Beer pH Indicator strips measure 5 different pH values and packs contain 50 strips. The colour ranges are 4.6, 5.0, 5.4, 5.8 and 6.2.
These pH strips are very easy to use – the best time to apply them is about 5 minutes into the mash. Just dip the swab strip into the mash for 2 seconds then remove it. Shake off any excess liquid then compare against the colour chart on the packaging within 30 seconds.
When mashing, obtaining the correct pH level is important for optimum results. If the pH of the mash is wrong, your beer may develop off-flavours. However, if the pH balance is correct, your beer will achieve a better fermentation, better clarity and ultimately a better taste.
pH of the mash.
The best way to produce great beer is to ensure your mash has the correct pH. The optimum pH reading is between 5.0 and 5.4. The pH value of your mash may vary each time as it depends upon the water and the quantities and types of malt used. In most cases, the pH will be too high, so you will need to increase acid levels to achieve a pH reading of 5.0-5.4.
Increasing acidity (lowering pH)
To increase acidity you will need to add an acid to the mash. Lactic Acid is the preferred way as it mixes well with the beer flavours. It is available in either liquid or powder. Add the Lactic Acid to the mash and stir to mix, then retest the pH. Repeat until you get the desired reading. You can also use Gypsum as a substitute.
Removing acidity (increasing pH)
To raise the pH of a mash use Calcium Carbonate (Precipitated Chalk) to the rate of 1g per gallon. Stir in thoroughly to mix then retest.