Kegconnection Complete Starter Kit and More Giveaway!


Home Brew Forums > Home Brewing Beer > Lambic & Wild Brewing > How to enjoy a sour?

Reply
 
LinkBack Thread Tools
Old 08-12-2010, 03:38 PM   #31
King of Cascade
Feedback Score: 0 reviews
Recipes 
 
Join Date: Feb 2008
Posts: 663
Liked 5 Times on 5 Posts
Likes Given: 2

Default

Quote:
Originally Posted by ryane View Post
Brett doesnt produce lactic, it can produce acetic acid though, but that requires a bit of oxygen and no other fermentation to be occuring
It absolutely produces Lactic acid and Acetic in the presents of oxygen

See slide 19
http://www.homebrewersassociation.or...teve_Piatz.pdf
__________________

Last edited by King of Cascade; 08-12-2010 at 04:10 PM.
King of Cascade is offline
 
Reply With Quote Quick reply to this message
Old 08-12-2010, 06:12 PM   #32
ryane
Feedback Score: 0 reviews
Recipes 
 
Join Date: Nov 2008
Location: Phoenix, AZ
Posts: 779
Liked 5 Times on 5 Posts

Default

Quote:
Originally Posted by King of Cascade View Post
It absolutely produces Lactic acid and Acetic in the presents of oxygen

See slide 19
http://www.homebrewersassociation.or...teve_Piatz.pdf
Ive never heard of anyone else claiming this, and he doesnt have any references, do you know of any actual research that shows this is true?
ryane is offline
 
Reply With Quote Quick reply to this message
Old 08-12-2010, 06:18 PM   #33
GilaMinumBeer
In yo' garage, steelin' yo parts.
HBT_LIFETIMESUPPORTER.png
Feedback Score: 0 reviews
 
GilaMinumBeer's Avatar
Recipes 
 
Join Date: Jan 2008
Location: Oblivion
Posts: 47,079
Liked 4633 Times on 4315 Posts
Likes Given: 57

Default

I find I enjoy Flemish Sours so much that you could prolly spike Malt Vinegar with some Vodka and I'd drink it.

__________________

Last edited by GilaMinumBeer; 08-13-2010 at 01:42 PM.
GilaMinumBeer is offline
 
Reply With Quote Quick reply to this message
Old 08-12-2010, 09:58 PM   #34
ryane
Feedback Score: 0 reviews
Recipes 
 
Join Date: Nov 2008
Location: Phoenix, AZ
Posts: 779
Liked 5 Times on 5 Posts

Default

Quote:
Originally Posted by King of Cascade View Post
It absolutely produces Lactic acid and Acetic in the presents of oxygen

See slide 19
http://www.homebrewersassociation.or...teve_Piatz.pdf
Ok so i did some digging, technically you are correct, but practically speaking relying on brett to produce lactic acid is wrong

brett will produce small trace amounts of lactic acid that are excreted ~1-10ppm, However, the taste threshold for lactic acid is 400ppm, so it will produce a small amount but it will be 40times less than you can taste

Last edited by ryane; 08-12-2010 at 10:14 PM.
ryane is offline
 
Reply With Quote Quick reply to this message
Old 08-13-2010, 02:04 PM   #35
King of Cascade
Feedback Score: 0 reviews
Recipes 
 
Join Date: Feb 2008
Posts: 663
Liked 5 Times on 5 Posts
Likes Given: 2

Default

Quote:
Originally Posted by ryane View Post
Ok so i did some digging, technically you are correct, but practically speaking relying on brett to produce lactic acid is wrong

brett will produce small trace amounts of lactic acid that are excreted ~1-10ppm, However, the taste threshold for lactic acid is 400ppm, so it will produce a small amount but it will be 40times less than you can taste
Interesting…could you provide a link? It’s not that I’m challenging your findings but would like to do some research myself. I found Steve Piatz seminar to be very interesting at NHC and would like to learn more.
__________________
King of Cascade is offline
 
Reply With Quote Quick reply to this message
Old 08-14-2010, 09:41 PM   #36
ryane
Feedback Score: 0 reviews
Recipes 
 
Join Date: Nov 2008
Location: Phoenix, AZ
Posts: 779
Liked 5 Times on 5 Posts

Default

Quote:
Originally Posted by King of Cascade View Post
Interesting…could you provide a link? It’s not that I’m challenging your findings but would like to do some research myself. I found Steve Piatz seminar to be very interesting at NHC and would like to learn more.
So my personal digging into literature turned up little to no discussion of lactic acid production by brett, what I found was related to the krebs cycle which is a normal metabolic pathway for bacteria and even you, however, this lead me to believe that there is no mechanism for lactic fermentation by brett, to further address this issue I contacted Chad Yakobson, who is a brewer with Odell, and who recent received a masters in brewing, his thesis was on brett fermentations this is what he had to say.....

"there is no direct texts which talk about lactic acid production. The main acids produced and transported out of the cells are acetic acid, capric acid, caproic acid and caprylic acid. The reason nothing exists on lactic acid is because it doesn't produce it in quantities that have any organoleptic impact. Most strains most likely form almost none. Acetic acid on the other hand is heavily produced in aerobic environments, and therefore has been heavily concentrated on in previous studies. How most of the studies concerning compounds with yeast occur is through observing esters and then looking at the production of the acid which made up part of that ester and looking for its origin. If Brettanomyces species produced lactic acid, it would have been written about academically already, but instead it has been shown that without exogenous additions of lactic acid, minute amounts of ethyl lactate are formed if at all.

In my study I observed ethyl lactate production in every fermentation. All the fermentations which observed pitching rate and no lactic acid addition had between .18 and 1.81 mg/l. When adding 100 mg/l between a 5 and 10 fold increase in ethyl lactate was observed. This trend continued all the way up to 3,000 mg/l which I observed too.

That data is what leads me to believe somewhere between 1 and 10 mg/l is excreted out of the cell during various metabolic processes. If you go and read up about the TCA cycle and then read about the activity of the EMP pathway in Brett and lowered amino acid synthesis during aerobic growth a spotty conclusion can be made that somewhere some is being produced through various steps and not fully consumed. But Brett does not lactic ferment, this is a whole different process, and as those pathways do not appear to exist in the genome and they have not been observed by previous researchers. Lactic acid is not produces by Brettanomyces the way a lactic ferment takes place in Lactic acid bacterias.

All this will be up on the site soon and you can read all about various pathways and secondary metabolites. But it takes time to get content up and converted for the web."
ryane is offline
 
Reply With Quote Quick reply to this message
Reply


Quick Reply
Message:
Options
Thread Tools


Similar Threads
Thread Thread Starter Forum Replies Last Post
Wanted: Sour beer lovers to taste a sour mash beer OldRalHoleBrewing Lambic & Wild Brewing 12 09-03-2012 04:16 AM
My Red isn't sour chase Lambic & Wild Brewing 26 07-10-2010 05:21 AM
Help with first sour JayInJersey Lambic & Wild Brewing 4 05-14-2010 06:40 PM
Always sour mash for sour brews? jvlpdillon Lambic & Wild Brewing 4 04-27-2010 10:21 PM
should I try and fix this sour Chester Lambic & Wild Brewing 6 08-16-2009 04:40 AM