Boll Weevil Brewery

Here's a familiar paradox almost every home brewer can relate to;

It's one of the finest beers you've made, a friend, who claims to be a beer aficionado is interested in trying your beer. Even though everything was perfect about the beer when you gave it to him and you carefully detailed how to pour it, you now have to explain, perhaps a little embarrassed, why the beer appeared to be so hazy and cloudy. One question I hear time and time again is, why does my beer become hazy after it has been chilled?  Believe me, this is a problem faced by almost every home brewer, regardless of brewing experience. In researching this article I was amazed at how little hard, factual or complete information was actually available on the subject of finings.

I will admit that some of the better books on home brewing have procedures, advice, and remedies but most, with the exception of Dave Millers' The Complete Handbook of Home brewing, simply state what a clarifier is supposed to do, often covering different products in different parts of the book, then leaving it to you to fill in the blanks.

Finings, it seems, are much like home brew recipes of the past, a brewer would meticulously design a recipe, then, almost as an afterthought, pick a generic package of dried "ale" or "lager" yeast without realizing how that single ingredient could make or break the quality of the beer. Lets face it, home made beer is of an incredible caliber, the quality of our beers are astonishing when you consider how "good" other amateur products can be. But the nagging problems of a hazy, cloudy beer can be a real distraction to even the best tasting brews, any experienced chef will tell you that proper visual presentation on the plate is 80% of the task of well served food. So it is with a quality beer. Brilliant clarity adds the glowing gold tones to a crisp, quenching Pilsner, the brassy-copper highlights seem to add depth and appreciation to the floral nose of a hand crafted Pale Ale, and the deep reddish shade of dry Düsseldorf style Alt really adds dimension to the overall appeal of the beer.

So what do you do about the beer your friend tried, better yet, what about that nagging chill haze that seems to invade every batch you make? In the back of your mind you know there is a way to eliminate most, if not all of that annoying cloudiness and haze. You've heard of or read the names of a seeming myriad of obscure clarifiers but they seem difficult or impossible to use. Well I'm here to tell you that your beer should look as good as it tastes. With the addition of one or two simple procedures to your normal brewing routine, such products as Isinglass, Irish Moss, Gelatin, Papian enzyme, Silica Gel, Bentonite, or Polyclar can make your beer cleaner, clearer and more enjoyable.
                                                                       
Before we get into the use of clarifiers and finings as beer additives (products that are racked off of before packaging are not actually considered additives), the natural process of wort clarification should be taken into account.

·         First, if your are mashing, a proper protein rest (120 - 124° F) will degrade haze causing proteins (by complexing with polyphenols).

·         Secondly, a strong, rolling boil of at least 45 minutes will promote a wort capable of clearing much more readily than a wort of a shorter or gentler boil.

Of the many complex reactions taking place during the boil, this article is concerned specifically with the coagulation of proteins and their interaction with simple polyphenolic (tannin) and carbohydrate based constituents that form the trub, or hot break material.

·         The basic mechanical process of a rolling boil causes these unstable proteins and gums to collide and form large enough clumps (hot break) to naturally flocculate out of solution, clarifying the wort.

·         Rapid chilling of the wort will further precipitate lower molecular weight proteins and tannin coagulum resulting in further sediment (cold break) in the fermenter or better yet, a settling tank.

·         Careful removal of both the hot and cold break material can eliminate almost half of the haze forming material in wort.

·         Secondly, if your water is soft, small amounts of gypsum (no more than 1 teaspoon per 5 gallons for this purpose) can help through natural chemical reactions involving the calcium ions.

·         Finally, haze causing proteins will naturally settle after prolonged cold storage of fermented beer. These proteins are at their limit of solubility at room temperature and come out of solution as the temperature is lowered. They coagulate when chilled and bond, forming large enough particulate to naturally settle out of solution. The magic numbers seem to be refrigeration at approximately 46° F or lower for 2½ to 3 weeks.

OK, like most brewers you've heard of or seen the fore mentioned products and perhaps even tried your hand at some, but how do you know when and how they should be used, not to mention maximize their effectiveness? Lets quickly review how they work, clarifiers 101, the positive and negative side of things: Haze causing particles stay in solution for two basic reasons;

1.      Some are so small that they cannot drop out by normal gravitational forces.

2.      The particles are of the same charge, be it positive or negative, causing them to repelling each other, not forming large enough particles to settle out themselves.

For instance, by themselves, most finings are heavy enough to settle out of solution within a few hours or days. This, in of itself in unremarkable, what makes these finings effective are the natural electrical charges they carry. For instance gelatin has a positive ionic charge while polyphenols (tannins extracted from grain husks and hops) as well as yeast cells have a natural, negative charge. When introduced to the same liquid, negatively charged colloidal (protein and polyphenol) material are electrically attracted to the settling gelatin particles, much in the way that the opposite ends of magnets attract. This neutralizing effect ties these particles together in large enough "Floc" to settle them out of suspension. This is fine until another culprit, haze causing proteins, come into play. Proteins have a natural positive charge, obviously our gelatin won't drop these out. Luckily, negatively charged Bentonite can be used in conjunction with the gelatin, doing the same thing but with material of the opposite charge for total clarification.

The second major aspect of clarification is adsorption, (not to be confused with absorption) where, while no electrical charge is at work, reactions take place at the molecular level to create surface tension, be it solids, liquids, or gasses causing them to attract to one another. Ideally a clarifier (which, in this discussion, removes haze causing proteins) or fining (which drops solid particulate, such as yeast, out of solution) will employ at least two of these characteristics simultaneously.

OK, enough of the theory, lets get to the clarifiers/finings and how the work:

Without a doubt, Irish moss is the clarifier most commonly used by home and professional brewers. Domestically, the dried red-brown marine algae (Chondrus Chrispus) is harvested by hand in the North-Eastern U.S. by "mossers" using special manganese-bronze rakes attached to long aluminum or wooden handles. The green moss is raked from submerged rocks two hours before and after low tide. After repeated waterings and exposure to sunlight, Irish moss is dehydrated to bring it to a uniform moisture content. Proper dehydration is important as it weakens the "skin", increases surface area and allows for easier handling of the product. For years Irish moss was sun dried, today it is dried in a dehydrator for better quality control then machined into flakes and packaged.

Irish moss is used in the food and other industries as well as in brewing for its carrageenan content. Carrageenan chemical name is D-Galactose-4-Sulfate, 3,6 Anhydro-D-Galactose. It is used in the food industry as a thickener in such common products as chocolate milk, toothpaste and ice cream. Carrageenan is useful to brewers because it is a negatively charged polymer that attracts to positively charged protein-tannin complexes (extracted from grain husks and hops) during the boil. This action is aided by the clumping of proteins in the boiling process. Irish moss settles to the bottom of the brew kettle with spent hops and hot break material at the end of the boil.

Professional quantities (6-10 g/hl or 1/3 oz./Bbl.) equals about 4 tenths of a teaspoons per five gallons, which coincides with the quantity used by home brewers which is, on the average of ½ teaspoon per 5 gallons of wort. Maximum effectiveness of Irish moss is achieved by adding it during the last 20 minutes of the boil, over boiling Irish moss can degrade it and make it ineffective. Optional: Experiment for best results by Increasing the amount of Irish moss used in high protein worts (i.e. high 6-row or wheat content) or rehydrate the flakes in ¼ cup of warm water for 30 minutes before use to soften the skin.

Used mostly by professional breweries, treated Irish moss works very much in the same way as regular Irish Moss, except that it is mixed with sodium bicarbonate and ground to a fine powder for better solubility. Know advantages are, better settling of both hot and cold break material leading to cleaner fermentations and, in test batches, improved settling of yeast in the fermenter.

For 5 gallons of beer, mix 1 gm (¼ tsp) in 4 oz cold water. Stir or shake well and add 20 minutes before the end of boil.

Laying for millions of years in unique beds of mineral-rich, prehistoric volcanic ash, Bentonite is mined in Wyoming from naturally perfect veins of this clay-like substance. Bentonite is used as a fining agent to clarify and chill proof beer by removing colloidal material from solution. Due to the large amount of deposit left behind, it should be used toward the end of secondary fermentation or lagering, then racked one or more times before bottling or kegging. Bentonite selectively removes undesirable compounds such as phenols, haze causing proteins, and tannins (The negatively charged plates in this clay-like compound draw out the positively charged proteins and color altering tannin complexes through adsorption and coagulation). Bentonite is actually used more in the wine and juice industries, and often in conjunction with gelatin (to remove excess tannins) or kieselsol (a silica fining agent covered later) than in brewing these days but it is still a very effective clarifier for home brewers, particularly in its ability to remove select, haze causing proteins. In case you're wondering, the reason Bentonite is no longer used by most breweries is due to the large, inconvenient amount of sediment it leaves.

Industry identifies maximum effectiveness of Bentonite by testing a 5% (5g/100ml) solution, adding it at to the brewers wort or vintners must, then incubated at 100° F for 24 hours to check for wort turbidity. A chart is then used to determine the most effective concentration of Bentonite to use (somewhere between .1 and .5 parts-per-thousand). To save you the drudgery, I have found the following to be best for myself and, hopefully most home brewers: Bring 1 cup of water to a boil and add to a blender or small food processor. Turn to high speed (you always knew that Frappé setting was good for something) and sprinkle in 1 teaspoon Bentonite, after 2 to 3 minutes turn off, let stand for 60 minutes, then mix for 5 minutes to form a smooth consistency. Use two tablespoons of this slurry per 5 gallons, thoroughly clouding the beer (without splashing or oxidizing of course). It's important to note that simply pouring Bentonite in can cause it to clump and fall directly to the bottom. Seal the remaining slurry, refrigerated in a small sterile jar, as this mixture will be enough to clear about 8 batches of beer. Bentonite will work quickly, within 24 hours in most cases but needs 2 or 3 days to compact before racking.

Quick, what miracle product tenderizes meat, aids in digestion and a chemically reduces haze causing proteins in beer? Papian enzyme of course, a proteoletic or protein degrading enzyme that is used during the secondary fermentation or lagering stage.

Through the miracle of hydrolysis, papian has the ability to break down high molecular weight proteins into simpler, soluble proteins that do not affect beer clarity, yet are essential to foam stability and other desirable flavor characteristics. Excessive amounts however can lead to the breakdown of medium weight proteins and can effect head retention if allowed to pass into the bottle or keg unpasteurized. The use of papian is falling out of favor in the brewing industry as more effective clarifiers take its place. To use, stir Papian in at bottling or kegging. The enzyme will have done its work within the two to four weeks your beer needs to naturally condition.

I'll freely admit that I have never used Papian enzyme So I would encourage you to follow the dosage recommended on the label of the Papian enzyme you purchase, as different forms vary in the dosage required.

Eggs in beer? No this isn't a breakfast beer or the next craze of the mega brewers, egg whites have been used in the past as a kettle coagulant to settle hot break trub. I know from experience that cooks have been using egg whites to clear beef stock for years, in particular for the finest of broths, consume, in which clarity comes second only to flavor. The magic ingredient in egg whites (please note that yolks are not used) is albumin, a water soluble protein which coagulates when heated. I have to admit that I have not been able to find and hard facts on the exact use of egg whites in brewing so I would have to guess that the method of clarification must be adsorption.

As I remember clarifying beef stock, the egg whites (3 to 4 per gallon) would be thoroughly mixed in cold broth. Heat is slowly applied and as a gentle simmer begins, the egg whites will eventually form a membrane on the surface and sick to the edges of the stock pot. About 1 hour or so after a gentle boil broke though the surface, the clear broth would either be carefully ladled off or removed from a spigot at the bottom.

No clarifier I have researched has the long history of use as does isinglass, in fact its story is a good history lesson on the evolution of mans use of finings: Long before the techniques of producing good earthenware were discovered, fermented beverages were stored and transported in various types of animal skins and, probably, the air sacks of large fish. It is hypothesized that these acidic beverages, many spoiled microbially, would hydrolyze the free collagen from the walls of these containers and, in doing so, automatically clarify themselves (mm, mm, good!). Isinglass as an alcoholic clarifier, in fact, was known in biblical times and also understood by the Mayans in the Western hemisphere.

Contemporary isinglass is mechanically reduced to a powder or a coarser material known as shred from the dried swim bladders of fleshy fish such as catfish, sturgeon, thread fins etc. The swim bladders are removed at capture, washed and sun dried. In this form they are known and traded on the world market as isinglass leaf. Isinglass contains collagen in an insoluble form, yet it is loosely enough bound to be easily dissolved in properly acidified water, thus binding very tightly to insoluble material in unfiltered beer (i.e. cold break material, hop or grain tannins and yeast cells). Collagen has a positive electrical charge and its inherently long, complex molecular structure gives it a strong attraction to yeast cells as well as the ability to reduce haze causing proteins. Isinglass settles much of the natural particulate in beer in a dense, compact layer in the bottom of the storage vessel, resulting in a bright beer with little waste. Another side benefit of Isinglass finings is that some polyphenol and lipid material is also removed, improving beer foam, flavor and stability. Isinglass is commonly available in three forms; flocked, powered or as a shred.

Proper use of Isinglass involves making a properly acidified solution. To do this use citric, malic or, tartaric acid to acidify water to a pH of 2.4 - 3.0. Because the collagen produces a thick, viscous liquid, a solution of 0.5% by weight (finings to water) should be made. For 5 gallons of home made beer this would equal .04 oz. (½ teaspoon) Isinglass per cup of water (.07g/230ml). Slowly mix the finings into the total amount of sterile, acidified water needed at 60° F by stirring vigorously with a sanitized spoon or small whisk (60° F or less is an important point here, as warmer temperatures will degrade the isinglass mixture, rendering it ineffective). Mix occasionally for half and hour, then cover and let this solution stand at approximately 60° F overnight, as optimum solubility of the collagen will take about 24 hours. Stir once again the following day, the mixture should have turned into a thick, opalescent, viscous solution. Mix this solution into one pint of the beer to be treated, then thoroughly stir in at kegging or bottling. Isinglass should drop the beer bight within 2 to 5 days. Serve undisturbed, or rack to a bright tank for carbonation or serving.

Instant, or prehydrolysed Isinglass is also available, most notably a product called Drifine, which can be used at the same ratio as regular Isinglass. Simply blend at high speed for 2 to 3 minutes, then let to stand for 20 minutes at 60° F before use. A final note: While 8 oz. of water gives the same dilution as that recommended for professional use, 4 oz. of water seems to work well in my test batches, especially when fining lighter beers that could be affected by the high acidity of the water used in preparation of Isinglass.

One of the original home brewers clarifiers, gelatin is a positively charged protein, derived form pork or beef skins and bones. While not overwhelming when used alone, gelatin reduces polyphenolic compounds (astringent or bitter husk and hop tannins) by attracting these negatively charged compounds, along with yeast cells, drawing them to the bottom of the bottle or fermenter. To remove positively charged haze causing proteins, commercial brewers and vintners often use gelatin in conjunction with negatively charged silicon dioxide. Together they form a dense coagulum, resulting in rapid clarification.

Optimum use of gelatin is a 1.5% solution (1.5g in 98.5g water, or 1 tsp. gelatin in 6 oz. water). Add gelatin to room temperature water and stir thoroughly so as to allow all gelatin granules to "bloom" for a few minutes. Heat gently while stirring to ensure that the gelatin is completely dissolved until the water temperature reaches 140° F. Let cool to room temperature and add at racking or bottling, allowing 3 to 6 days for proper clarification. Note: as previously mentioned, it is not uncommon in industry for some clarifiers to be used in conjunction with others, for instance, Bentonite can be used prior to gelatin fining to remove excess, haze causing proteins.

Had Mary Poppins been a fining specialist, perhaps she would have sung a happy song called polyvinylpolypyrrolidone. PVPP, better know as Polyclar, a white, powdered substance is a very useful fining for the home brewer. Originally derived from Nylon 66, PVPP (not to be mistaken with PVP, which is a slightly different product) is manufactured through a process in which N-vinyl-2-pyrrolidone is polymerized, leading to the cross linking of homopolymer chains (got that?). Two types of Polyclar are used in the brewing industry; Polyclar SB100 (formerly known as Polyclar AT) for general use and rapid settling, and Polyclar 10, a finer powder than SB100, which has more surface area per dose and greater adsorptivity, but slower settling times. I should note that Polyclar is not only used as a clarifier but is also considered a "stabilizer" in industry.

Polyclar offers such advantages as high efficiency, reduction of wort darkening and off flavors from oxidation (higher quantities will actually reduce hop bitterness and lighten the color of beer), removal of excessive, harsh tasting phenols, and best of all, it's easy to use. A real advantage to Polyclar is that not only does it reduce oxidation in beer, PVPP selectively removes haze causing polyphenols and not proteins important to foam stability and mouth feel. On the other hand, excessive use of Polyclar can accelerate beer deterioration through exaggerated removal of polyphenols as well as cause poor carbonation of bottled beer due, its ability to aggressively drop suspended yeast cells prior to conditioning. Because Polyclar is insoluble, it is recommended that the bright beer be racked off its sediment if used in secondary fermentation. No side effects are likely if Polyclar is ingested, it's non-toxic and is used in the pharmaceutical and food industries. Still, it's a good idea to carefully decant beer from a bottle, or discard the first glass or two drawn from a keg.

To use, make a 5% slurry (5g/100ml) or, for the home brewer, 2 Tablespoons per 6 oz. sterile water. Mix gently, yet thoroughly in the priming vessel and bottle. If kegging, gently stir in after racking, evenly distributing the Polyclar mixture throughout the beer for best results. For your information, the manufacturer recommends constant mixing of the Polyclar in the beer tank for 1 hour after addition, you can try gently agitating your keg or bottles to see if this helps.

Sometimes called by its German name, Kieselsol, Silica gel is a potent, if not the best single haze clarifier available. Modern manufacturing has made it possible to produce a "hydrous silica gel" with pore sizes of very tight specification. This translates into a product made to adsorb only those proteins responsible for chill haze formation, leaving foam retention and mouth feel unaltered. Silica gel is also convenient to use as it usually comes in a liquid form.

Silica gel is best used in secondary fermentation, adding ½ oz. (1 teaspoon) per 5 gallons of beer. Add slowly and uniformly with thorough mixing, allowing 2 to 4 days for the beer to clear. Rack to keg or bottle with appropriate priming solution and fresh yeast. One hesitation with the use of silica gel as a fining is that its use in unfiltered beer has not been approved by the FDA. In fact, the FDA has a mandatory warning stating that beer treated with silica gel must be decanted before drinking.

Used mostly by wineries, Sparkloid is a polysaccharide mixed in a diatomaceous earth carrier. Sparkloid has a strong positive charge making it a powerful clarifier, dropping out yeast cells and tannin complex materials.

For use in 5 gallons of beer or must, use at the rate of .15 oz. (4 gm) per 8 oz. (230 ml) of boiling water. Maintain this mixture at a simmer for 15 minutes until the tiny globules of clarifier have dissolved into a smooth mixture. Stir the hot solution into the secondary fermenter or lagering vessel and mix thoroughly, allowing 36 to 48 hours to settle.

Sparkolloid is preferred by many wineries because it doesn't strip wine of subtle flavors as some clarifiers can. Because it does not remove haze causing proteins it is often used in conjunction with Bentonite. Mead makers take note, Sparkolloid is probably the single best product I am aware of for rapid and thorough clarification of meads.

For your information there are other clarifiers that have been used in the past or present by brewers and wine makers. Some items, like egg whites and wood chips seem to be right out of the X-files. I'm listing these items to round out the article, who knows, maybe one of these clarifiers are just what you need to perfect your beer....

Boiled and steam sterilized until no flavor is imparted by the wood, wood strips rely on their large surface area to attract yeast cells and other small particulate out of suspension in the secondary fermenter.

Drops yeast and other colloidal material much in the same way Isinglass does. Used after fermentation, Clearfine is a convenient product that can be mixed and used almost immediately as needed.

Used at 20 to 30 PPM as a chill proofer. Tannins are added to encourage the formation and sedimentation of protein-tannin complexes while the beer is in cold storage. This method has mostly fallen out of favor with brewers because exact amounts are hard to determine and improper use can cause more problems than it solves.

Ah, genuinely cold filtered, bottled draft beer. Actually this is more than a marketing gimmick, beer must be very cold, approximately 34° F, at its maximum liquid density, when filtered because soluble haze precursors can pass through a filter only to become soluble again (i.e. chill haze) if the beer is refrigerated to a temperature lower than when it was originally filtered. Keep in mind that many of the clarifiers discussed in this article are used in professional breweries and wineries to make filtration of their products easier, with less waste and lower expenses due to the decrease in time and filtration media needed. One caveat; filtration can remove not only haze causing proteins, but foam stability and mouth-feel associated proteins as well. Still, for the home brewer, filtration is certainly a viable option. Cartridge porosities of .5 micron (polish filtration) to 2 micron (coarse filtration) can render your beer crystal clear in a matter of minutes rather than days. Keep in mind that you will have to be able to artificially carbonate your beer in kegs and counter pressure fill if bottling. If, however, you are seriously bothered by anything less than crystal clear beer, I would recommend that you do consider filtration.

Many of the quantities listed for use with the finings are based on what professional breweries are using, then adjusted to the amounts that seem to work best for the average 5 gallon home brewer. Due to different dynamics of smaller brew lengths (5, 10 or 15 gallons) made by home brewers, exact scale downs do not always work and are not entirely linear. I recommend that you start with the amounts advised in this article. Due to many possible variables you may find it necessary to increase or decrease the amounts suggested to get optimum results.

Keep in mind that with most clarifiers, less is often more, as excessive quantities of certain clarifiers can actually decrease their effectiveness or strip the beer of necessary components or flavor characteristics. For instance, overdosing can cause some clarifiers to actually attach to suspended particles and do nothing more than changing their charge value, restabilizing them and leaving even more suspended material in solution, worsening your haze problems! Another interesting fact is that if too much yeast is present, fining action will be quite poor, always fine at bottling, in the secondary fermenter or, no less than 4 days after high kreusen has subsided.

Experiment with different clarifiers, in particular, the ones that deal with what you perceive to be the most annoying kind of clarity problem in your beer. You will soon know what works best for you.

·         James A. Vontagoli of Sea Moss Inc.,

·         Mr. Michael Grace of James Vickers Ltd., International Specialty Products (ISP)

·         Cellulo Co.

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