We recently read about an interesting brewing method and a pretty enlightening experiment, which we discovered on the Brulosophy website: overnight mashing. It's exactly what it sounds like. Start a batch of beer one day (generally late in the evening) and finish it the next day. Before we get into how it impacted the beer, here's how it's done:

Overnight Mashing Process

1. Heat water to strike temp

2. Grind and add in grains

3. Wait for temp to stabilize (if you're using our digital controller)

4. Turn off heat and leave grains sit overnight*

5. Resume brewing next day

*We installed one of our insulation kits on the kettle, which helped maintain a mash temp near our original target for the length of time that the grains would have been converting. This allowed us to turn off the element. However, we could have (and considered) just leaving it on, set to the mash target temp.

Overnight Mash Brew Video

Here's the overnight mash brew day video. Keep scrolling for more detailed information on the process.

Overnight Mashing Advantages

1. The process saved a bit of time by allowing us to mash in and then leave, without having to wait around 60 minutes for the boil to finish.

2. It also allowed us to break up what is normally a 6 hour brew day into two shorter chunks. This also has it's advantages.

3. The beer tasted pretty much like any other beer (of the same style) we've made. 

The folks over at Brulosophy also brewed an additional batch of the same beer but didn't mash overnight (they brewed it normally). The two finished beers were served to a group of taste testers who were unable, for the most part, to tell the the two different beers apart.

That said, the beer we brewed was a single hop session IPA and we were not happy with the hop selection (More on that below). So we may try this process again with a recipe that we're more familiar with and we know we like.

Overnight IPA Recipe Details

Water

Beginning water volume: 7.83 gallons (29.6 liters)

Our brewing kettles have gallon markers on the inside so you can monitor liquid volumes throughout the brew day

We adjusted the water chemistry to produce the following profile:

• Calcium: 100ppm
• Chloride: 136ppm
• Sulfates: 75ppm
• Sodium: 14ppm
• Magnesium: 6ppm
• Bicarbonates: 25ppm

Note: we also added half a campden tablet at the start of the brew day.

Campden tablets are used to remove chlorine and chloramine from water

Malts

• Pilsner (2 row), German - 6lbs. (2.7 kg) (65.2%)
• Barley, Flaked - 12.8oz. (363 grams) (8.7%)
• Oats, Flaked  - 12.8oz. (363 grams) (8.7%)
• Rye, Flaked  - 12.8oz. (363 grams) (8.7%)
• Wheat, flaked 12.8oz (363 grams) (8.7%)

Getting all of our malts ready

We mashed in at 152F (66.7C), let the temp stabilize with the element on (with the controller set to 152F - 66.7C), then turned the element off and let the kettle sit for 12 hours, as mentioned above.

Mashing in for our overnight mash

Boil Hops

We didn't add any hops during the boil but we did a hop stand of 2oz (56.7 g) of Chinook once the wort had chilled to about 180F (82.2C).

We recirculated through the hop silo during our hop stand to ensure all of our wort came in contact with our hops

We let these chill for about 20 minutes while the wort continued to chill down to yeast pitching temp.

Fermentation

We used one package of London Ale 3 (#1318) from Wyeast and fermented at 66 degrees Fahrenheit (18.9C) for 7 days.

Dry Hops

We dry hopped this beer with 3oz (85 grams) of Chinook for 3 days. We then hopped with an additional 2 ounces (56.7 grams) of chinook once it was in the keg. Then gave it one last dose of hops by dry hopping with 2oz. (56.7 grams) of Amarillo for 5 days. See the tasting section below for an explanation. 

Benchmarks

• Post-boil gravity - Actual: 1.047
• Volume into the fermenter - 4.9 gallons (18.5 liters)
• Final Gravity 1.011
• ABV - 4.73%
• IBUs - 30

We often use a sanitized turkey baster to take a gravity sample

Tasting Notes / Rating

The reason we're doing these single hop beers is to get a real sense for what the individual hops taste like. Chinook tastes weird. That's what we gathered from this one! It has a grassy, mellon like taste - almost like a muscadine grape. The grass notes could have come from the hops or our process. We aren't quite sure. Nevertheless, it' didn't work in this beer.

Our first solution to rectify the problem was to add more Chinook. Not sure why we thought that would help. It didn't. We then added a couple ounces of Amarillo and let them sit for an entire week. It finally did the trick and we were able to salvage this batch.

All in all, we'd rate the early version of this recipe as a 5 of 10. Adding the Amarillo bumps it up to a 6 of 10. Drinkable and even enjoyable, but not awesome.