First Partial Mash and No Clue What Will Happen

[Flounder]

Brewed my first partial mash on Sunday. Enjoyed the experience but may have screwed some things up. It was an IPA and OG was supposed to be 1070. I decided to mash on the outdoor burner thinking I could control the temp fairly well. Wrong!! I could not for the life of me get the temp regulated. It was all over the place ranging from 140f to 170f. After 60 minutes I performed the iodine test and had not yet reached full conversion. I did the test no less than 10 times over the next hour (thats right, I mashed for a full 2+ hours) and never got the conversion reading. Since the wort was faily sweet tasting, I figured that I had gotten at least partial conversion. I forged ahead with the lauter and sparge. Boiled, added extract, and boiled again. When the wort cooled I took the hydrometer and got a 1050 reading. Not what I was shooting for but it should still be beer. Any thoughts on the process other than invest in some other way to regulate my mash temps?

 

[Bobby_M]

Getting a mash up to 170F for even a few minutes is enough to denature a good portion of your enzymes. It would be worse if you hit that temp earlier in the mash. Try to find a used cooler to mash in or at least wrap something around your pot to insulate so you don't have to keep applying heat.

 

[Chips]

I have a super-thin SS pot that you think would lose heat like crazy. However I find as long as my water + grain is nearly to the top of the pot (maybe 1" to 2" of headspace) then I don't lose a single degree over the entire hour! I usually heat 7.5 to 8L of water up to 75C (about 168F), mash 2.5kG of grain and the temp will drop to 67C (154F). I think the pot is about 18L. So far my conversion has been great!
(I use DeathBrewers stovetop method which is awesome.)

 

[kuphish]

I had a similar problem, though not as extreme, with my first couple of partial mashes. Here's how I solved it. Heat your strike water to the appropriate temperature. For my last beer, this was 166F. While heating the strike water, get two large towels and place them on a surface nearby. The towels should cross each other, such that they form a plus sign. Once your strike water reaches the target temperature, remove the pot from the heat and place it in the center of the towels (where they intersect). Dough in and stir well. Make sure the temperature has dropped to your target mash temperature (mine was 154F) and adjust if necessary. Cover the pot with the lid and bring the towels up from each side, making sure to cover all of the exposed sides of the pot and the lid. You shouldn't be able to see any of the pot if you've done it correctly and your towels are large enough. Leave the pot alone for the next 60 minutes (or however long you are going to mash). After the allotted time has passed, check for conversion and you should be ready to sparge.

Using this method last weekend, I only lost one degree over the entire sixty minutes. It definitely beats moving the pot on and off the flame and constantly adjusting the burner temperature.

Good luck!

 

[Flounder]

Thanks for the tips. If I dont go the cooler route I will try using the towels. It may also have been that my thermometer use was inconsistent from measurement to measurement. For what its worth, I was mashing 6lbs of grain w/ a little over 1.5 gallons of water. I think my efficency calculated out to 42.5% based on my OG of 1.050. Not sure if this is correct. I still think the beer will be decent if not very good.

I have become an eternal optimist after fully adopting RDWHAHB. I am amazed at the mistakes that I can make while still producing a very satisfying brew. Case in point, my first brew ever (not that long ago) was left outside halfway covered for 5-6 hours at night while cooling. No telling what got in there. Turned out to be a very drinkable pale ale (not great but not so bad that I wanted to toss it).

 

[Brocster]

Before I went to AG, I partial mashed using the following technique, and it worked very well for me.

Preheat oven to lowest temp possible, usually 170 degrees.

Get strike water to target temp, add grains to water and stir. Let sit 5 minutes. Check temp. Add hot/cool water to adjust temp if needed. Turn off oven and place pot in oven for mash period. At sparge time, place 175 degree water (volume needed) into botteling bucket. Drain first running normally the way you do. For sparging, place the grains (I use a pasta strainer) under the spigot but over the boiing kettle. I usually had the bottlling bucket on the counter, with the kettle on the floor, and the pasta strainer suspended on its handles on the seat of two chairs. Open up the spigot half way which usually leaves a spray pattern versus a stream. This will cover most of the grains, and you can use a pyrex or sauce pan to poor water slowely over parts of the grain bed not getting sparge water.

This method usually only dropped my mash 1 degree over an hour, and I was almost always dead on or very close to target OG.