The Role of pH in Brewing

The pH level in your mash, wort, and beer directly affects the activity of all enzymes, hops, and yeast. If you can understand the pH and control its level, you can taste more delicious beers than ever before. The more important pH is, the harder it is to understand. So what is pH, what makes it so important, and what should we know about pH, and how much should we know?

What is pH?

The term pH refers to the degree of acidity and alkalinity of a liquid. The letter “p” is the negative algorithm of the letter “H”, that is, hydrogen density. The pH scale is from 1 to 14. 7 are neutral, below 7 is acidic, above 7 is basic (alkaline). The scale progresses logarithmically according to 10 and its multiples, for example, pH 5 is 10 times more acidic than pH 6 and 100 times more acidic than pH 7.

What does pH mean for the brewer?

The pH level of the wort affects the enzyme activity. Various enzymes are activated in the wort at a certain pH level and this pH level has a sufficient range like 5.2 to 5.5. Yeast also develops well at a pH level of 5.5. As the yeast fermentation, the pH level of the must decreases, to levels that bacteria are not comfortable with. Achieving the desired pH level in the mash also affects the dissolution of the hops at boiling; It helps to regulate the protein level; It adds clarity to the beer, affects the color, and finally changes the aroma.

How pH Affects in Brewing

A little bit of chemistry and biology is enough to bring the pH level in the mash and wort to the optimum. A biological system strives to stay stable and in balance, we can call this homeostasis, the tendency of the cell to maintain its own metabolism and its internal balance in the face of extracellular events. Maintaining the pH level and resisting sudden pH changes is our topic here. When it comes to pH, a biological system tries to do this by means of “stabilizers” or buffers. Thanks to the stabilizers in the human body, for example, we can drink beer with a pH level of 3.5-4 and our blood can remain at a pH level of 7.4.

Pure water is neutral and its pH level is 7. The reason it is pure is that it always has the same number of H + and OH- ions. Some water molecules in pure water ionize as H + and OH-. If a compound with a high H + ion level is added to water, the H + level of the water rises and the water turns into an acidic structure, and the pH decreases. Stabilizers try to keep the pH level constant, if the balance of acid and base is disturbed, they try to achieve this by decreasing and increasing the H + and HO- ions.

Malted barley contains phosphate, which tells us it is an acidic stabilizer. If you are mashing with grain malt, you are ensuring that the water reaches a pH level of about 5.6 thanks to these phosphate stabilizers. After all, the internal pH level of the water you use does not matter much, because the ions in the water and the stabilizing compounds in the malt are always in interaction and change the pH of the water. Remember, the optimum pH value of the wort is between 5.2 and 5.5, which makes the mash a little more guaranteed, the hops dissolve better and the other characteristics are more easily achieved. At this stage, the mashing water comes into play.

pH and Mash Water

In order to adjust the pH level in the wort, you have to know the mineral content of the water you use. If the mineral values ​​of the water you use are published, you are lucky. Municipalities and demijohns have to publish these values ​​as well. If you use water from an open source such as spring water, well water, artesian well, pump, this job becomes impossible.

The ions affecting the pH of the wort are calcium, magnesium, carbonate, and bicarbonate ions. These ions, if emitted, are given in either ppm (one per million) or mg / l (milligrams per liter), both of which are equally measured. Calcium is the most basic ion for us. It is important to reduce the pH of the wort to 5.2 -5.5 and to overcome the stabilizing capacity of malt phosphate.

The ideal concentration of calcium is between 50 and 150 ppm. Magnesium acts like calcium but is not very useful for lowering pH. Ideal calcium concentration should be balanced with a low carbonate-bicarbonate level. Carbonate and bicarbonate ions have an adverse effect on calcium. Bicarbonates have a strong base effect and, if they reach high amounts, they raise the pH level excessively.

Carbonate and bicarbonate ions are shown together in water analysis and their symbols are CO3. But they should not be given under the heading of base and hardness and should be represented as CaCO3. This basic and hardness feature means that it consists of calcium, carbonate, and bicarbonate ions. You should compare the two values ​​for base and hardness.

If the base level is higher than the hardness level, you must remove the carbonate ions from the water so that you can prevent the pH increase in the wort. If the hardness level is higher than the basicity, we can say that the ratio of calcium versus carbonate is suitable for mashing. If both are equal and low (less than 50 ppm), it can be balanced by adding calcium sulfate or calcium chloride to make it suitable for mashing.

Manipulating pH in the Brewery

The ion concentration in the water is very effective on the pH of the mash. The type of malt is another important factor. Dark malts are naturally acidic and can cope with the stabilizing power of carbonated water and bring the pH level to the right values.

Changing the pH level of the mash in the wort is possible either by increasing or decreasing the mineral ions or by adding organic acid. Adding salt minerals is the most common method. Mineral salts such as gypsum contain positively and negatively charged ions. Gypsum combines calcium ion with sulfate ion and is the ideal source of calcium to acidify the mash. Adding a teaspoon of gypsum to 20 liters of water easily raises the calcium level to about 60 ppm.

If you boil the water for more than half an hour to purify it, you will lose the calcium in it. Because calcium and carbons combine and remain to form a white layer. You get rid of carbons but you get rid of calcium.

If you are going to use pale malt and soft water in your beer, it would be better to make an acid brew. During acid brewing, the phytase enzyme (phytase) breaks the phytin, and phosphate-containing calcium and magnesium turn into phytic acid. In other words, phytase reduces the mash pH. This enzyme works best at 30-53 degrees.

The acid brew brings the mash to a suitable level and provides mineral and nutritional support to the yeast. But if dark malt is used in beer, there is no need for acid infusion.

Another alternative to raising acid is to add lactic acid to the mash. Lactic acid cooperates well with beer and does not change the aroma of the beer. But it is necessary to pay attention to the usage rate and the amount.

Again, dark (roasted) malts lower the pH level of the mash. Even crystal malt has an acidic effect. The way to make a bad water a man is to increase the use of dark malt. It doesn’t matter much to us, but many of the world’s famous beer centers, particularly London, Dublin, and Munich, use water that is low in calcium but high in carbonates.

This is why it is not possible for them to make pale ale or lager without taking the mash to a more acidic level. That’s why they traditionally produce dark beers like a porter. Because the acidic nature of the dark malt they use creates a buffer for the carbonate in the water and balances the pH level successfully.

pH and sparge water

The sprinkler water should be below 6 as the pH level. If the high-temperature sprinkler water has a pH level above this level, the result will be undesirable compounds from tannin, silicate, and malt. These will cause a bad aroma and turbidity. The pH level may not be much of a problem as the sprinkler water will mix into the wort. It depends a bit on how much sprinkler water you use. The point to note is that the water does not contain too much carbonate.

Unless you use very soft water and very light pale malt, nothing to worry about will occur. Often times, mash takes care of itself. Things change if you’re going to make a specialty beer, so you may need to measure pH levels often.


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