Thursday, July 3, 2008

How can you save Contaminated or Infected Homebrew?

So you went out and bought all those lovely ingredients to brew up a batch of beer. You have your malt extract and hops and yeast and you brewed up your batch of beer. While doing so you were careful to sanitize (using Star San) or whatever method of sanitizing you do. You add your wort, pitch your yeast and let it ferment. After it's done fermenting you notice that there is a white film on the surface of the beer (and it's not carbonation bubbles). It doesn't look normal. And in some cases it's actually growing mold. So, what do you do? Well, first, you take a sample and smell it and taste it. If it smells and tastes fine then it's probably fine, and many times this is the case. However, if you are catching some sour flavors and odors then the chances are likely that you have an infected beer, especially if there is visible mold on your beer. Insert expletive "F***!". After all this hard work! You're cursing yourself and kicking yourself and damned if you weren't careful with sanitizing. But something went wrong. What can you do now?

If it's contaminated and not too bad to drink then you can bottle it up and condition it and start drinking it as soon as it's carbonated. Drink it young and fast so the bacteria can't overpower the actual taste of the beer.

Or, you can actually wait it out and let it sit for 6 months and let the Saccromyces, Lactobacillus or Pediococcus run its course and see if you enjoy the sour outcome of the beer.

However, there is one other way you can fight this bacteria. You can add 1 campden tablet per gallon (make sure you crush and dissolve it first) and let it sit for a week and then repitch yeast and bottle condition or keg and force carbonate. This will effectively kill the bacteria, however, depending on how far along the infection is, you're still going to have that sour taste or off taste you tasted before you caught the infancy of the infection.

Chilling your beer down after it has conditioned in the bottles will slow the growth but it won't inhibit it.

Sanitize well and hopefully contamination will be warded off, but if you do find yourself with contaminated homebrew, hopefully these tips will help you out.



blueberryboy said...

Will this ingredient spoil my Beer????
I am making a blueberry wheat beer. My ingredients include:
wheat hopped malt extract;
blueberries in light syrup;
half a can of sweetened condensed milk;
half a cup of honey;
a few table-spoons of vanilla extract;
and couple table-spoons of pecans and almonds.


I am worried that the sweetened condensed milk will ruin the batch. But I want the beer to be blueberries and cream...
I have researched and found that sugar prevents bacteria from growing, but WILL THE SWEETENED CONDENSED MILK GO BAD? I am confused...

I have heard that the sweetened condensed milk is processed and it is like sugar??

I am getting mixed responses about this...

Please do not tell me that milk goes bad and it gets sour...I understand that...I want to make sure because this is different

It will take four weeks before it becomes drinkable, and I am hoping the sugar will prevent anything bad from happening.

I also added a pinch of salt to help prevent any problems...

The batch has a volume of 2 gallons...I added about 6 oz. of sweetened condensed milk...

Even if it does go bad, it might taste good...???

Could I add more yeast to ferment the condensed milk??

p.s. there is an accumulation of foam at the top and I am not sure if this is bad or normal

Homebrew Junkie said...

The milk will ruin the batch. Once it's done fermenting out the sugars in the SWM then the milk is going to curdle and turn sour and make your beer taste awful.

My advice, use lactose next time. It's a milk based substance used for brewing that will add some sweetness to your beer without turning it sour.

The foam on the top is krausen. It's typical with a good fermentation.

Good luck.