Process

Reducing Process Time (Cellar)

Here is my tried and true method for 14-day turnarounds (sometimes way less!) for everything except lagers:

*Source: I am a former Senior Brewer, former Head of Cellar and former Sr NPD at BrewDog, former Director of Production and Operations at Magic Rock Brewing, current Director of Technical Solutions at YCH Hops.

1) (Day 1) Wort nutrition and YEAST HEALTH

Your yeast must be healthy going in. Not just viable, but healthy. Ensure that your wort always has enough oxygen, ergosterol, medium chain fatty acids (MCFAs) zinc, amino acids and vitamins for the mother cells to produce healthy daughters and for all cells to have healthy membranes and intracellular reserves after fermentation has finished. For a 50hl batch, using British malt (low FAN compared to German and EEU and US malt) I found the sweet spot to be the following:

• 20gm ZnSO4(7H20) for a total Zn2 supplementation of 2.5ppm
• 10kg medium thick spent yeast slurry (at ~30% solids) for MCFA, ergosterol and B vitamins.
• 333gm 2:1:1 BCAA mix of Leucine, Isoleucine and Valine (to reduce alpha-acetolactate synthesis)

Oxygen to 12ppm for <8% beers, 15ppm for 8-10% beers and lagers, up to 20ppm for stupidly big beers. For multiple batches into 1 FV, oxygenation is volume and time dependent: For 2 batches, oxygenate both the same, for 3-5 batches in under 24 hours, first 3 batches at 1x regular O2 levels (e.g. 12ppm) if doing 3, but if doing more, divide the O2 up among the first 3 batches then stop. Example: For 4 <8% brews, oxygenate the first 3 at 1.33x regular rate, or 16ppm. For 5 <8% brews, you could either add O2 normally to the first batch, and then supercharge the next two, or do 1.5x, 1.5x then 2x. For 5-10 batches it gets tricky. You can either add the total O2 required for the final total wort volume in the first 50% of brews, but you’ll lose a lot when it breaks out of solution into the headspace. A way around this is to oxygenate the first batch at regular level, then gradually increase the volume of O2 going into subsequent batches until you hit the total volume required. The theory being that the hydrostatic pressure and existing volume in the tank will provide enough back pressure and liquid volume for the O2 to dissolve into solution. I would never add oxygen after 20 hours for fear of flavour impact.

Pitch 1 million live cells per ml per degree Plato of TOTAL WORT VOLUME (into the first batch if doing multiples) for <8% beer, 1.25-1.5 million/ml/degree P for bigger beers and lagers, up to 2million/ml for really big beers.

Enough calcium for good flocculation.

Ramp up your nutrient management by getting wort analyses done and you can fine tune this further.

2) TEMPERATURE MANAGEMENT:

Manage your temperatures carefully. This is strain dependent, but as an example for WLP001/1056/US05 and many of the common strains:

• (Day 1) Pitch cold (17C for ales fermenting at 18C, 8C for lagers fermenting at 10C).
• (Day 2-3) At 50% attenuation, let the beer rise to 23C (for ales, for lagers go to 15-16C, Saisons… I’ve gone as high as 28C) and finish out. For anything over 7% ABV I tend to wait until 70% of attenuation so as not to create too many estery and phenolic notes.
• (Day 3-5) Once FG has stabilized and the pH has risen, put on 0.2barg of top pressure with inert gas, open the cooling on the top jacket(s) and drop the temp by 5C.
• As soon as the vessel is at 18C, turn off the top cooling and open the cooling to the Cone for at MOST 8 hours.
• (Day 4-6) Keep your top pressure on, and harvest and dump your yeast and take a sample for VDK testing (we used the forced diacetyl method until we got GC). The yeast in the cone isn’t doing anything for diacetyl reuptake, and there will still be plenty in suspension. If you’re worried, do a cell count.

​​3) (Day 4-7) DRYHOPPING, or recirculation is king (18C):

Setup: I had tanks specially made with tangential inlets at various points up the cylinder, but you can also recirculate by coming out of the total outlet and going up a stand pipe or movable racking arm. If the latter, angle the racking arm to about 135-150 degrees off horizontal. For regular T90s, I recommend beginning the recirculation in reverse, to mix the hops into suspension and prevent clogging your pump. Reversible or Star/Delta pumps are amazing for this. This isn’t as big an issue for Cryo. Anyway, get the pump spinning your beer.

• Release the top pressure on your tank and get your hops in using your normal method. As anoxic as possible, and get the inert top pressure back on your tanks.
• Let the pellets dissolve (takes about an hour for regular T90s, minutes for Cryo), then switch your recirculation back so it’s coming out of the total outlet and in the riser/racking arm/recirc ports. If you have to move hoses, and switch ports, use valved Ts in this situation so you can clean the set up in place and manoeuvre the setup hygienically.
• Recirculate your tank to keep the hops in suspension for 12 hours. You will see a temperature rise of about 2C. This is a good thing for hop oil absorption, yeast final fermentation and diacetyl uptake. We saw no positive flavour development after 12 hours, and tried recirculations (constant and staggered) all the way up to 48 hours. This method was tested against standard dryhopping (dumping in and let settle), and dump & bump roused dry hops.
• Shut off the pump, turn your cooling back on to bring the tank down to 18C, and let the hops settle (8-12 hours).

4) (Days 4-14) CONDITIONING AND MATURATION:

Begin dumping your hops – dump as long as its fairly thick and you’re not wasting too much beer. Take your final VDK test. If it passes, continue on, if not, you may want to give it a wee bump with CO2 or other inert gas through the riser or racking arm.

Cool as you like. I’ve found no real benefit from staggering cooling for standard dryhopped ales, so I crash it straight to -1C after VDK pass if my cooling system can deal with it. YMMV. For best results, use the top jacket(s) until it hits the inversion state at 5C, then open them all. Its crucial that you keep your top pressure on during this phase to prevent sucking in air. If you’re using CO2 as a top gas, you’ll also get some nice carbonation developing. (If using finings, don’t cool past 6C until you’ve dosed them in and they had time to work.)

Continue gradually removing the hops twice a day until you’re ready to spin/filter/fine/transfer.

5) EQUIPMENT & TRICKS

Some things that can speed up your day:

• Inline carbonation can save many hours/days over top pressure and carbstones.
• Separators are great, but expensive. It may be worth it for yields and time savings. Do the ROI.
• Quick, sacrificial 5-10 second blasts of 2%NaOH spaced about 5-10 minutes apart can really get rid of the caked on krauesen in your tank faster than a regular caustic cycle. Start your CIP cycle with some caustic shots, then go on to your normal routine and you can sometimes shave 30 minutes or more off of a cleaning cycle.
• Hot Caustic (85C, 2% NaOH for 30 min), Rinse, ATP, PAA at appropriate level works just fine. You can use phosphoric if you want.
• You only need to clean a vessel if there is messy soiling. If your BBTs only held finished beer, you can easily get away with a low DO rinse (De-aerated liquor or water hotter than 82C) and sanitization via chemicals or temperature (hot DAL/water). This reduces cleaning time and consumption, and also reduces the amount of time spent purging the gas from the vessels and pressurizing them.
• Purge vessels from the bottom in bursts. This is vastly more time and gas efficient than a gradual purge over time, due to the inevitable mixing caused by the convection currents created by the incoming purge gas. Read up on the ideal gas law to understand why. Pressurize up to 0.5bar with CO2, then release all the pressure from the top outlet. WARNING: This is VERY loud. At minimum, everyone needs ear protection, and even better to have a sound muffler you can connect to the top outlet line. Takes about 3 blasts and dumps to get a 160bbl BBT to <15ppb O2 at the sprayball/top outlet, then a gentle pressurization up the bottom to 0.5bar brings it down below 7ppb (the lower resolution of the units we use to test this).
• Audit your process flow speeds. Look for delays and pinchpoints/bottlenecks. Some common ones I see are beer being held up in tank because it was taking too long to de-hop or de yeast. Installing a spent yeast tank and using pumps can really speed this up. As an example, we modified our waste setup so we could dump all the hops and trub down the drains into our sump, then the sump pumped over a run-down screen that filtered out solids, separating the liquid stream into the pH balancing and fine solids settling tank, and the solids slid down into skips. This saved a LOT of time for cellar peeps and also reduced manual handling. Another common issue is being unable to cool fast enough… maybe upgrade your chiller or change the glycol temperature? Packaging was slower than cellar capability… maybe another set of hands or another kegger would help you empty your tanks faster? Hell, the placement of raw material storage is a factor. Track how long it takes to walk over to your hop storage and get the hops, bring them back and add them to the tank for dryhopping. Consider pack size changes!