Beer Forum

This is a forum for enlisted and new recruits of the BN Army. Home brewers bringing it strong! Learn how to brew beer, trade secrets, or talk trash about your friends.
http://www.terrencetheblack.com/forum/

Plating samples from my beer.

http://www.terrencetheblack.com/forum/viewtopic.php?f=19&t=16738

Page 1 of 1

Plating samples from my beer.

Posted: Tue Sep 08, 2009 1:48 pm
by Proofman
I thought you all might find this interesting.

I was working on an IPA recipe. I wanted something with a huge floral hop flavor, smooth bitterness, with a solid malt backbone. I have recently become a fan of "hop-bursting" that Jamil wrote about. Here is what I came up with:

Batch Size: 5.50 gal
Boil Size: 7.25 gal
Estimated OG: 1.065 SG
Estimated Color: 12 SRM
Estimated IBU:62 IBU
Brewhouse Efficiency: 80.00 %
Boil Time: 90 Minutes

Ingredients:
------------
Amount Item
1.50 lb Light Dry Extract (8.0 SRM)
5.00 lb Pale Malt, Maris Otter (3.0 SRM)
1.00 lb Aromatic Malt (26.0 SRM)
3.00 lb Pilsner (2 Row) (2.0 SRM)
0.50 lb Special Roast (50.0 SRM)
0.21 lb Caramel/Crystal Malt -120L (120.0 SRM)
0.5 oz Amarillo Gold [8.00 %] (30 min)
0.5 oz Centennial [8.70 %] (30 min)
1.5 oz Amarillo Gold [8.00 %] (20 min)
1.5 oz Centennial [8.70 %] (20 min)
1.00 oz Simcoe [11.90 %] (10 min)
1.00 oz Amarillo Gold [8.00 %] (0 min)
1.00 oz Simcoe [11.90 %] (0 min)


Mash Schedule: Single Infusion, Light Body, Batch Sparge

I brewed it and I forgot to add the campden tablets for the chloramines.

All through fermentation it tasted awesome. I couldn't wait for it to be done. I checked it 3 weeks after bottling and there was no carbonation. I resuspended the yeast in the bottles and waited a couple of more weeks and there was carbonation. However, the beer changed. There was a plastic/band-aid/medicinal flavor. I figured it was an infection or the chloramines. So I decided to plate some samples from a couple of beers.

I stuck the loop straight into the beer. I didn't agitate the bottle at all.

http://i32.photobucket.com/albums/d8/Bu ... G_0248.jpg

I rolled the bottle some to re-suspend the yeast
http://i32.photobucket.com/albums/d8/Bu ... G_0247.jpg

This one is a control. I opened the dish on the counter for the amount of time it took me to plate the other two.
http://i32.photobucket.com/albums/d8/Bu ... G_0246.jpg


Looks like I got some bugs in my beer. :(

Re: Plating samples from my beer.

Posted: Tue Sep 08, 2009 3:00 pm
by brewinhard
That sucks, but very interesting petri dishes. The top one looks like some molds got introduced along with bacteria/wild yeast. How long did it take for the plated cultures to show growth?

Re: Plating samples from my beer.

Posted: Tue Sep 08, 2009 7:06 pm
by ajdelange
I wouldn't be too hasty in concluding that infection is your problem though I can't really read the plates from the photos. The flavor you describe is definitely that associated with chlorphenolics. Are there other off flavors or smells? Are the colonies in the first dish along the lines over which you dragged the loop? What are the colonies morphologies? What do smears from them look like under the microscope?

What I am getting at is that unless you were under a laminar flow hood it is quite possible that you picked up a spore or 2 on the test plates and not on the control. If the mold colonies are not where you passed the loop then the spores were probably not in the beer. If the colonies along the path of the loop don't look like yeast, or prove, upon microscopic examination, to be wild yeast or bacteria then you do indeed have an infection but were that the case I'd expect you notice something else wrong with the beer besides the bandaid/plastic smell.

All times are UTC - 8 hours
Page 1 of 1