Whirlfloc Usage

Nosybear

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A couple of days ago I was making a three gallon beer. Based on the beer lore I'd always heard that you don't have to be precise with whirlfloc measurement, I just chucked a tablet in. It fizzed as always, dispersed and I finished my boil. I was very surprised to find that my wort's pH had RISEN in the boil (not supposed to happen that way). Searching my mind and notes for reasons that it may have happened, I came back to whirlfloc. Yes, it's refined carageenan but it also contains baking soda to disperse it, hence the "fizz". A tablet weighs about 2.4 grams, so I was adding a lot of alkali back to my acidic wort, resulting in a higher pH after the boil than before.

So being the science and engineering-minded guy I am, I did the math. I weighed 10 Whirlfloc tabs to get an average of 2.4 g/tab, most sites recommend a tab for 10-15 gallons of wort, so I used 10, or 0.24g Whirlfloc/gallon (divide by 3.875 to get grams/liter). Then I checked the BSG site for Whirlfloc T: They recommend 2 tablets per barrel, 31 US gallons. Using that math, I came out with a safe figure of 0.2 g/gallon.

Why is this important? Beer pH is an important determinant of its flavor. Yes, the yeast will lower the pH but I've always read that the pH going into the fermentor should be between 5.0 and 5.3. The overdose of Whirlfloc got me to about 5.6. So in the future, I'll be crushing the Whirlfloc tab, measuring by weight what I need to add and using that amount to minimize the pH increase.

Hope this is useful to you!
 
huh that's interesting. I usually split one in half for a 5 gallon batch, but PH never even occurred to me.
 
Wow! Never thought in terms of pH when using Whirlfloc. Been using a full tablet for 5.5 gallon batches and I normally mash at, or very near, 5.4. Thanks for the tip.
 
Interesting thanks for sharing. I usually use 1/2 tab for 5 gal anyway but good to know it can affect pH
 
It was one of those sciency moments when something unexpected happens and you wonder, now how the heck did that happen. I tell my grandkids those are the most valuable moments in life.
 
I only brew 10 liter batches 4.75 gallon boil, 3.5 gallon ending kettle volume.... never use more than 1/2 a tablet... I may cut that back to 1/4 with this information in hand
 
I only brew 10 liter batches 4.75 gallon boil, 3.5 gallon ending kettle volume.... never use more than 1/2 a tablet... I may cut that back to 1/4 with this information in hand
I got tired of cutting tablets - at best an approximation as they tend to crumble. Now I'll crush them and weigh what I put in. The rest of the powder goes back into the bottle.
 
Can you buy whirfloc g? Its granulated instead of tablet. Easier to weigh out instead of breaking them.

I never thought of ph change but using too much clarifier can actually cause the trub to be harder to settle. It forms a big fluffy pile instead of a compact pile.
 
Can you buy whirfloc g? Its granulated instead of tablet. Easier to weigh out instead of breaking them.

I never thought of ph change but using too much clarifier can actually cause the trub to be harder to settle. It forms a big fluffy pile instead of a compact pile.
I was looking for it, available in 5 pound bags from BSG. I can crush the tabs.
 
I've actually never used the whirlfloc tabs myself. I have used Irish moss in the past, but honestly never noticed a ton of difference, so after I ran out I just started using gelatine.
Would Irish moss still have the same effects you desire in using the whirlfloc tabs but without the binding agent? I realize the topic at hand is the unexpected rise in ph, and perhaps cutting and chopping tablets isn't that big of a deal, but if Irish moss serves the same purpose, you could simply measure it out and skip the cutting, chopping and whatnot.
 
Irish moss is carageenan, too. Whirlfloc is refined and doesn't smell like a dock at low tide. I was looking for Whirlfloc g, the powder, but could only find it in 5-pound bags. The tabs don't seem that hard to crush so out comes the mortar and pestle.
 
I monitor pH during the boil and I adjust the pH at the beginning of the boil to 5.1-5.15. It moves around sometimes depending on which acid I adjust with. If I adjust it with lactic acid it stays at that pH for the duration of the boil. If I use phosphoric acid it comes up to 5.2 or so at the end of the boil. I have always used whirlfloc and Irish moss in almost every beer. Next time I will take a pH reading before and after whirlfloc to see if it raises the pH.

I have never noticed if whirlfloc raises pH, and if it did it wasn't a huge problem. I use a full tablet plus a teaspoon of Irish moss in 5 gallons, so if it affects pH it should show up in a before and after test.
 
I really have no other explanation as to why the pH rises during the boil. And that fizzing as the Whirlfloc dissolves is the sound of rising pH. The recommended dose is 2 tablets per barrel of wort, meaning using one in a 5-gallon batch is three times the recommended amount. And another thing: This afternoon I was reading George Fix's Analysis of Brewing Procedures, where he mentions that high pH worts tend to have coarse bitterness regardless of the hops used. Interesting, and another reason for me to use the smaller amounts of Whirlfloc. I don't think Irish Moss would be a factor - it isn't made with baking soda.
 
high pH worts tend to have coarse bitterness regardless of the hops used
Absolutely. It's funny that a lot brewers think that once they get the pH correct in the mash, they're done. The pH needs to watched all the way through to the finished beer. Higher pH in the beer makes the bitterness sharp and overall the beer has a tendency to lack a smoothness and can be "flabby". If you have a beer that has a rough finish, check the pH. I have had finished beers that were too bitter, the pH was @ 4.6, I added phosphoric acid and lowered the pH to 4.3. The bitterness was less pronounced and the was much smoother. Darker beers do benefit from a higher pH and allows for the roasted grain to come through, but lighter colored beers need a lower pH.

Reducing the dosage of whirlfloc is certainly not a bad thing to do, most people overdose whirlfloc. I have a tendency to over do the carrageenan/whirlfloc thing too, but I never noticed a significant rise in pH, it has me curious.
 
This is a great heads up on pH. I would like to toss the temperature at the time of the reading into the mix of variables. In an acidic solution pH does not vary with an increase in temperature much at all. In a neutral situation I would expect a variation of + or - 0.3 to 0.5 pH units. In a basic solution I think that one would see + or - 0.5 to 0.7 shifts due to temperature at the time of measurements. That being said, I am cutting back on my whirlfloc and will weigh out the additions.
 
I completely forgot to add whirlfloc to the last batch I made...a Pre-Pro lager. We'll see if it takes a long time to clear or whether I note any difference in attenuation or flavor as a result of the difference in PH. I've been over-dosing, as I suspect that most of us do, given that I've been throwing in a couple of tabs according to the label (1 tablet per 5-10 gallons) and assuming that if one is good, 2 is better. ;)
 
My guess - just a guess - is that Irish Moss would not have this effect since it has no binding agents. As noted above, if you clear with gelatin, you likely need neither WF or IM. Then again, a fining agent of any sort is totally optional in any beer.
 
I brewed an English brown Friday and monitored the pH before and after the whirlfloc tablet was added. I add whirlfloc along with a yeast nutrient, Irish moss and a small amount of bread yeast at the same time, roughly the last 10 minutes of the boil. The pH dropped lower than I was expecting (my water was too soft) at the mid point of the boil @ 5.08, after I added the whirlfloc mixture the pH came up slightly to 5.13.

It appears that something did raise the pH slightly, but it doesn't seem to be very significant, .05 isn't much. If you can get super precise with your boil pH, you easily compensate for the rise. I'm not entirely sure the slight rise was because of the whirlfloc or not, I do see this more often than not in the boil where the pH comes up slightly at the end of the boil. Maybe it's the whirlfloc, I just can't say for sure. Most times I'm landing slightly below 5.2, so it's not a big deal. Any smaller than 5 gallons, I would consider lowering the whirlfloc dose.
 
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I completely forgot to add whirlfloc to the last batch I made...a Pre-Pro lager. We'll see if it takes a long time to clear or whether I note any difference in attenuation or flavor as a result of the difference in PH.
That beer is definitely taking longer to clear. I've had it at cold-crashing temp for over a week and it's not as clear as it usually gets in that period of time. I used WLP810 on this batch which flocs at least as well as the S-23 I usually use so I expected it to d pretty well.
The beer did attenuate very well for the strain - 82%. It was a big over-pitch and I over-oxygenated it so it wasn't the perfect fermentation, lagging forever and taking a long time to finish out (lesson learned) and the resulting flavor is more confused than I would anticipate.
 
I've done that a couple of times and in my results the beer never fully cleared without the whirlfloc even using gelatin but it did have more flavor
 

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