Re: turbid mash
I've read a fair bit of Mike T blogs, as I'm new to brewing funky beers, & am getting ready to do one myself. I disagree that torrified/ flaked wheat can be used in place of raw wheat, simply for the fact that you'll run the risk of complete conversion in the mash. The starches in raw wheat are insoluble, so that beta amylase cannot convert them (as I understand it, anyhow). That being said, I used to be under the assumption that before using the raw wheat, I'd better boil it first... wrong!
Enter the reason for hot sparging... During the hot sparge, you'll be solublizing, and therefore extracting that starch into the wort. In theory, a single, high temperature saccharification rest allowed to run its course, will still leave plenty of undissolved starch for extraction during the sparge.
Expect low efficiency. The reason I believe sixbillionethans had a 96% efficiency (which can only be a result of complete conversion) is simply because the turbid wort was returned before the saccharification rest, and therefore (since the starch is now soluble) all the starch converted, making the whole turbid mash rather pointless.
Here is an clipping that I found useful, although we'll be mashing a more simplified version...
Turbid Mashing for the Homebrewer
The following is a conversion of the Cantillon turbid mash schedule to homebrew scale.(3) Based on the information presented in the article from Brewing Techniques, the Cantillon Brewery gets approximately 33-34 pts/lb/gallon.
The grist is composed of 34% Raw Wheat and 66% Malted Barley. A number of assumptions have been made in scaling down this mash schedule. It is assumed the we want to end up with a wort with an original gravity of approximately 1.048. It was also assumed that a yield of 30 points/pound/gallon would be obtainable using this method. As will be seen this assumption was not valid for this mash schedule carried out using the equipment and methods described. Your own individual results may vary.
The recipe was designed to provide 5 gallons of wort with an original gravity of 1.048. If we assume that we can get 30 points/pound/gallon then we need a total of 240 points.
We will assume one pound of grain yields 30 points. We want a 1.048 OG wort of 5 gallons. This is 48 points X 5 gallons = 240 points total. 240 points/30 points/lbs of grain = 8 lbs of grain.
For 5 gallons you will need 240 pts total. 240 pts/30 pts/lb/gallon = 8 lbs of grain Based on this calculation we will need 8 lbs. of grain. For a further explanation of mash calculations see reference (9).
The grist is 66% malt and 34% raw wheat. The barley malt fraction is 66% of 8 lbs which is 8 lbs X 66% = 5.3 lbs malt. 8 lbs total minus 5.3 lbs of barley malt equals 2.7 lbs of raw wheat.
The Cantillon schedule calls for mashing in 1300 kg grain/850L water (2860 lbs/900 qt) = 3.2 lbs/qt or 0.3 quarts of water/pound. We have 8 lbs of grain X 0.3 quarts = 2.4 quarts of water. In all of the following steps the temperature and water additions were taken directly from the Cantillon schedule as published and scaled accordingly.
1.) In kettle #1 add water at 144 F(62 C) to the crushed grain to achieve a temperature of 113 F (45 C) (about 2.4 quarts of water). Mix grain and water thoroughly and allow to rest at 113 F for 10 minutes. This amount of water is enough to just wet all the grain and flour. The mash needs to be stirred very well to make sure all the grain is wetted and no clumps of flour are present. Total time for this step is about 20 minutes, with the temperature rest included.
2.) Next, add enough boiling water (212 F)(100 C) to the mash to bring the temperature to 136 F (58 C). Do this over the course of 5 minutes making sure to mix thoroughly. Allow the mash to rest for 5 minutes at this temperature. Remove about a quart of liquid from the mash and add to kettle #2 and heat to 176 F (80 C). It will take about 3.5 quarts of water to raise the temperature to 136 F and you will end up with a very soupy mash with plenty of excess liquid. The liquid taken off should have the appearance of milk. Once heated it will clear up and large particles of hot break will form.
3.) Add more water at 212 F (100 C) to the mash over the course of 10 minutes to bring the temperature to 150 F (65 C), again with constant mixing. It will take about 5 quarts of water to achieve this temperature. Allow the mash to rest for 30 minutes at 150 F (65 C). At this point the mash will be very soupy and the liquid much less milky in appearance.
4.) Next remove 4 quarts of liquid from kettle #1 and add to kettle #2. Continue to heat kettle #2 at 176 F (80 C). The liquid removed from kettle #1 will be very cloudy but not quite as milky as the liquid previously removed.
5.) Add more 212 F (100 C)water to kettle #1 to bring the temperature to 162 F (72 C) and allow to remain at 162 F for 20 minutes. Again it will take about 5 quarts of water to reach the rest temperature. The mash should be very thin and soupy with a great deal of small particulate matter in the liquid portion of the mash.
6.) After the 20 minute rest the liquid in kettle #1 is run off and brought to a boil in a 3rd kettle (#3). Enough of the liquid in kettle #2, at 176 F, is added back to the mash in kettle #1 to bring the mash to a temperature of ~167 F (75 C). The mash is allowed to rest at 167 F for 20 minutes. Any liquid left in kettle #2 can be added to the previously collected run off in kettle #3. It will take most all the liquid in kettle #2 (~1.25 gallons) to raise the temp of the mash to 167 F.
7.) After 20 minutes the wort in kettle #1 is recirculated to clarify it and the sparging with 185 F (85 C) water is begun. Sparge until run off gravity has dropped to less than 1.008 and boil it with the previous run off from kettle #1. Boil the wort, now in kettle #3, until the volume is reduced to ~ 5 gallons.
8.) As the wort begins to boil it is hopped with approximately 4 ounces of aged hops as described in the Hops section. With all the water additions and sparging you will end up with about 9 gallons of wort. Total boiling time to reduce this volume to 5 gallons will depend on what kind of setup you have. At the beginning of the boil the wort will be cloudy and full of large flocculent break material. As the boil proceeds the wort should clarify as the proteins continue to coagulated and the starch is solubilized.
After boiling, the wort can be cooled using your method of choice. This method of mashing does not seem to yield the large amount of break that a typical all malt infusion mash will yield. But as stated earlier your results may vary depending on your equipment and technique.
Using this method yielded a wort with an OG of 1.040. This is ~ 25 pts/lbs/gal. Thus the mash efficiency was not as high as that obtained at Cantillon. The yield could probably be improved by extending the times for the various rest steps. Also it may be a good idea to heat the liquid withdrawn from kettle #1 each time at a very slow rate. To play it safe you may want to start out with a larger grain bill based on the more conservative yield of 25 pts/lb of grain.