This is the fourth and final part of my four part series on improving beer clarity. In the previous sections we discussed how to measure clarity, causes of poor clarity, proteins and tannins and how to control and improve beer clarity in the mash and the boil. Today we’re going to discuss fermentation finings and filtering your beer to improve clarity and reduce beer haze.
Lagering and Cold Crashing during Fermentation
When fermentation is complete, you may want to consider cold storing or cold crashing your beer. Lowering the temperature to near freezing will aid the precipitation of yeast, proteins and polyphenols. Also storing your beer cold is a great way to prepare it for filtering if desired.
Note that cold crashing (rapidly chilling the beer to near freezing) will kill off any remaining yeast, so you should not use this technique if bottling unless you are planning to pitch additional yeast when bottling. If you cold crash a beer before bottling and don’t add additional yeast to aid in carbonation you will get flat beer. Similarly you don’t want to cold crash right after bottling, as your beer needs time to carbonate.
Fermentation Finings
A number of finings can also be used during fermentation. Most are added at the end of fermentation, a few days before bottling or kegging. This allows fermentation to complete, but gives the finings time to work and settle out some particulates.
- Gelatin – Available in the “jello” section of the grocery store – in ‘unflavored’ packets. Prepare on packet in a pint of hot water, and then add it to your 5 gal (19 liter) batch a few days before bottling. Works on both proteins and tannins.
- Polyclar (PVPP) plastic – Polyclar is a polymer based powder that takes on a positive charge, and is effective at removing proteins, tannins and yeast. You can purchase it from most homebrew shops and should be used at a rate of about 1 tablespoon per 5 gallons (19 liters).
- Silica Gels – Includes a number of new brand name products. These gels are effective at binding proteins in particular, though they can affect flavor and foam retention if used in excess. These are added at a rate of 5-10 grams per 5 gal (19 liter) batch.
- Isinglass – A thin – fiberglass like substance that is derived from fish bladders and has been used for a long time in brewing. It is effective for removing yeast cells and proteins, and also removes some lipids which can actually improve foam stability. Some people who have very strong allergies to shellfish can have a reaction to this substance though, so some care must be taken.
- Papain – Used more extensively in wine making, this is one of the first finings used commercially for clarity. It has fallen out of use by most professional brewers, however, as it has a negative impact on foam stability.
Filtering Your Beer
Obviously commercial breweries cannot afford to have their beer sitting for weeks and months while waiting for it to clear. Instead they often use filtration to filter out unwanted yeast along with larger proteins and tannins, so the beer can be sold much more quickly. Filtering also improves flavor stability, which is important for commercial brewers who want the same flavor from start to finish.
Home brewers can filter as described here. If possible you should chill your beer first as this maximizes the effectiveness of filtering. Most home brewers use an inline filter between two kegs, and simply filter while transferring the beer from one to the other. A two stage filter works best, with the first stage being a coarse 5 micron filter to remove large particles and yeasts, and a second 0.5 micron filter to remove the smaller particles. A two stage setup like this is much less likely to clog, and maximizes the life of both filters (most filters are disposable).
Storage and Stability
Once your beer is kegged or bottled, you need to worry about storing it properly. The most important thing you can do (assuming carbonation is complete) is to cold store your beer. Cold storage will improve clarity of your finished beer and will also maintain its stability for the longest period.
In particular you want to avoid cycling your beer from warm to cold. Cycling temperatures will definitely make your clarity problems worse, and is a major contributor to both chill haze and permanent haze.
Oxygen also plays a significant role in preserving clarity and stability in your beer. Even a small amount of oxygen left in the beer will act as a catalyst for permanent haze formation. Oxygen added when transferring wort or bottling/kegging is the largest risk, so extra care must be taken to avoid splashing or adding oxygen at any point after fermentation has started.
Summary
To summarize some of the key points regarding clarity: Choose low protein malts, mash and sparge at a low pH (5.2 is ideal), don’t oversparge or disturb the grain bed when sparging. Boil for a full 90 minutes, and add a boil fining such as whilfloc. Chill your wort as quickly as possible after the boil to get a good cold break, and consider cold crashing your beer once fermentation is done. Use finings before bottling and kegging, and consider filtering your beer. Avoid introducing oxygen at all costs, and cold store your beer.
If you do all of these things you should get clean clear beer every time! Thanks for joining me on the BeerSmith Home Brewing Blog. Be sure to sign up for my newsletter or my podcast (also on itunes…and youtube…and streaming radio station) for more great tips on homebrewing. Also check out my How to Brew DVDs I shot with John Palmer on extract and all grain brewing.
I disagree on the point about pitching additional yeast for bottle conditioning a cold-crashed beer. Perhaps if you crashed it to freezing very rapidly you would have an issue, but I and other brewers haven’t had trouble. I ferment in a mini-fridge and usually chill to the upper 30s Fahrenheit for a couple days. It helps to get the bulk of yeast to settle, but my beers carb up well. I wonder how cold for how long you have to get before you lose all viable yeast?
Ok, so if you filter your beer than you have to force carbonate right? Im assuming that you would be removing all the yeast by filtering? Adding more yeast for the purpose of carbonating afterward seems like it would defeat the purpose of filtering in the first place.
Please advise.
Awesome article by the way!
“Prepare on [sic] packet in a pint of hot water, and then add it to your 5 gal (19 liter) batch a few days before bottling.”
Terribly careless recommendation.
Too much gelatin. (1 tsp is enough)
Too much water. (1/2 cup is enough)
How hot? (gelatin should no be boiled)
Should be added to bottling bucket for the best results… not the fermentor.
Great Series Brad, thank you
Do you have any pointers for removing cold break when using a plate chiller?
I’m planning on switching to a conical fermenter soon and was thinking the cold break would settle out and could just be drained off before aerating and pitching yeast.
Thank you for this great article on clarifying beer. I felt the need to respond to the comments about cold crashing of which I always do and to 33 and occasionally a bit colder, most of the beers I’ve done over this past year (about 180 gallons worth) were crashed for between 2 and 7 weeks and most were bottled and in 14 years of brewing have never added yeast at bottling without any problems whatsoever. My beers are clear and well carbonated every time.
David
From my experience, cold conditioning ales to 35F does not kill the yeast, and adding yeast for bottle conditioning is not necessary. I’ve heard some say it may take longer to carbonate, however this has not been my experience either, that holding the bottles at 75F for 2 weeks is sufficient.
To say that “Cold Crashing” kills off all the yeast does not seem 100% accurate. By lowering the temperature of your fermented wort to the 30’s-40’s F your are just putting the yeast into suspension. As long as you wait 2-3 hours for your cold crashed carboy to warm up a bit on bottling day; you are still getting yeast when bottling, it may just take longer for them to come out of suspension and consume your priming sugars in the bottle.
Great insight as usual, Brad.
As far as the timing of cold crashing, should you do all your dry hopping before?
I.e., are the effects of dry hopping at all affected by temperature?
Nevermind! 🙂
Just read the dry hopping blog posts, which specifically address this.
So sorry! Feel free to delete these posts.
Here in Australia we have a commercial brewer called Coopers. They also make products for home brewers. On Coopers own brewing forum there is an article about re-culturing the yeast that is in the retail bottles of their Pale Ale, Mild Ale and Sparkling Ale products, so that it can be used as the yeast in homebrew.
These commercial ales have been sent all over Australia in temperatures that may well exceed 40C and are then chilled in refrigerators for sale. Chilling the yeast in this instance is no different to chilling he yeast in a cold-crash situation. The yeast is merely dormant and does resurrect itself when given warmth and food – the same things that homebrewers do when priming and bottle conditioning after cold-crashing.
I think that this artice is very informative but quite inaccurate about the need to add yeast when bottling. Like others have stated before me, I have cold-crashed many times and never once added yeast when bottling. I’ve never had an issue with carbonation – not even with a brew that I accidently partially froze.
I agree with David Whitwell. Cold crashing does not kill the yeast for bottle conditioning. My normal practice is primary for 1 to 2 weeks, cold crash for 1 day, let beer come back to room temp for a day ( I have found that room temp beer helps with even distribution of the sugar solution during bottling), then bottle and let stand at room temp for 2 weeks. A little tip for those who use plastic bottles. After filling your bottle, put the screw top on half way and squeeze until beer comes out and then tighten. This will remove the oxygen from the bottle and the bottle will expand back to its normal shape within a week and become nicely carbonated, if you use the right amount of sugar of course. By the way, my favorite plastic bottles are 16.9 oz root beer bottles and 2 liter pop bottles are great if you know you are going to drink at least 4 pints. Any time I use something larger than a pint, I will slowly pour into a growler, leaving the yeast sediment behind and then serve from the growler.
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