There was a question on the Build Me A Brewery Facebook page asking about “A Pro-Brewers Brewing Day”. The exact wording was, “does anybody have examples of what a ‘Pro Brewers’ brew days looks like, in regards to checking wort pH throughout etc.”

Well, I always say, if one person asks a question, then there’s at least one other person who also wants to know. So, I thought why not write an article…
One reason not too, is there’s lots to consider. Be warned this may become a mammoth article. So, let’s buckle up and see where we end up.
A Pro-Brewers Brewing Day – Long Term Planning
Before we even get to the brew day. There’s a lot of prior preparation and planning. Brewers working in commercial brewery’s’ of any size, will have a one-month schedule, as well as a weekly schedule.
In brewing nothing happens in isolation. A typical brew has several stages:
1. Brew-day – Where we make wort (malt sugars), which will turn into alcohol
2. Collection to FV and yeast pitch – If kettle souring, wort maybe held in the kettle for 12 – 72 hours.
3. Fermentation – Usually takes 5 to 12 days depending on the yeast and beer style. For our dedicated article on fermentation please click here.
4. Maturation – The beer will mature, mellow with sediment and yeast dropping out.
5. Clarification – Not all beers should be clear, it depends on style and recipe.
6. Carbonation check and lab analysis – Make sure the beer is good to package.
7. Packaging – The beer is then then packed, typically in to can, bottle or keg.
8. Deliveries – The beer is delivered to the customer.

Making Beer Isn’t Easy
As you see making beer isn’t simple. A brewer has to plan, to ensure there’s sufficient stock of all the beers in the range. So, according to predicted sales and beer inventory; a monthly production schedule is put together.
In the plan, all processes for every beer are accounted for. The plan usually has some in-built flexibility, as beer can be unpredictable. Whatever happens, brew days are scheduled weeks in advance.
So, as you can see there’s logistics and planning, way before you get to the brew day. These plans include having the necessary raw materials for all the brews in stock.
A Pro-Brewers Brewing Day – Preparation the Day Before (or days before)
The day before you brew there’s some preparation for the brew planned the next day. What you do depends on the brewery, raw materials used and brewhouse design.
Here are the main considerations of most brewers:
Yeast – If your using wet yeast, then you need to make sure it’s ready for pitching the next day. To prepare wet yeast ready for pitching can take several days. To ensure the yeast is ready, make sure it planned in your production schedule.
Hot water – Make sure the water is hot enough to mash in the next day. You either heat up the water the day before, or you have a hot liquor tank (HLT) with a timer. Ideally you want the water hot enough to mash in, as soon as possible.
Cold water – If you’re using a cold water tank (CLT) (chilled by your glycol/alcohol system), it must be chilled ready for the brew day.
Malt – If you’ve a malt delivery system with grist case, you can mill the malt the day before. Most smaller scale craft brewers mill the malt the day before. If you don’t have a grist case then mill the malt back into the bags they came out of.
FV/Unitank – You know which tank you’ll be brewing into. If it’s still full, it’s priority to empty and have it cleaned; ready for wort collection. Which leads into communication
Communication – If you work as part of a brewing team, everyone should know what the plan is for the next day. For me as a head brewer, I make sure everyone has a copy of the production schedule.
Plus, I make sure everyone is aware of the plan for the next day. I usually have a whiteboard somewhere in the production area with a weekly plan, which can be updated if plans need to be changed.

Extra note:
If the tank you’re going into has been empty and unused for more than 72 hours. I like to give it a quick re-fresh with an acid clean prior to filling.
Furthermore, the day before brewing, I usually print out a copy of the brew sheet. I like to have a physical copy to fill in on brew day and make notes.
If you feel the need to refresh yourself with the steps of the brewing process, then click here to read our dedicated article.
A Pro-Brewers Brewing Day – Prior to Mashing In…
The priority of any brew day is getting mashed in for me. There is though some prep work to prior to mashing in.
Water profile – Different beer styles require different brewing salts. The information regarding which and how much salts to use, should be on the brew sheet. These salts need to be prepared.
Water temp/pH – Check your water is temperature good. If your using steam in your brewery, make sure the generator(s) is on. In some breweries, they check pH of the water in the HLT.
I don’t recommend adding acid to treat water in the HLT, although some brewers use this method. I prefer to use acidulated malt of lactic acid in the mash/kettle/FV where needed.
Malt – Make sure you malt is ready to go. A quick brewers tip, always start and end milling with some base malt. It means there’s no chance of specialist malts being left over in the system for the next brew.
You don’t want to have some black malt left in an auger/mill from a stout brew, going into a hefeweizen, if it’s the next brew planned.

Pre-heating the mash tun – Most brewers will run some hot water thought the CIP spray ball to pre-heat the mash tun. Pre-heating the mash tun makes it easier to hit your target mash temp year-round. Also, it doesn’t hurt to give the mash tun a quick rinse.
Mashing in Your Brew – A Pro-Brewers Brewing Day
The key elements to any mash are:
Water volume – Most brewers will go with 2.5 to 3 liters of water for every kilogram of malt. For example, if you’re using 300kg of malt, you’ll use 750 to 900 liters of water.
Mash pH – Having the right mash pH is important to your beer. It’ll improve the taste and stability of the beer plus, efficiency of the brew. The mash pH is merely the pH of the mixture of the water and grains in the mash.
Mash Temperature – The temperature of your mash can really affect the finished beer. For example, if you want more residual sugar left in your beer. Then mash in at a higher temperature say 69°C (156.2°F).
If you have steam and looking to step-mash, you’ll start with a lower mash temperature and heat up the mash during the mash stand.
Depending on your brew system, you’ll either add all the water first and then mix in the malt after. If adding all the water first, brewers tend to also add and mix in the brewing salts (and any acid) at this time too.
On bigger systems with a malt delivery system, you’ll pre-mix the water and grain using a grist hydrator as it enters the mash tun.

Even in these bigger systems you’ll add a small percentage of the mash water volume before adding any malt. It’ll helps with mixing. In most systems, the brewing salts (and acid addition) are added manually into the mash at various time during mashing in.
For example, add some salts and acid in the water before malt. Then add some in the middle and the last bit, towards the end of the mash. It leads to a better homogenous mix of the salts (and acid) within the mash bed.
The Mash Stand – A Pro-Brewers Brewing Day
In most breweries the “mashing in” takes between 10 and 25 minutes. Make sure you’ve no dry malt or clumps where possible. Then the mash stand begins; most breweries have a one-hour mash stand minimum.
I leave the mash for five minutes, before taking a sample to check the pH of the mash. As we said before; the pH of the mash in very important. With some systems you might need to recirculate the wort to get a true sample, which represent the proper mash pH.
Target Mash pH
Depending on beer style, the target mash pH should be between 5.2 and 5.5. If it’s too high you can add some acid, usually phosphoric or lactic.
If it’s too low then you can add some baking soda. Darker malts will make the mash pH lower. So, you’ll add less acidulated malt or acid.
If you do need to add to the mash once the stand has begun. You’ll need to make sure any additions have been thoroughly mixed in. Extra additions to the mash aren’t ideal so, it’s advisable to extend the mash stand, if you need to thoroughly mix in some extra additions.
Big ABV Brews
If you’ve done a big brew such as an imperial stout with a large grain bill, increasing the mash stand to a minimum of 90 minutes is advisable. The easiest way for most brewers to check all the sugars have been converted from starch is an iodine test.
In the presence of starch, the iodine turns purple/black. Therefore, a test on a sample of wort taken from your mash will let you know if the enzymes in the mash have done their job. Or, if you need a longer mash stand.
Once the conversion is complete you can begin the vorlauf/recirculation of the mash. If using a 4-vessel system once the conversion/mash stand is over, the mash is transferred to the lauter tun.
After the transfer of the mash to the lauter is successful, most brewers will also incorporate a “lauter stand” in to the process. It is usually 10 and 20 minutes long.
Vorlauf/Recirculation of the Mash – A Pro-Brewers Brewing Day
Vorlauf is when the wort in the mash or lauter recirculated. The wort is taken from under the false bottom of the lauter tun then recirculated onto the top of the mash bed.
The mash bed acts like a filter allowing the wort to become clear, before it’s sent to the brew kettle. The vorlauf is usually a minimum of 10-minutes long. Most brewhouse have a sight glass to allow a brewer to easily check the clarity of the wort.

Collecting Data Points
During the vorlauf it’s a good time to recheck wort pH and also take a gravity of the “first runnings”. At Asian Beer Network, we always advise collecting as much data throughout the brew day as possible.
Overtime the more historical data you have, the easier to gauge whether a brew is on track. Furthermore, if there are issues with the beer later on, data recorded on the brew sheet may allow you to figure out where the issue came arose.
Once the wort is clear, with all the starches converted and a sample of the wort checked for gravity and pH (plus recorded). The wort is ready to collect to the brew kettle.
If you have a steam jacket on the mash tun, you can raise the temperature of the mash before wort collection or transfer to the lauter. It’s called the “mash out”, with temperature of the mash set to 77-78°C (170 to 175°F)
A Pro-Brewers Brewing Day Part 1 – Conclusions
Thanks for reading part of our article on a pro-brewers brewing day. In the next part we’ll pick start with the wort collection to the kettle. I know this would be a dense subject to cover.
So, splitting it into two parts makes sense.
The main takeaways so far are:
pH of mash is critical – Your target pH range for most beer styles is pH 5.2 to 5.5
Don’t let the mash bed get too hot – Or you’ll start to extract bitter tannins
Take notes – Record data on a physical brew sheet, you’ll learn a lot about your brewhouse and lead to more consistent beer
Clear wort – Make sure you’re not carrying malt to the brew kettle
Iodine test – Make sure the starch in the mash has been fully converted
Start and end with base malt when milling – So not dark malts are left in the mill for the next brew
Always plan ahead – You’ll be more efficient and the whole team will know the tasks for the day.
I know I’ve missed some stuff out. So, please feel free to add your own observations, practices or tips below in the comments section below. Also, if you’ve some feedback or follow-up questions, please feel free to email at:
Or scan the QR code of your preferred network below, add me and message me there directly. Thanks for reading and I hope you picked up some nuggets along the way.
When part two of a pro-brewers brewing day is ready we link here, it should be ready soon.
Cheers and happy brewing
Neil
