Partial mash question...

Recipe calls for partial mash. My gas oven only can be set to warm and the next setting is 200 degrees.

Im wondering how I can tell if ive extracted enough magic out of the grains.... I heard that partial mash in a kettle is in-efficient.........

My recipe:

Oatmeal Stout
5 gallons, extract with grains
OG = 1.054 IBU = 34

The grains are mashed prior to the addition of the dry malt extract. The oats have a negligible enzyme content. Hence the American six-row barley with its high enzyme content is used to saccharify the oats.

Ingredients:

6 lbs. amber, dry malt extract
1 lb. crystal malt, 60¡ Lovibond
1.5 lb. American six-row pale ale malt
18 oz. oatmeal (quick)
0.5 lb. chocolate malt
0.5 lb. roasted barley
1/2 tsp. Irish moss, for 15 min.
2 oz. Fuggles hop pellets (4.2% alpha acid), for 45 min.
Wyeast 1084, Irish ale yeast

Step by Step:

Prepare a yeast starter a day or two before brew day. Crush the specialty grains and malt, and mix them with the oats in a coarse, nylon bag. Tie up the nylon bag to seal it. Heat 3 gals. of water to 155¡ F in a pot with a lid and add the bag of grains. Keep this pot covered, maintaining a temperature between 150¡ and 158¡ F for one hour to convert the starch. This can be done, for example, by placing the entire pot in an oven preheated to 150¡ F.

Flyguy posted this link in a different post about partial mashing.
Check it out.

http://byo.com/feature/1536.html

Wow, ok theres alot more to it than what im doing.

Im keeping it in the oven for an hour and a half and poking it with the spoon to extract as much as I can.

Im in the middle of doing this right now.

I recently did a VERY similar recipe recently, although I used less oatmeal and less crystal. I also did it as a partial mash, except I used a 3 gal cooler for the mash. But a pot in the oven will work fine, too. Here are a couple of suggestions:

1. Don't worry too much about maintaining the oven at 150. Just get it close, then turn it as low as it will go. The mash isn't going to loose much heat even if the oven is cooler than 150.

2. You will want to heat your strike water a little hotter than your mash temperature because your grains will be at room temperature and will absorb some of that heat. Try about 165 F.

3. Your mash will be really thin at 3 gallons of water. You only have about 4.5 lbs of grains, so I would suggest you use 1.5 gallons of water for the mash, and use the other 1.5 gallons for 'sparge' water (to rinse the sugars out of the grains in the bag after the mash). Note that for 4.5 lbs of grains and 1.5 gallons of water, that gives a mash ratio of about 1.3 quarts water per lb grain, which is about right.

4. After the mash, put the grain bag in a big kitchen strainer over your pot to drain. Then use your remaining 1.5 gallons of water (warmed to about 170F) to gently rinse the grain bag. There are lots of sugars in there still that can be extracted.

This system works very well. I only use a cooler because it is slightly more convenient, and you recirculate to get clearer wort (but it won't matter much for a stout).

Let us know how you made out!

Well I put the grains in 4 gallons of water. Im going to partial mash for an hour and a half. I hope thats OK as I have more water for the grains to go into. I have another 1 gallon of water at 170 then and will pour that on the grain bag once done.

Hope that works OK

britishbloke said:

Well I put the grains in 4 gallons of water. Im going to partial mash for an hour and a half. I hope thats OK as I have more water for the grains to go into. I have another 1 gallon of water at 170 then and will pour that on the grain bag once done.

Hope that works OK

Click to expand...

I am sure it will be fine. The nice thing about PM brewing is that it is very forgiving. You are actually relying on the malt extracts to build up most of the beer, and the small mash is just going to add to that. But you really will notice a big improvement in flavour from an all-extract brew. Hope it turned out OK.