Why Does the pH Level of the Mash Matter?

Brewing an all grain batch is different from brewing with malt extracts. For the artists of the brewing world looking to create unique flavours and textures, all grain is the way to go.

So how does this apply to pH in Mash? Just hold on a second, and read on!

The pH level of your all grain mash is going to greatly affect the flavour and clarity of your beer, as well as the release of enzymes and the yeasts ability to ferment. Anyone who takes the time and effort to craft their own brew will share it with friends and family. So getting the flavour, fermentation and texture just right really matters.

The level of pH in anything is dependent upon the amount of ions it holds. The concentration of minerals determine the ion count. The health of our air, water, food and soil can be measured by the amount of ions they contain. Measuring between 0-14, the optimal reading is 7. Most water and much of our food will measure at slightly higher than seven due to mineral content. Fresh vegetables will always be above 7, and meats, nuts and eggs will read below. The greater the mineral content the more alkaline the food or water will be. Healthy water should always read above 7. Anything reading below 7 will be in the acidic range and the lower it goes on the scale the more acidic it will be.

Looking now at beer and the ion concentration or pH level, there will be a difference in the desired reading required with water or food. The optimal reading for mash is 5.4. This is more on the acidic side of the scale but for taste and clarity this is necessary. So now that we have determined the right reading for the mash, the next step is getting to that desired level. The most important factor in the pH of the wort will be the level of ions in the water. Measuring the water's pH first before adding any grain is necessary. The grains will change the levels depending on which ones you use. Dark malts have a more acidic value and light grains more alkaline. If you want to brew a dark beer there will be little need to adjust the pH levels since the grain itself will create more acidity. If you are brewing a light beer there will be a need for some adjustment to get to the 5.4 range.

Chemicals are available to change the pH level of the brew and there are several to choose from. In Germany they have very strict rules for additives to beer. Only natural additives are allowed, so they use something called Acid Malt. It is made from lactic acid which is a byproduct of milk. In Canada it is packaged and sold by its actual name, Lactic Acid, and is the same product. This will assist in lowering the pH of the mash to the desired 5.4. If you really don't care whether it is natural or not, the additives used by professional breweries are available on the market. Calcium Chloride and Gypsum are two common ones, found in most home brew stores.

The amount of any chemical needed in the wort will be determined by the pH reading you get from each batch. It may be a matter of trial and error as you add more, then measure the changes. There are several ways available to measure pH levels accurately. The least expensive method is with pH strips. A pH tester kit will include test strips and a chart called the Universal Indicator paper scale. The results are obtained by dipping a strip into the wort and watching the strip change colour. The colour the strip changes to will indicate the pH level of the wort and is measured by comparing it on the chart. An alternative method is the pH meter that runs on a long life battery. It is more expensive but will give exact readings with no guess work. Results are obtained by dipping the electrode into the wort briefly. It has an electronic display screen that gives the reading.

I hope this brief article on balancing the pH of your wort has benefited you. Happy brewing!

I would like to thank this week's guest blogger B Mac (who wished to remain anonymous) for this info on the pH level in your mash. We are always taking submissions and suggestions for future blog posts. Fire off an email or leave us a comment, and I will get back to you.

Happy Brewing - Barley