This article brewing like a pro, is the final part of the series. For the first part “A Pro-Brewers Brewing Day” please click the link. If you’ve not read the first part, we’d recommend checking it out first.
In this part we pick up at collection of wort from the lauter tun to the brew kettle.
Irrespective on the brewhouse size, I’d advise wort collection to take a minimum of 90 minutes on most brewery systems. The goal of the lauter is to take as much wort as possible over to the kettle.
We have a mixture of wet, spent grain (looks a bit like porridge) which is full of dissolved sugars. When we collect the liquid (wort) to the kettle, we add more hot water to the top of the grain bed (sparging) to carry these dissolved sugars over.
Extended Sugar Conversion
Depending on the temperature of the mash, conversions may still be taking place breaking longer chain dextrin’s to shorter ones and more fermentable sugars.
That’s why some brewers with the capability do a mash out, do so, to control this process. When you “mash out” you raise the temperature of the mash to 77-78°C (170 to 175°F). This stops the conversion process to shorter more fermentable sugars.
If you can’t “mash out”, then you usually sparge with hot water at 77-78°C (170 to 175°F) for the same reason.
If there are too many fermentable sugars, you’ll end up with a finished beer too “thin” in body and taste. During the collection, you don’t want to temperature to go too high.
If the temperature gets too high, you’ll begin extracting tannins. It’ll make the finished beer too bitter.
Think of it like making tea with strong black tea leaves. If you let the leaves too steep for too long, it becomes very bitter. It’s similar, if the mash bed temperature gets too high, your finished beer will be too bitter.
Other Lauter Considerations – Brewing Like a Pro
pH is important when lautering too. The pH of the sparge water is going to be higher than the pH of the mash bed. Therefore, the pH will increase during the collection to the kettle. Your final running’s will have a higher pH than first running’s pH.
As the pH of the running’s increases, you’ll extract more tannins. The running’s pH should never rise above pH 6.0 during collection. Ideally, you’ll finish collection with running’s at 5.8 pH.
If the pH goes too high; stop the collection immediately as you’ll be carrying across too many tannins to the kettle. It’s the same with the gravity of the final running’s too.
Go too low and you’ll also carry across too many tannins. The point where you stop wort collection, comes with experience of the system over time. If you unsure take a sample checking both pH and gravity of the running’s.
For example, a beer of 1.040 SG (10 Plato) original gravity, you can stop collection to the brew kettle in the 1.004 to 1.006 (1 to 1.5 Plato) range. This is a guide and other brewers may suggest different figures.
My Real World Example
Furthermore, during collection keep an eye on the level of the mash bed and ensure the collected wort is clean. You don’t want to carry malt over with the wort.
I know this is a lot of information to take in, but with time and experience it’ll become second nature. I’ve learnt to understand brewhouse systems during my 25-year brewing career.
For example, I recently took over brewing operations of a 2,500-liter brewhouse. When I oversaw the first few brews, I saw some issues…
The final running’s of the wort was too low in gravity, and too high in pH. Plus, the amount of sparge water the brew team was using was way too much.
It took me a few brews to make some changes to the SOP (standard operation procedure) of collection to the kettle. The new process I implemented, was to use the rakes for a few revolutions per 15 minutes of lauter time.
We now use the rakes roughly 5 times during the sparge. This allows for better run off efficiency. The results of the changes meant we could use the less sparge water, with the last running’s pH and gravity improved. Overall, the brewhouse efficiency went up by 5%.
If we used the rakes too often, it affected the wort clarity and we’d start carrying malt to the kettle with the wort. It took a few brews but we finally had a process we liked.
Furthermore, we also had to reprogram the VDF controls for the lauter rakes, to make them slower too. If the rakes move too fast, then the same issue of malt going to the brew kettle happens.
Bringing the Wort to a Boil – Brewing like a Pro
When collecting wort to the kettle, you can also begin heating the wort too. You don’t want the wort to boil before the collection is finished. However, holding it as around 90°C (194°F) is fine.
It means once the collection is finished, you’ll not have wait too long for the wort to get to the boil. Also make sure you to do a final running’s pH and gravity, recording the data on the brew sheet.
Likewise, if there were any issues during the run-off, make sure to record this on the brew sheet as well. All brew sheets should have a comments/note section.
First Wort Hops
Also, some brewers making hoppy beers or lagers, like to do a “First Wort Hop” (FWH) additions. This is when the hops are put in the kettle before the collection of the wort has begun. It can be a portion of the bittering addition or all of it.
There’s no clear evidence it can help improve a beer’s quality. However, some brewers believe it leads to smoother bitterness and better aromas. I don’t first wort hop, myself. I actually prefer to use a CO2 hop extract for my bittering additions.
When you have collected all the wort you can take a gravity reading, if it’s too high then you can add some more water. If it’s too low then you might want to add some sugar, LME (liquid malt extract), DME (dry malt extract) or boil for longer.
There are reasons for choosing one option over the other. I’ll cover this in another article, as this article is going to be a long one as it is.
One of my main criteria for any brew day is to hit my target gravity AND be in the desired pH range before collecting wort to the fermentation vessel.
In fact, the project I did last year helping Humdinger brewery commission, install and get a 2,000-liter brewery operational. David the client said “the fact hitting target gravity is a non-negotiable for you Neil, was one of my biggest takeaways”.
Notes from the Boil – Brewing like a Pro
Ok so we’ve collected the wort, we know the volume of the wort in the kettle. Furthermore, we know the pre-boil gravity and pH. This information helps us determine several factors of the boil.
The Length of the Boil
If the gravity was too low, the boil time can be extended to reach the target post boil gravity. If the boil is to be extended beyond a 60-minute boil, we can wait to add the bittering hop addition.
Hop Additions
As part of the recipe, we’ve calculated the hop additions for both bitterness and aroma. If for any reason the volume collected is too high it too low, we should recalculate those hop additions.
Boil pH
Knowing the pre-boil pH; gives us an idea of what the post boil pH will be. We’ll still measure the post boil pH as it’s a critical data point. Ideally post boil pH should be between 5.0 to 5.2 pH.
It depends on style but landing in this range helps extract the best character from the hops, maximizes your hop break and keeps color pickup to a minimum.
We discuss more regarding the importance of post boil pH in our kettle boiling tips article, which you can read by clicking here. Generally, though, if you’ve hit your mash pH, you’ll hit the right post boil pH too.
Post Boil Volume
If you know your pre-boil volume, your pre-boil gravity and post boil gravity then you can figure out your post-boil volume:
(Pre-Boil Gravity / Post-Boil Gravity) * Pre-Boil Volume = Post-Boil Gravity
For those who don’t have a flowmeter for collection to FV, this is a nice figure to have. However, please note, you lose some wort left behind in the kettle after collection.
Furthermore, you’ll lose some volume when the wort is cooled by the heat exchanger on the way to your FV. Liquid contract when it becomes colder.
Brewing like a Pro – Further Boiling and Whirlpool Notes
As we said earlier, we have a whole article dedicated to the boil. However here are a few other key issues to note during the boil:
Sterilization – When you boil wort you sterilize it. Boiling wort is necessary to ensure it’s contaminant free.
Increasing bitterness – Adding hops to the boil will increase the beer’s bitterness.
Strong vigorous boil – You want a good boil, ideally 3 to 10% evaporation rate per hour. A strong boil also helps to boil-off volatiles. It’s also helps with the “hot break” too.
Stop the trub – It’s better for your final beer if the hot break isn’t carried over to the FV. In modern breweries a whirlpool is used to separate the trub from the liquid wort.
In the hot break are proteins and nitrogen constituents which interact with carbohydrates and polyphenols.
Whirlpool hop additions – Brewers like to chill the wort down to 80 – 82°C before adding their whirlpool hops. It allows for more hop oils to stay in the beer.
There are some brewers who like to drop the temperature lower to 71 to 76°C (160°F to 169°F), some even go as low as 66°C (159°F). It’s a brewer’s preference and up to their discretion.
Like with most of the stages of brewing we’ve gone through so far, there’s a lot to take in. Again, you’ll pick this all up, when you gain more experience.
Collection the FV and Wort Aeration
We’re nearly there now, the yeast used will determine the collection temperature of the wort. You’ve done your whirlpool and confident you’ve got a nice tight hop/trub cone.
Now it’s time to collect the wort to the FV. We’ll cool the wort to the fermentation temperature and aerate it on the way to the FV. Yeast and oxygen need each other.
If you’re using dried yeast from Fermentis, they say you don’t need to oxygenate your wort. However, if you plan to re-pitch the yeast later, then it’s recommended to aerate the wort.
Some beers I don’t aerate. For example, if I’m making a wheat beer with Fermentis WB-06, I don’t oxygenate the yeast. As WB-06 is a Diastaticus yeast, and seems to produce better finished beer, if it’s brewed under harsher conditions.
The ideal range for adding O2, is to achieve 8 to 10 parts per million (ppm) dissolved oxygen. Remember colder wort will naturally pickup more oxygen.
When collecting the wort to FV, you want to keep the temperature as constant as possible. Once the temperature has stabilized and you’ve got at least 10% of the wort collected, you can begin pitching the yeast.
Pitching Yeast – Brewing like a Pro
These days with dried yeast, you can simply sprinkle it in to the wort, as it filling is filling. However, this isn’t rue of all dried yeast, so please follow the directions provided by the yeast manufacturer.
If I’m using wet yeast, I like to pitch from cone to cone where possible. This can be planned and put into your production schedule.
If the yeast has been propped, then I like to push the yeast over in-line with CO2 during the transfer of wort from kettle to FV. It’s the same with yeast being added from a yeast brink, I like to add it in-line, during the transfer.
Finished Up the Collection – Brewing like a Pro
When you pump wort from the kettle to the FV, there is always some left in the line which the pump can’t transfer. I either push this wort across with hot water, or push it with O2.
It depends on your brewhouse system and brewer’s preference. I always have a sight glass just before the butterfly valve at the bottom of the FV. When the last bit of wort has been collected, I can stop the transfer.
Once, the collection is finished, it’s time to square everything away, and begin the clean-up. One of the last actions is to put a see-through pipe onto the CO2 inlet of the FV, which goes into a bucket of water with some sanitizer in it.
This is to make, the FV’s a closed circuit. Of course, if you using an open-top-vessel, you can’t do this. I simple like to have a closed system for my beers in tank where possible, to stop the possibility of anything getting into my fermentation.
Also, when the fermentation starts, you’ll see bubbles in the sanitizer in the bucket. It’s nice to have this visual cue when you’re brewing.
Especially when brewing lager, when the yeast has a longer lag phase.
Brewing like a Pro – Conclusions
There you have it, sorry this turned into an epic article. I warned you at the start and I kind of knew this would happen. I did actually enjoy writing this article, it was good to go through the process in my head how brewing like a pro .
I’ve missed some stuff out, I know. 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.
Cheers and happy brewing
Neil
