastic bottle as a tester to show us how much gas is

being produced in the glass bottles whioh will tell us if we need to

burp the bottles. After about two days we then put the KT in the

fridge so that we don't have to worry about explosions.

I assume if we are drinking the KT within the week and the

temperature is not too high we may leave the KT out longer but

generally we would not want in order to reduce worry of bottles

exploding.

If we want the brew to be sweet without more gas we add fructose. If

we want more gas and less sweet we add sugar in the form of glucose

or dextrose. As long as any of the glucose remains in the brew, and

the brew is kept at a temperature between 40º - ~75º F. degrees it

will produce gas which means possible explosion.

If we do not want additional alcohol in our KT we can pasteurize the

brew after the second stage ferment by heating it between 140-160º F.

degrees for 10-20 minutes.

Lori