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A protein rest may not be necessary, but there are other benefits to other lower rest temperatures.
Quote from: Kit B on November 13, 2015, 06:46:28 amA protein rest may not be necessary, but there are other benefits to other lower rest temperatures.>=132 deg F seems to be a popular one, especially in the monasteries.
A short rest - say 10 to 20 minutes - at 131-134ish will not hurt body or foam because it is out of the highly active range of peptidase, which breaks medium proteins into small proteins and amino acids. With continental Pilsner malt around a protein level of 10-10.5% and a kolbach index of 38-41, you may see a reduction in chill haze as well as better foam and body due to the activity of proteinase, which breaks large proteins (the ones that cause chill haze) into medium chain proteins.I use a 10 minute rest at 131 and definitely see a reduction in chill haze vs when I don't. I know Gordon Strong does the same thing for the same reasons.The only time a protein rest is not recommended is when the kolbach index is over 41. Most US and UK malts fall into this category.
Quote from: techbrau on November 13, 2015, 09:09:28 amA short rest - say 10 to 20 minutes - at 131-134ish will not hurt body or foam because it is out of the highly active range of peptidase, which breaks medium proteins into small proteins and amino acids. With continental Pilsner malt around a protein level of 10-10.5% and a kolbach index of 38-41, you may see a reduction in chill haze as well as better foam and body due to the activity of proteinase, which breaks large proteins (the ones that cause chill haze) into medium chain proteins.I use a 10 minute rest at 131 and definitely see a reduction in chill haze vs when I don't. I know Gordon Strong does the same thing for the same reasons.The only time a protein rest is not recommended is when the kolbach index is over 41. Most US and UK malts fall into this category.Best says their pils kobalch is 36-45. Do you average that? Or do you have to know the number for your specific lot of malt?
Quote from: klickitat jim on November 13, 2015, 04:06:05 pmQuote from: techbrau on November 13, 2015, 09:09:28 amA short rest - say 10 to 20 minutes - at 131-134ish will not hurt body or foam because it is out of the highly active range of peptidase, which breaks medium proteins into small proteins and amino acids. With continental Pilsner malt around a protein level of 10-10.5% and a kolbach index of 38-41, you may see a reduction in chill haze as well as better foam and body due to the activity of proteinase, which breaks large proteins (the ones that cause chill haze) into medium chain proteins.I use a 10 minute rest at 131 and definitely see a reduction in chill haze vs when I don't. I know Gordon Strong does the same thing for the same reasons.The only time a protein rest is not recommended is when the kolbach index is over 41. Most US and UK malts fall into this category.Best says their pils kobalch is 36-45. Do you average that? Or do you have to know the number for your specific lot of malt?When I contacted them about the need for a protein rest they said it wasn't needed for their Pils malt but if you have problems try doughing in low and immediately raise slowly to your first beta rest. This what I've been doing with good results.