Read this...?!

[Phil]

http://www.draymans.com/articles/arts/14.html

Seem's interesting?
Might try it?

any comments?

[Steffan]

In my limited experience it's standard operating procedure in small micros throughout the Pacific Northwest of USA.
{shrug}

[crassbrauer]

“Hoch-Kurz”, i.e. high-short, mashing, (62 - 72 - 78°C) is a method only to be used with highly modified Continental-style malt. It can either be done with decoction or infusion. The resulting beers are nicely crisp and pleasantly drinkable (therefore, it's primarily used for Pils and Helles).

However, if your malt is poorly modified, you must mash in at a much lower temperature, in order to allow for the proteolytic enzymes to work (around 50°C). His "brewer's window" is open at the wrong spot on the temperature scale for mashing poorly modified malt.

By the way, this only applies to Continental-style raw materials and brewing methods. British malt is generally more highly modified and can be mashed at a higher, single temperature, although extract is still wasted when compared to German brewing. British ales don’t need foam and British maltsters use more winter barley, so malting (incl. proteolysis) can be more intensive/extensive in the UK.

Another thing this guy seems confused about regarding his "brewer's window" is this: “When malt is thoroughly modified (well-modified) with just adequate enzymes the brewers window of mashing temperature is lower on the temperature scale, say 65 – 67°C.”

The window he talks about, actually 65 – 70°C, should be avoided during mashing, because that is the optimum for lipases which release fatty acids into the mash – very undesirable! Hit 62°C and heat the mash up to 72°C to avoid staying at their optimum (they have another one at 35 – 50°C).

Looking at the whole website, it certainly seems like he went to a lot of effort to educate the folks Down Under about brewing, which is a laudable endeavor.

[aswissbrewer]

Adding enzymes to a barley malt mash, adding antoxidants to the mash - surely this is not necessary, especially if you pride yourself as a craft brewer?

This is technical brewing not craft brewing.

[crassbrauer]

If brewers are brewing all-malt beers and need to add enzymes, it's usually to make up for lack of know-how or poor raw materials. Ultimately, in my experience, quick-fixes and short cuts usually show through in the finished beer. (Some of the larger breweries around do put a blanket of CO2 or nitrogen over their grain bed, though, while lautering, to avoid hot-side aeration in the brewhouse.)

[Alley Kat]

The window he talks about, actually 65 – 70°C, should be avoided during mashing, because that is the optimum for lipases which release fatty acids into the mash – very undesirable! Hit 62°C and heat the mash up to 72°C to avoid staying at their optimum (they have another one at 35 – 50°C).


According to the MBAA Practical Handbook for the Specialty Brewer lipoxygenase is active "up to 55°C and is quickly destroyed at 65°C".

Cheers!
--Neil Herbst
Alley Kat Brewery

[dick murton]

Traditional British mashes using (as stated) highly modified malt - temperatures typically between 63 and 68 C, typically 60 minute stand, but some use longer or shorter times, depending upon the attenuation limit wanted, whilst ensuring complete starch conversion, and sparging 76 or 77 C. No proteolytic stand, because there is no means of raising the temperture consistently. Mash bed thickness of 25 cm is far too thin - it will be stone cold before you know where you are. Bed depths, well I've used 5 (150 cm) foot + deep, down to about 18 inches (45 cm) depths in the same tun. And we definitely suffered excessive cooling with the shallow beds

Agree about the proteolytic stand - 50 to 54 C as there is no proteolysis much above this, and it is only required for less well modified malts or when using some adjuncts

The poorer extracts in traditional British tuns are really a function of the single vessel, requiring a coarse grind, which slows the extraction rate, plus the generally deeper beds. We could get 97 % lab extract which wasn't far off a lauter tun of that vintage.

Shame about the pitch of the article - I wasn't sure if it was meant to be a more technical article of the brewing process at his brewery, or an instructional note. It was too technical for a brweery script, and unfortunately got a few things wrong / confused for a tech article - but as said previously, at least he is trying

[aswissbrewer]

The poorer extracts in traditional British tuns are really a function of the single vessel, requiring a coarse grind, which slows the extraction rate, plus the generally deeper beds. We could get 97 % lab extract which wasn't far off a lauter tun of that vintage

Interesting contribution Dick , many thanks!

I use a single vessel and a coarse grind. What kind of lab extract are you talking about? (70-80%?) and how long would the run off take for 97% and say 2 feet bed depth? AND what kind of extract levels would be expected for last runnnings?

[dick murton]

I'm not used to degrees Plato and expressing extract as percentages like this. Give me a couple of days to do some calculations.


We were taking our runnings down to about 4SG (1P). I know some people might consider this low, but we didn't suffer from it. Don't forget this is british ale, with a fast turnover, much of it going into cask, with a four week shelf life. From memory, normal mash depth was around 150 cm - to produce 400 hl, but when we did the shallow mashes to brew smaller volumes, circa 100 hl, but also at a lower gravity, we lost a few degrees of extract because the top of the mash cooled off too quickly. I know we had residual starch left at the end, simply becasue the grist frose a couple of centimetres above the wort level, and got cooler - a function of the large headspace under those conditions and being dry.


Cheers

[crassbrauer]

Alley Kat,

You are correct regarding lipoxygenase (LOX). It is active primarily between 45 - 55 °C; its pH optimum is between 6.5 - 7.0. There are, however, many other enzymes to consider, one of which is lipase. Lipase is active primarily between 55 - 65 °C. The pH optimum of lipase is between 6.8 - 7.0. (Lowering your mash pH to as far away from this range as possible is yet another reason acidify your mash.)

Professor Narziss writes that an increase in fatty acids in the mash occurs in the temperature ranges of 35 - 50 °C and 65 - 70 °C. Lipids are broken down to glycerides and glycerin plus fatty acids through the action of the lipases (a number of different enzymes). The oxidation of fatty acids occurs through the action of LOX, primarily at 35 - 50 °C. This results in less linoleic acid and linolenic acid in the mash compared to the amounts found in the malt.

[Larry Horwitz]

in my experience there is no malt on the market that isn't fully modified and loaded with enzymes. do the program, save time in your day, and you will still have the ability to make world class beers.

cheers