PH

Braukaiser

In mashing we tend to target the mash pH to optimize the effectiveness of the most important mash enzymes: the amylases which convert starch into sugar. In room temperature tests the pH optima for alpha amylase has been found at 5.3 and for the beta amylase it is between 5.1 and 5.3 [Briggs, 2004] (see pH and brewing water in Starch Conversion). But when their activity is evaluated at mashing temperatures and the pH of a cooled mash sample is measured it shows their pH optima at 5.7 and 5.4-5.6 respectively. This is the result of a pH shift in the mash that takes place when the mash is heated. In addition to that, the pH optimum of the enzyme is likely to shift as well. As a result, at common starch conversion temperatures (65C/150F) the pH of the mash appears 0.35 units lower than that of a room temperature mash sample [Briggs, 2004]. This needs to be taken into account when looking at pH optima for various mash enzymes. Most commonly, however, the pH optima that are reported in the literature were determined by testing cooled mash samples.

A commonly accepted optimal range for mash pH is 5.2 - 5.7 with 5.5 being optimal for starch conversion activity but many authors report wort and beer quality benefits if the pH is lowered into the 5.2 - 5.4 range [Kunze, 2007][Narziss, 2005]. Kunze in particular lists the following benefits for a mash pH as low as 5.2. Since it is a good and fairly comprehensive list I cited it here. Some of these benefits listed will be explained in the following sections [Kunze, 2007]:

• The enzymatic activity in the mash is increased as all important enzymes get activated. (except for alpha amylase which starts to suffer at a pH below 5.6)
• More zinc, an essential yeast nutrient, goes into solution
• The extract yield (efficiency) is improved
• The protein coagulation and precipitation is improved (improved break formation)
• The redox potential is improved which results in a lower susceptibility to oxygen.
• The run-off speed is improved
• The color increase during the wort boil is reduced
• Better trub precipitation and faster pH drop lead to faster fermentation and greater attenuation of the beer.
• Lover viscosity improves filterability
• The taste of the beer is more rounded, fuller and softer. The beer is crisper, more fresh and shows more character.
• The hop bitterness is more pleasant and doesn't linger
• The foam is more stable and denser
• The color of the beer is lighter
• Mash oxidation is reduced since the main culprit, the lipoxigenase enzyme, doesn't work well at low mash pH conditions
• Haze stability is improved
• Beer digestion is stimulated. This is a positive effect of the lactic acid
• Susceptibility to microbial spoilage is reduced through
• Lower beer pH: beer spoilage organism don't grow below a pH of 4.4
• Higher attenuation

Even a pH between 5.2-5.4 is already suboptimal for mashes with large amounts of enzymatic weak malts like Munich type malts. Those mashes are better done with a mash pH above 5.4 which will be closer to the pH optimum of the alpha amylase enzyme. In addition to that, when decoction mashing is used the mash pH should not be lower than 5.4 [Kunze, 2007]. While Kunze doesn't give a reason I assume that it is because boiling of the decoctions lowers their pH which may lead to too low of a mash pH for the already enzymatically weakened decoction mash.

While the targeted mash pH is generally not determined by enzymes other than the amylase enzymes it also has an effect on other enzymes which may be considered in certain mashing schedules.

If a ferulic acid rest is held at 35-40C (95-105F) the release of ferulic acid is reduced if the pH is below 5.7 [Narziss, 2005]. Because of that it is advisable to add any acidulated malt, which may be part of the grist for pH correction, after that rest has been completed.

[1]

Electric Brewery

In brewing, 'residual alkalinity' (RA) is actually what we care about (indirectly) as adding grain and salts will already lower the alkalinity and the buffering power we're left with is called the 'residual' alkalinity. Some books and articles will insist that RA is the most important water parameter when it comes to brewing. They will tell you to target a specific RA for the colour of beer you want to produce. The usual recommendation is that a low RA is best for lighter coloured beers, and higher is better for darker beers. The calculations are complicated and often calculators or nomographs (a type of fancy 2D diagram) are provided. Worrying about RA however is backwards, as RA is not something we target. What matters are the salts (for adjusting the flavour) and the mash pH (for proper starch to sugar conversion). If we do not achieve a proper mash pH after we've added our flavour salts, we simply add some acid to lower the mash pH into the proper range (more on this in a later step). The amount of acid required is usually minimal as we know the water cannot have been highly alkaline (hard), as otherwise we would have not have been able to hit our mineral targets in the first place as some of our starting water mineral levels would have been very high. Highly alkaline water is full of minerals and usually needs to be cut with RO or distilled water first in order to hit our mineral targets before we even begin to worry about mash pH.

…..

If desired, after allowing a few minutes for the salts to dissolve and mix in the boil, take a sample and measure the wort pH using the pH meter. It should be around 5.0 to 5.5 (measured at mash temperature).

[2]

Setting the Record Straight on Mash pH - BYO

• Bamforth’s range is: 5.3 to 5.8 (mashtemp) / 5.55 to 6.05 (room temp)
• Briggs’ range is: 5.2 to 5.4 (mash temp) / 5.45 to 5.65 (room temp)
• Kunze’s range is: 5.25 to 5.35 (mash temp) / 5.5 to 5.6 (room temp)
• Lewis’ statement: 5.2 to 5.5 (mash temp) / 5.45 to 5.75 (room temp)

The Kunze temperature reference is anecdotal because his textbook does not reference temperature, and Palmer bases his temperature reference on a conversation he had with Dr. Ludwig Narziss (Weihenstephan Center of Life and Food Science’s former head of brewing science for over 40 years).

When I look at these data, I see two things. The first is that there seems to be a “lost in translation” effect in play, where one camp is arguing a moot point against the opposing camp because of the difference in reference temperature. The second thing is that these ranges are all pretty similar.

Palmer discusses mash pH and beer flavor in his presentation, and distinguishes between optimal pH ranges for extract yield/enzymatic activity and optimal pH ranges for beer flavor. As it turns out the two brewing objectives are not always satisfied by the same mash pH. Go figure! That is another discussion for another day.

[3]

PH Raise from hops

Calculate how many pounds per barrel your dry hop load is, t90 pellets usually sit around a .1-.15ph increase per lb/bl. Take a ph reading before hand, say you’re at 4.2 and you’re dry hopping with 2lbs:bbl, you can usually expect to finish around 4.4-4.5. We use lactic acid to adjust PH cold side, and it’s usually around 100ml of lactic to counteract .1ph increase from dry hopping, but I’m sure that would vary depending on suppliers

pH in Mash Tun and Kettle

pH: Also, here's information from a slide of a PowerPoint on Pilsner production (The Brewing of Pilsner Beers by Alan Taylor Braumeister, VLB Widmer Brothers Brewing Co.) that I found useful:

· Target in Mash Tun: 5.4 to 5.6

This is a compromise between the optimal pH ranges for glucanase (5.0) protease (4.5 to 4.7) and amylase (5.1 to 5.8) enzymes.

Reduces: Wort and beer viscosity,

Increases: Wort color increase, Conversion time, Lautering time, Foam stability, Flavor stability.

Brewhouse efficiency, Attenuation, Perceived hop flavor quality. Fermentation and lagering time.

· Target in Kettle: 5.1 to 5.2

Reduces: Alpha acid isomerization, resulting in a "smoother bitterness. Wort color increase during boiling Possibility of microbiological infection

Increases: Polyphenol-protein trub formation, which leads to better hot and cold breaks

Hope it helps!

Just to be clear. You are talking pH at 68F?

Correct

Enzymes

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Very lightly kilned malts contain the enzyme phytase which is able to release phosphate from phytin present in the malt [deLange, 2004]. That release of phosphate serves to lower the mash pH during the so called acid rest. It not only lowers the mash pH, it also increases the buffer capacity of the mash. This increased buffer capacity may make it later more difficult for the yeast to lower the beer pH [Kolbach, 1953]. The enzyme has a pH optimum of about 5.0 which is the reason for increased buffer capacity of worts produced from lightly kilned malts (e.g. Pilsner malt) with lower pH mashes.

The β-glucanase, which is most active between 40 and 50 C (104 – 122 F) and degrades beta β-glucanes, likes it a little more acidic. It’s pH optimum is between 4.7 and 5.0.

High mash pH also favors the release of colored malt compounds into the mash [Lewis&Bamforth, 2006]. This is yet another reason why it is beneficial to mash lighter beers at the lower end of the optimal mash pH range

conclusion

A number of enzymes are active in the mash and many of them have different pH optima which makes it sometimes confusing to choose the proper mash pH. To reduce that confusion, here are some simple guidelines that can be followed when determining which mash pH should be targeted or deciding if the current mash pH needs adjustment:

• Mash pH numbers are given for room temperature (20-25 C/ 70-80 F) mash samples
• Any mash pH between 5.3 and 5.8 should be sufficient for most mashes
• A mash pH between 5.2 and 5.5 is well suited for infusion mashes with enzymatic strong malts
• A mash pH above 5.4 should be used for decoction mashes and/or enzymatic weak mashes (i.e. large amounts of Munich malt or adjuncts)

Clarity and pH

Protein coagulation

The iso-electric point of wort proteins is around 4.9 [BrewingTechniques, 1993]. But a common boil pH of 5.2 – 5.4 (room temperature sample) does not reach a pH that low and therefore the protein coagulation is not as good as it could be [Narziss, 2005]. While it is possible to lower the boil pH through the addition of acids, it is generally not done because the level of protein coagulation that is achieved at a pH of 5.2 is sufficient and reduction of the boil pH further reduces the hop alpha acid utilization.

Clarity and Calcium

Is your water high in calcium? Also remember CaCl increases.... calcium. Calcium causes clarification

Optimal pH

Best Mash pH

5.3-5.5 for pake beers

5.4-5.6 is good for less body. best for beta

5.6-5.8 for more body. best for alpha

stay below 5.6-5.8 during sparge to avoid tannins

5.2-5.4 is best in the boil. Proteins coagulate and there’s more haze stability

Knockout pH - Reddit

What’s every body’s idea KO Ph? I usually shoot for 5.2 on lagers and 5 ish on clear hop forward styles, and 4.6-4.7 on hazies (I have found a much more stable haze at this ph with a little more punch to hop flavor, and no I have no science to show why, just my experience). As crispy boi season arrives, I have been especially wondering if any one starts ferment lower for a crispier crispy boi.

• our numbers are super close to yours, we go a little lower on our light lager, around 5.0 or 4.9 sometimes. i think the science behind knocking out sub 5.0ph on hazy/hoppy beer (we do this for our house IPA that is clear) is lowering the PH at knockout helps that initial PH drop that comes with fermentation. for instance if we knock out a beer at 4.7ph, after we pitch yeast I see our first drop of PH when fermentation begins go down as low as 4.2ph. once we start dry hopping that beer we see the final PH hover closer to 4.5 or 4.6, leaving a nice citrusy hop characteristic- it’s when we get final PHs in the 4.7, 4.8+ range after a healthy dry hop that the beer begins to taste vegetal and herbal.
• 5.0 on hazies, 5.1-5.2 on wc IPA's, 5.2-5.3 on lagers/Pilsners.