BIAB like a BOSS - Beer, Wine, Mead, & Cider Brewing Discussion Community.

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I began my home-brewing career a little over a year ago and have to admit, I am completely hooked on the art and science of the craft. I am fortunate in that an ex-roommate of mine some years back was a keen brewer, allowing me to assist and enjoy the fruits of his labors. This provided me with some insight into the process prior to embarking on my own journey of discovery. Luckily, it was relatively early in the learning process that I discovered HBT and to say this forum is invaluable as a resource is no small exaggeration.
The purpose of this article is to outline my methods and system that I have tweaked over the last year in the hope it will assist others. I have endeavored to stick to proven methods rather than the, "it works for me so it must be OK", approach. I'm a stickler for details, so accurate measurements, calibrated instruments and a neat and tidy work area are front and center in my approach to homebrewing. Enjoy!
Planning the Brew
The planning stage has evolved from the simplicity of buying kit recipes to more recently combing the HBT recipe database, buying ingredients and tweaking things slightly to account for my own system's parameters, which I am getting dialed in with ever greater accuracy. I gravitated to all-grain brewing after two partial-mash extract-brews and recently started using BeerSmith. I am only sorry I did not purchase the software sooner. Accurate measures of grain weights, water volumes, temperatures, and appropriately calibrated instruments are essential in determining efficiencies and the dialing-in of one's equipment for future brews. If truth be told however, this is the geeky side of homebrewing which I thoroughly enjoy. The grains are milled finely using my grain-mill's narrower gap setting. With a thinner mash in full-volume, no-sparge mashing pH adjustments are also something worth considering. Other than that, no other major changes are made to a more traditional, all-grain preparation.
Preparing Strike Water
Water volume and strike temperature can be calculated based on one's system parameters, using any online calculator. BeerSmith is what I now use but have had accuracy with others too. I treat my tap-water to remove chlorine and chloramines using a carbon filter and 1/3 of a Campden tablet respectively. Water reports obtained from Ward Labs and my local water authority allow appropriate adjustments, using Bru'n Water, to be made. An accurate pH meter is arguably a prerequisite if mash acidification or alkali additions are being done.

The Mash-tun/ Kettle
As this is the only vessel I use, I concluded a quality pot with some modification was in order. An 11 gallon stainless steel kettle with holes drilled for a thermometer and valve eliminates any boil-over concerns, and allows a full volume mash for 5.5 gallon batches. To better facilitate volume measurements, quart markings were etched in the pot as described in this thread. No sparging, additional pots or water are needed. I installed both valve and thermometer using Teflon tape on all the threaded fittings and added a 90 degree elbow and barb to serve as a pick-up tube. The make-shift pick-up tube allows complete emptying of the kettle if desired. To prevent damaging the bag, a 12" stainless steel cooling rack is placed at the bottom of the kettle prior to placement of the bag and heating strike water.

The Mash
A BIAB mash should be no different in its objective than any other. I am looking for a stable mash temperature at the planned temperatures for the duration of all steps.
Doughing-in is completed while stirring constantly. I find calculators for strike temperature to be extremely accurate given accurate measures of grain temperature and mash-tun specifics. Thus far, I have been employing two-step mashes, involving a saccharification rest and mash out. Following doughing-in and temperature measurement, the lid is put on the kettle and an insulating jacket placed resulting in stable mash temperatures. Once the saccharification rest is complete an iodine test confirms complete starch conversion. The temperature is raised to 168F, while constantly stirring the mash. A mash-out rest at this temperature is carried out and then I lauter. Owing to the thin mash, and finer milling with full-volume no-sparge BIAB, mash times can be shorter than more traditional approaches. The higher water to grain ratio can also facilitate better efficiency.

The bag is freed from the pot and removed. I do not have the facility for a pulley or hoist, so allow the bag to drain in a large 16" colander paced atop the kettle. The bag is then squeezed to extract more wort. Typically, anywhere from 0.04-0.045 gallons of wort, per pound of grain is lost to absorption. The etched markings on the pot are useful here. I just keep squeezing till my preplanned pre-boil volume is reached. Donning latex gloves is of benefit during the squeeze: keeping one's hands clean and providing some minimal protection from the heat. The wort is thoroughly stirred prior to taking a representative sample. This sample is cooled to the hydrometer's calibration temperature, allowing accurate measurement of the pre-boil gravity and a calculation of mash efficiency. The steps I take result in reasonably good mash efficiencies, in the order of 90+%. The grain bag is put to one side to cool, prior to being dumped into the flowerbeds as fertilizer.

Boiling and Cooling
The boil proceeds in the same manner as any other brewing method. My kitchen stove with natural gas can easily maintain a strong rolling boil of 7 gallons facilitating a good hot-break. A hop-spider prevents much of the hop matter from entering the kettle, plate-chiller or fermenter. The wort is circulated through the chiller during the last minutes of the boil and during cooling using a stainless steel Chugger-pump with center inlet. The silicon tubing is secured with two clamps to create a whirlpool in the kettle. This augments the cooling and eliminates the risk of spilling boiling wort as it flows at speed through the tubing. For much of the year in Texas, the tap water is quite warm. A pre-chiller in an ice bucket negates this problem allowing rapid cooling of the wort to 65F and formation of a good cold-break.

Transferring Wort to Fermenter
A gravity sample is taken from the kettle and prepared as before. Once volume into the fermentor is known this gravity measurement will be used to calculate brewhouse efficiency, allowing better planning for future recipes. This data can also be used to highlight any procedural errors. The setup I outlined results in consistent brewhouse efficiencies at 80+%. The cooled wort is pumped into a sanitized carboy leaving 0.25 gallons in the kettle, chiller and tubing. The wort is oxygenated prior to being placed in the fermentation chamber where it is further cooled to the desired pitching temperature.
Pitching Yeast
If using liquid yeast, either from a fresh smack-pack or from previously harvested slurry I always use an appropriately sized starter. Once again, online calculators are a boon here. I routinely crash-cool the starter for 2-3 days and decant the spent wort. If using dry yeast I always follow the manufacturers' simple recommendations for rehydration to optimize the yeast viability upon pitching.
Fermentation Temperature Control
Arguably the most important addition to my setup is my chest freezer with STC 1000 temperature controller. This allows batches to be fermented at the optimal temperature for any given yeast and/or recipe requirement. Crash cooling is also possible. An immediate an obvious improvement in my beer was the result of this added control. I would encourage anyone with space and means to get a similar setup.

I bottled my first batch and that was enough for me. I did not enjoy the hassle. I built a two tap kegerator and just love it. It is my pride and joy. A kegerator is great for parties and still gives me a sense of satisfaction when I pull a cool beer from it. I followed an excellent YouTube video outlining the kegerator build.
Clear, sparkling, bright, delicious beer is what I am trying to brew. I cold crash and use gelatin finings in the primary fermentor with this objective in mind. I do not use secondary vessels. Clear beer can of course be achieved with bottling, without crash-cooling, without finings and with or without a secondary. This is my method, it is tried and tested by many before and is how I get the clarity I desire. The importance of getting good hot and cold breaks during boiling and chilling is however, not to be understated in the quest for clear beer.
The Results
This is what it is all about. The destination at the end of the wonderful, chemical, biological, technical and inspirational labor of love that is homebrewing. I am only beginning to scratch the surface of this craft and owe an immense debt of gratitude to all the passionate, knowledgeable, humble and humorous, power-houses of creativity, on this forum. Slainte!

I love to see step by step of people's process as I have just purchased a 10 gallon pot and have ordered my bag after many extract batches. Next week will be my first attempt at all grain and I am pumped!! Thank you for the info!
A few things:
>.Typically, anywhere from 0.04-0.045 gallons of wort, per pound of grain is lost to absorption.
That hasn't been my experience. I'd put water loss at 0.06 - 0.1 gallons per pound, even with squeezing. Lately I've tried hanging the bag and letting gravity do the work for me, then give a few squeezes at the end.
2) I see no reason to do a mash out because once you pull out the bag - you begin raising the temperature to boiling. And pour in the drippings from the bag 15 minutes later.
3) I get good efficiency doing BIAB, because I crush tightly. But I don't routinely get > 90%. I do a dunk sparge and that helps, especially for 20+ pound grain bills, but not 90%.
To get that high an efficiency I'd think you would need to not just crush the grain but to grind it, into coarse flour.
Super well written article. I'm curious, how many pounds of grain can your 11 gallon pot handle doing full volume mash?
@ArcLight Thanks for the input. With regard to the mashout and grain absorption I found that I was getting less absorption following a mashout with the wort at higher temperatures. My mash efficiencies were correspondingly lower with the greater loss of sweet-wort. This is my primary reasoning I do one as routine. I am not sure of the accuracy of my thinking. (Small sample sizes)
My BH efficiency is in the 80's for most brews but have found a bit lower (high 70's) if using wheat or flaked adjuncts. Again I'm not sure why. My understanding of mash chemistry and kinetics is still rather lacking I fear
I'm not sure what my maximum grain bill could be with a full-volume no-sparge mash. I think 1.075 could easily be done. There is a good thread on this topic here. It might answer your question better.
Volume restrictions can also be overcome with a sparge to the desired preboil volume if mash volume needs to be reduced.
Any chance on getting a separate photo of how you hooked up your O2 stone to the tubing.. ??? I can't copy the one in the article to blow it up for details.
Thanks for sharing - I've recently gotten into water science and wish you would expound on your strike water preparation.
@ArcLight My default is around 0.08 gal/lb which seems pretty common.
Regarding maximum grain bill in full volume no sparge, it will really depend on your process and equipment as well as the recipe. The mash volume depends on your losses in full volume mashes, so you have to take into consider every loss during your process.
This picture should be what you are looking for. After losing my wand into the wort I rigged up a simple fix. A little vinyl tubing over the narrower O2 tubing a a couple of SS hose clamps to cinch things down. Works well and is easily disassembled for sanitizing/cleaning the SS wand and tubing. I like to boil the wand/stone
I needed to work out my starting point. (What's in the water?) A ward labs report was the solution here, city reports were useful too.
I also wanted to remove chlorine and chloramines. The solution: Campden tabs and a charcoal filter.
I need to know what my target mineral profile is. (Brewer decides this)
Online tools work out the required additions. Usually Calcium chloride in a solution of known concentration is all I need.
A bit of gypsum if a higher sulphate content is desired.
With full volume mashing the pH gets a bit high without any adjustment unless the grist contains darker grains. I have used lactic acid or acidulated malt. Bru'n water gives predicted mash pH and I measure the actual pH with my meter. The two results are close but not the same. More accurate adjustments are then made to any future brews' mash.
It works well. I have a Hach Pro+
I use Bru'n Water for mash and mineral adjustment calculations.
Hope this helps.
Really great article. I like how in depth it is for the BIAB method and showing awesome pics! Nicely done.
thanks for the artical Gavin!
i,l have to try BIAB one of these days, it looks like a great method for uncomplicated good beer!
great fotos by the way
Very similar to my procees. Let me ask you what you go by in getting an accurate mash temp reading? Ive started using a similar kettle recently and the built in kettle probe can read almost 10 degrees differnt from 12" dial thermometer i have.
I use a Thermapen for all my mash temperature readings. The thermometer on the pot is not accurate. Only really useful for indicating stability of a mash temp.
One thing I wanted to note is that in general I was led to believe that squeezing the bag was a no-no as you tend to increase the tannins from the grains when you squeeze the bag...
Excellent article Gavin! Since you do full volume mashing do you find it necessary to make any mash pH adjustments since your mash is thinner than those with more standard liquor to grist ratios?
With the majority of grists I do have to adjust for the increased mash pH owing to the thinner mash. Usually a few ounces of acidulated malt or the equivalent in 88% lactic acid is indicated by Bru'n water. I add little less than the suggested amounts as this gets me closer to the desired mash pH than following the exact amount predicted by the software. pH meter is useful here.
For darker grain bills it is not as much of an issue if one at all. My last brew this weekend was an oatmeal stout. Planned mash pH 5.5. Measured was 5.45 without any acid additions.. The prior brew was a Munich Helles and 5oz of acid malt brought the pH down to a 5.36 (if memory serves). Planned was 5.4
@hockeybrewer - I was where you are about 2 months ago. My very first batch I had a terrible time with temperature control. It was very frustrating trying to maintain an even 153 degrees although in the end, the beer turned out very good. Do yourself a favor and order a roll of Reflectix (?) Insulation from Home Depot and make yourself a 4 layer thick jacket for your brew pot like the one shown in the picture for this article. I also had my wife sew a "Cozy" that I put over my insulated brew pot out of a Harbor Freight padded moving blanket that cost me all of $7. My pot will now hold whatever temperature I heat it to for about 50 minutes with no more than a 1 degree drop.
I see your chiller/pump setup. I had mine like that and didn't love it, but then a friend showed me this thread and I would 100% suggest it as a great build:
Thanks for that. A really cool build. My chiller just sits in two holes in the wood. I like the easy assembly and disassembly for cleaning. A sleeker design (mine has none) would definitely be a good idea. Thanks again for the pointer.
I always thought you didn't want to squeeze any grain bags. At least this is what I thought when I do partial mash. Have I been mistaken all this time?
@ImNewToBrew Squeezing is theorized by some to release tannins if done when the wort is above 170F and the pH above a certain threshold. I squeeze the bag to extract the sweet-wort. this process seems to work well with out adverse effects on flavor that I am able to discern. The grains are never above these temperature or pH thresholds with my method as outlined. Someone more skilled as a taster may be able detect something however.
Wonderful article Gav, superbly done. The only suggestion I'd make is to shout yourself some thicker gloves for the squeeze!