Most malts available to small brewers are well modified. Unless one makes a very dark beer with a high content of malt low in diastatic power (such as a Munich Dunkel – where the triple decoction mash is usually employed), the Hochkurz mash seems more appropriate to me when it comes to Bavarian Helles.
This schedule favours foam stability and mouthfeel due to its relatively high start temperatures (at 70-72 °C the Glycoproteins are only slightly decomposed). The decomposition of phytin is also less active – which results in a mash with less buffer capacity and to a lower pH in the end product.
For malts to be considered suitable for this schedule, the analysis should show the following characteristics
|Viscosity||< 1.50 mPas|
Not all malts generally available satisfy all these conditions, but they are close. To compensate, Narziss recommends doughing in at lower temperatures in the range of 45-58 °C, pending on malt characteristics.
The EVG (final attenuation) can be controlled by the first rest at 62°C (from 10-30 minutes) and the temperature attained after the first decoction is returned to the mash (70-72°C). If the final attenuation is too high, then a temperature approaching 72°C is usually chosen as the target temperature for the second decoction.
From my experiments, the best schedule for malts missing one of the above requirements only slightly is to mash-in at 55°C and then proceed as normal after heating the mash to the target temperature of 62°C very slowly (about 1°C per minute).
I was quite surprised of the effect on the mash-in temperature and the resulting final attenuation
|Temp Steps °C||62/70/77||62/72/77||58/70/77||50-62/70/77|
|EVG (attenuation) %||82.5||81.7||80.0||83.5|
(Source: Die Technologie der Würzezubereitung, Band 2 [Narziß, Beck])
Over the years, I’ve grown quite fond of the simplicity by which the results can be controlled doing this mash. I found very little difference from other classic double decoction schedules, apart from that they take longer.
Worth a try? You be the judge! For my part I pretty much settled on this method for mashing all Helles and Pilseners.