My first 'big' beer- questions

[Mogref]

I've recently started doing all-grain brews, having just kegged my 3rd. My first 3 AG brews were pretty basic, a Kolsch, an IPA, and an altbier, so on Brew Day this weekend I thought I'd try doing a higher gravity double-IPA. I'm quite fond of Brew Dog's 'Hardcore IPA' so I found a clone recipe for it and used that as a starting point. On with the questions:

1. The recipe calls for a 90min boil and I'm wondering what my pre-boil volume should be. I haven't done any formal calculations on what my boil off rate is because my propane burner seems to have two settings, simmer and boil like crazy so it's made my past boils vary a lot. Let's assume it will be a rolling boil so I'm asking about a general rule of thumb for what my pre-boil volume on a 5gal batch should be.

2. The recipe I consulted called for a 60min mash at 149F. For my previous brews I'd mashed at 154F so this sounds a bit low to me and I just wanted to make sure it's correct. I'll be mashing 17.5lbs of Maris Otter.

3. I batch sparge and on previous batches I've been happy with my efficiency. On all three I've hit above my target SG but until I did some reading recently I wasn't aware of the 'mash out' step. I would mash for 60 min, do a vorlauf and drain off the first runnings. Then I'd heat up some water to 170 and use that as my sparge water until I hit my pre-boil volume. When I read about mash out I discovered that you're supposed to raise the temperature of the mash to 170 (not just the sparge water) in order to stop conversion. I'm using a cylindrical Igloo cooler with a stainless steel braid to mash in. How essential is the 'mash out' step in the process? Why do we want to stop conversion?

4. Since it's a double IPA I'll be using a lot of pellet hops. I have a hop rig that suspends a hop bag in the boiling wort and I have a feeling that thing is going to be pretty full by then end of the boil (I'm using 4oz hops total). Any tips on getting the best hop utilization?

Thanks in advance,
-Brian

 

[_JP_]

1. The recipe calls for a 90min boil and I'm wondering what my pre-boil volume should be.

Of course it depends on the humidity outside and your altitude, but in general, I see most people estimate a 1 to 1.5 gal loss per hour. If you're really unsure, check the level periodically during the boil. When nearing your target volume, start your final (flavor/aroma) hop additions.

2. The recipe I consulted called for a 60min mash at 149F. For my previous brews I'd mashed at 154F so this sounds a bit low to me and I just wanted to make sure it's correct. I'll be mashing 17.5lbs of Maris Otter.

Between ~145° and ~155°F is the temp range generally used for single infusion mashes. The lower in the range, the more fermentable (and thus "drier") the beer will be. Mash on the upper end, you'll get more dextrins which aren't fermentable, thus lending to "mouth feel" and "richness" (and also beer farts). 149° sounds great.

3. I batch sparge and on previous batches I've been happy with my efficiency. On all three I've hit above my target SG but until I did some reading recently I wasn't aware of the 'mash out' step. I would mash for 60 min, do a vorlauf and drain off the first runnings. Then I'd heat up some water to 170 and use that as my sparge water until I hit my pre-boil volume. When I read about mash out I discovered that you're supposed to raise the temperature of the mash to 170 (not just the sparge water) in order to stop conversion. I'm using a cylindrical Igloo cooler with a stainless steel braid to mash in. How essential is the 'mash out' step in the process? Why do we want to stop conversion?

There is lots to read about this due to all the differing opinions. Generally, you'll see that the "mash out" is used by those who fly sparge, and is unnecessary for batch sparging. I don't believe it's used solely to stop the enzyme activity, but more to increase sugar solubility. Also remember when following a recipe, that it's not all about efficiency - it's about hitting your target specific gravity.

4. Since it's a double IPA I'll be using a lot of pellet hops. I have a hop rig that suspends a hop bag in the boiling wort and I have a feeling that thing is going to be pretty full by then end of the boil (I'm using 4oz hops total). Any tips on getting the best hop utilization?

Your "best" hop utilization will come from letting the pellets loose in the boil so they have the most contact with the rolling wort. A negligible difference, perhaps, but a difference none-the-less. Also, read up on "first wort hopping" if you're interested in getting the most out of your hops.