I thought it might be helpful to see a step by step guide to partial grain brewing with pictures.
The first step, after deciding on a recipe, is to roast the grains. For this recipe I am using oats. Usually with oats you want to wet roast them, which means get them wet first. But either way, you spread the grains out on a tray for the oven.
If you are doing a dark beer, you’ll want to start on a low temperature and gradually increase the temperature. This will darken the grains as opposed to burning them. I did these oats for 1 hour at 250 f. I wasn’t going for any darkness, just a nutty flavor. Let these sit for a few days after roasting them.
For my oats I use Bob’s Red Mill certified gluten free oats. If you use oats, make sure they are gluten free!
On brew day, I always get all of my ingredients out as well as the recipe.
Then fill your brew kettle with water for the steeping of the gluten free grains. Remember, you want the water warm to hot. But holding it at a specific temperature doesn’t matter because you aren’t trying to convert the grains. These grains are not malted and not enzymes are being added. I use paint strainer bags for my hops and grain immersions.
Notice how clear the water is at the start.
Now notice the murky color of the water. This is following a 30 minute immersion of the gluten free grains.
Then bring the water to a full boil and start adding the specific ingredients at the appropriate times. For 5 gallon batches, I do a 3 gallon boil. This is simply because I don’t have a wort chiller and it takes 5 gallons FOREVER to cool. However, if I start with 3 gallons I usually end with 2.5 gallons and that is much easier to cool. I top it off to 5 gallons. This doesn’t impact flavor and is a common method for those who do kitchen top home brew.
This is an important and often overlooked step: drinking a prior brew while reading a good book. You have to do something while those hops impart their flavors.
This is the finished product. Hanging on the right side is my hop bag. This was an IPA so it was hop heavy. You can see little bits of hops floating around in the wort. Even using a bag they still leak out. You’ll want to strain those out.
Now that you are finished, you need to start chilling the wort. This is an important step because if the water is too hot, it will kill the yeast when you add it. And if the yeast is killed, all of that work was in vain!
I chill mine in the sink, surrounded by ice water. I’ll leave it in there for about an hour.
After the wort is cooled, I pour it through a sanitized (REMEMBER: SANITIZE EVERYTHING!) strainer and into my brewing bucket. The brewing bucket has approximately 2 gallons of ice water. This further helps cool the wort.
You can see the strainer catches a lot of hops that escaped from the bag.
Once the wort is sufficiently cooled, pitch (add) your yeast, cover and put in a controlled environment for at least 2 weeks (or longer depending on the style).
I’ve done quite a few of these. The total time for me from start to finish is approximately 3 1/2 hours. So when you brew be prepared to set aside a large block of time.
Numbers 28.7: “Its drink offering shall be a quarter of a hin for each lamb. In the Holy Place you shall pour out a drink offering of strong drink to the LORD.”