Ask Mr. Wizard

All-In-One Brewing System Advice


Ray Murphy — Cheektowaga, New York asks,

I am an all-grain brewer who has typically used a cooler mash tun. I recently bought an Anvil Foundry system, but have not brewed with it yet. Any advice for my first brew day with it? For example, things to know that might not be mentioned in the manual?


The Anvil Foundry is one of several mash-boil combination systems on the market using a removable cylinder with perforated bottom section to contain the mash. In contrast to the old school mash tun cooler design, these all-in-one (AIO) systems allow for step mashing using an electric heater element installed in the bottom of the kettle and a recirculation pump to flow heated wort onto a diffusion plate positioned above the mash. This allows uniform mash heating for step mashes as well as a handy way to prevent mash temperature from cooling during infusion mashes because, unlike coolers converted into mash tuns, these kits are not insulated (although removable insulation jackets are available).

I too switched from an old school cooler system to an AIO design two years ago and had my concerns. The biggest difference from my perspective is how wort collection is accomplished and controlled. Whether brewing small batches at home or large batches in a commercial brewery, using wort separation devices such as mash tuns, lauter tuns, Strainmasters, and mash filters, brewers can take samples of wort any time during wort collection and evaluate the color, clarity, and density. This is where AIO designs are most different than other brewing systems.

Instead of wort flowing out of one vessel, like your cooler cum mash tun, into another where sampling is easy, wort collection in AIO systems is accomplished by lifting the mash container/basket within the AIO mash tun/kettle and rotating to align support clips above a support ring. This allows wort to simply drain from the mash basket directly into the kettle. Pretty snazzy! And, just like with any other wort separation method, sparge water can be added to the top of the mash to rinse wort from the sponge-like grain bed.

In my opinion, losing the ability to take wort samples during collection is the biggest sacrifice when transitioning from mash tun brewing to AIO brewing. It’s not the end of the world, but for cranky old dudes like me who like to monitor wort clarity and, more critically, wort gravity and pH, getting used to blindly collecting wort is weird. And it also makes gravity control more challenging because there is no way to determine when it’s time to stop sparging based on wort density flowing into the kettle, the only option is to sparge with a set volume of sparge water. 

My advice for first brews on any new brewing system is to minimize the number of things to worry about. This starts with the grist bill; choose a recipe with no more than about four malt types and skip flaked adjuncts and sticky stuff like rye for a future brew. When it comes to expected grain yield, don’t shoot for the moon by fine milling; start out with a coarse grist aimed at brewing ease over efficiency. If you typically use single-temperature mashing in your mash tun cooler, use a single temperature in your new AIO system. And if you have a regular recipe that runs like clockwork, brew that beer instead of something new and different.

The one piece of advice I wish I had followed when first using my AIO system was not to sparge. I still have a hard time suggesting not to sparge because . . . well, just because, dammit, that’s how brewers do brewing! Aside from some loss of extract and brewing tradition, skipping the sparge makes hitting the wort gravity target much easier because the wort density produced during mashing is the same as the pre-boil gravity and removes uncertainty that is inherent with sparging. The easiest way to control pre-boil gravity in no-sparge brewing is by varying the ratio of water-to-malt used in the mash. To calculate the volume of water required for some target, pre-boil gravity from an all-malt mash, use the following equation:

Liquor-to-Grist Ratio (wt/wt) = 3 x 20 °Plato ÷ (Pre-Boil Gravity).

If our target pre-boil gravity is 12 °Plato (1.048 SG), for example, the equation above indicates that the ratio of water-to-grist in our mash should be 5. And if our recipe calls for 8.25 lbs. (3.75 kg) of malt, we need to use 41.25 lbs. (18.75 kg) of water in the mash.

This general rule works because most base malts and lighter colored special malts contain about 80% soluble solids, 1 part malt plus 3 parts water equates to 25% of malt by weight, and a quarter of 80% is 20% or 20 °Plato. Math validation aside, no-sparge mashing makes the target gravity a bit easier to hit. Outside of sparging, all other process steps are similar with AIO systems and your first brew should be a familiar walk in the park!

Response by Ashton Lewis.