[hopfenundmalz]

I was looking at this again,
https://beersensoryscience.wordpress.com/2010/11/15/chemistry-of-beer-aging/
the last part now jumped out at me after the recent LODO Brewtan B kerfuffle.

"Some steps that this paper recommends for maximizing the freshness of beer:

Minimize formation and activity of ROS, by limiting molecular oxygen pickup and copper and iron levels.  Chelation of metal ions and use of anti-oxidants are mentioned.
Sulfites are mentioned to be among the most potent anti-oxidants used in brewing.  Some is formed by yeast, but most of it must be added by the brewer (must be labeled in US), if so desired."

The paper referenced.
http://depa.fquim.unam.mx/amyd/archivero/ARTICULOGRUPO8_25527.pdf

[ynotbrusum]

Interesting article, Jeff.  A lot of bio-chemistry there - I bobbed to the surface repeatedly to avoid drowning in a work so far over my head!  But I recognize some of the terms and I would say that reducing oxygen up front, reducing oxidative-enhancing processes and ingredients and exploring anti-oxidant additives, including Brewtan-B (tannic acid-derived anti-oxidant) or ascorbic acid, should all help for reducing the staling process.  Sulfites are well known to the winemakers among us, so maybe there is a role for it in brewing, if flavors are not affected adversely by its use.

[homoeccentricus]

Table 2 is interesting: Strategies for dealing with beer staling according to Bamforth (2000b).
I had better start anaerobic milling!

[homoeccentricus]

Here's another interesting article, on how different beers age differently: http://www.lambic.info/images/f/f3/Vanderhaegen2007Agingcharacteristicsofdifferentbeertypes.pdf


For now I've only looked at the conclusion. For instance,
"In dark and high alcoholic beers,
Maillard reactions are the major staling processes and here
procedures to reduce the reaction rate must be considered
to improve the flavour stability. This can be done by reduc-
ing the thermal load on wort during the beer production
process, leading to less reactive Maillard intermediates."

[hopfenundmalz]

Interesting article, Jeff.  A lot of bio-chemistry there - I bobbed to the surface repeatedly to avoid drowning in a work so far over my head!  But I recognize some of the terms and I would say that reducing oxygen up front, reducing oxidative-enhancing processes and ingredients and exploring anti-oxidant additives, including Brewtan-B (tannic acid-derived anti-oxidant) or ascorbic acid, should all help for reducing the staling process.  Sulfites are well known to the winemakers among us, so maybe there is a role for it in brewing, if flavors are not affected adversely by its use.

Yes, the low O2 is used by many breweries that have the equipment. The Brewtan B chelates the trans metals.

Why not try both together?

[ynotbrusum]

Agreed, along with packaging under CO2 as discussed by many and now incorporated into my racking process with purged receiving kegs.  I haven't tested out the length of storage permissible, as yet, because my beers are being consumed by my friends too quickly, still.

[HoosierBrew]

Yeah, thanks for posting, Jeff. I'm definitely on board with Brewtan B, have purged kegs with CO2 for awhile, and am experimenting with kegging with ascorbic again. I'm looking forward to cracking these bottles of Ofest and NG Pils that I bottled from the kegs and sampling at 6 months. That'll be the final test.

[hopfenundmalz]

I have to get some Brewtan B. I did a lager with LODO techniques, kind of, and will keg that tomorrow.

There was still some copper in the boil kettle. I can see where some Brewtan B might help that from being an issue. I will say it that many small German breweries have copper Kuhlschiffs and such in the brewery. The small breweries don't often worry about shelf life, as they may make <1000 bbl a year and the beer is consumed quickly. The larger breweries that are said to use LODO are making beer that often needs a long shelf life, so for a Homebrewer we have options.

[homoeccentricus]

During the Easter holiday I was in Germany and bought beer in a trusted beer shop in Bonn. Two months later I organized a German beer tasting with some friends. Result: almost all beers were severely oxidized (notable exceptions: the Zum Uerige altbier, which i had bought at the brewery). I have to admit that I hadn't checked expiration days, because in Belgium that's usually not necessary, and that a number of beers had expired when we tasted them. Still, we were baffled. They all had trans-2-nonal. And although I do not typically brew German lagers, I am starting to take anti-oxidative measures.

Edit: I hate Swype

[wobdee]

I've been playing around with both SMB and Brewtan together for a few batches now. I also use SMB at kegging. Flavor and aroma has been sticking around down to the last drop.

[hopfenundmalz]

During the Easter holiday I was I Germany and bought beer in a trusted beer shop in Bonn. Two months later I organized a German beer tasting with some friends. Result: almost all beers were severely oxidized (notable exceptions: the Zum Uerige altbier, which i had bought at the brewery). I have to admit that I hadn't checked expiration days, because in Belgium that's usually not necessary, and that a number of beers has expired when we tasted them. Still, we were baffled. They all had trans-2-nonal. And although I do not typically brew German lagers, I am starting to take anti-oxidative measures.

Zum Uerige has a reputation for not traveling well. I have found it does go off, one bought at the brewery was starting to stale after a month when I shared it and other Alts with friends who had never had them fresher than we get in the import distribution chain. You can find plenty of off bottles in Germany. When I liver there I found that I should only buy a case of beer if the stack was high, no dust on the bottles, and even then grab a case that was not on the top to avoid skunking from the lights.

Uerige is another brewery that uses a kuhlschiff (cool ship), and when the wort has dropped to about 60C, it goes over a copper drip chiller (Baudelot chiller). Plenty of O2 exposure there, but  the yeast will go to work after the chiller.

[homoeccentricus]

On a side note: I had the Doppelsticke, and it did nothing for me. Now that I've read it was developed for the American market I understand why

[Philbrew]

I have to get some Brewtan B.

Is there an online source for Brewtan B?

[homoeccentricus]

In Belgium, yes

[HoosierBrew]

Is there an online source for Brewtan B?

Here ya go:   http://www.ibrew.com.au/products/brewtan-b