I don't think anyone said Polyclar doesn't work, it does and if used properly works very well.
Wall did mention that he found 5.2 less than perfect, which I think is fairly widely agreed with, not at all related to PVPP.
I think there is a lot of misunderstanding about what chill haze is and how we combat it.
Chill haze is a temporary association of Tannins (more properly Polyphenols) most of which are extracted from malt husks. If Chill or temporary haze forms and then warms up, disassociates is then cooled and reforms... you will end up with permanent haze. Basically permanent haze has the same chemistry as temporary haze but doesn't go away.
Remember that Polyphenols are a family of chemicals and there are lots of different Polyphenols, there are also lots of different Proteins, some proteins will under certain conditions combine with some tannins and form a haze particle.
Clearly the more of the tannins and proteins that engage in haze formation there in the beer the more haze forms and generally the more likely/easy it is to form and the more likely the formation of permanent haze.
You do not need any chemicals to combat haze, we use kettle finings Irish Moss, Whirlfloc Isinglass, Gelatin, BrewBright* and process aids like PVPP, Silica... (these are not fining agents) to speed up the processes that will happen naturally if you are patient enough. * BrewBright contains both a fining and a process aid.
Reducing the amount of haze forming agents in the beer will result in less haze.
- Tannins - Milling finer makes tannins more available. Higher pH will extract more tannins. Over sparging will also extract more.
- Proteins - The total amount of soluble protein is fairly well determined by the malt, all we can do by controlling the mash temperature and pH is control the size of the protein. Long protein rests will make for more smaller protein, this will degrade desirable head forming proteins and is generally not recommended in modern brewing with well modified malt. Boiling preferentially removes higher Molecular Weight (MW) protein, but all protein is to some extent reduced by boiling, so longer more vigorous boils reduce protein, my default boil is 90 minutes, longer for high gravity (will also have more protein)
In the kettle
Longer, better boils cause more protein to coagulate, adding Carrageenan (the active ingredient in Irish Moss) in the form of Irish Moss, Whirlfloc, Delta Flock BrewBright will help the coagulated protein clump and fall to the bottom.
- Not leaving it in the bottom of the kettle undoes to some extent the benefits of boiling (getting high MW protein out of solution). This sediment is called Hot Break. It can't really be filtered, sieved or trapped on a stocking, with very few exceptions even big brewers leave it in the kettle/whirlpool
- PVPP (as contained in BrewBright) chemically binds the tannins that form haze. Adding the PVPP engineered for low temperature (in fermenter) like Polyclar to the kettle wont help you, the PVPP in BrewBright is very effective at boiling temperatures.
- The dosing of all fining/process aids is critical. too much can cause light fluffy trub that is hard to separate from the wort causing increased waste of good beer (=bad). Not enough and the trub settles very slowly and in the case of BrewBright not enough of the tannins are removed to reduce or eliminate haze.
There has to be some protein in the wort for head building, mouthfeel and as a yeast nutrient, with a good boil and effective trub separation, add to this the fact that the types of barley used for brewing are specifically breed for brewing and are going to give the best possible combination of proteins and starches... for brewing. The protein that doesn't coagulate and the protein that forms cold break will provide all that the beer needs. there is some discussion about removing cold break, if I were using 6-row malt with its higher protein content then yes it would be a matter for concern, as it isn't available in Australia (nor pretty much anywhere outside the US) I don't really get too concerned about cold break.
That said if I were brewing an extremely pale light bodied (lawn mower) beer or a very delicate Kölsch I might try to eliminate/reduce the clod break.
After fermentation, if the beer is chilled and there are enough residual haze forming agents - Haze will form.
- Storing the beer long enough and cold enough and these haze particles will fall out, this is often called lagering or chill proofing. It is critical that the beer not warm up or the haze will go back into solution, racking the beer off the haze means it can be packaged in kegs or bottles, allowed to warm back up and then chilled again with little or no haze formation - as what forms haze is gone.
- Isinglass will accelerate the precipitation of haze particles and yeast, Gelatine wont act on haze, tho it may help yeast to sediment
- PVPP (as is in Polyclar) will chemically bind residual polyphenols, 70/30 (from the makers of BrewBright) is a combination of PVPP and Silica the silica attaches it self to the key MW proteins and the PVPP to tannins as previously so it is attacking both sides of the problem.
You can make perfectly clear chill proof beer without any of the finings/aids but it is a long demanding process. The finings and process aids make it easier to achieve commercial quality beer. If you are going to apply them read up on the products and use them properly.
Personally I find few beers really need zero haze, It's nice to know how, but I suspect far from necessary in home brewing. Over my life I would have drunk more Coopers than all other beers added together - so I'm not drinking with my eyes.
Mark
Further reading
View attachment 01_-_Beer_Stabilisation_part_11.pdf
View attachment 04 - Beer stabilisation part 21.pdf
View attachment 02_-_The_function_of_wort_boiling11.pdf
The learning resources at the IBD are very good basic introduction to many aspects of brewing - they are
FREE!
And we haven't evened mentioned filtering...
M
