The number of homebrewers and microbreweries has grown tremendously in Australia over the past 30 years. Interest in the variety of beer types can be seen in the choices that are available to the consumer. Often times brewers start by using a malt extract to prepare wort that is boiled before starting the fermentation process with yeast. The malt extract is prepared from natural grains such as wheat, barley, and rice. More experienced or adventurous beer makers prefer to make their own malt extract. Crushed grains that have been allowed to begin to germinate and dried in a kiln are known as malt. The malt is extracted by steeping in water at 60 to 70°C in a process known mashing. This is where the alpha and beta amylase enzymes are activated, converting the malted grains into fermentable sugars.
The pH of mash is a critical parameter to monitor; it must be maintained between pH 5.2 and 5.6 for optimum enzyme activity. As the malted grains are broken down, organic acids are formed which can lower the pH of the mash. This can result in incomplete conversion of starch to sugar, as amylase activity decreases at a pH less than 5.2. Therefore, pH should be measured and periodically adjusted, if necessary, throughout the mash process. Because of the high temperatures of mash, the pH observed will vary greatly with temperature; this is an important consideration if using a pH meter without temperature compensation. A hot mash will read at a higher pH than a mash cooled to room temperature due to the variation in ion activity. Meters with temperature compensation will display a reading unaffected by the temperature of the sample, providing users with an accurate pH measurement.
Any brewery needs a solution to monitor pH in their incoming water, mash, wort, and finished beer. For beer analysis, Hanna Instruments recommends the HI98190 waterproof pH meter with the HI1296 titanium body pH electrode. The electrode is made with high-temperature glass with a temperature range of 0 to 80°C allowing it to be used at the elevated temperatures needed for mashing without shortening the electrode life. The electrode also features a built-in temperature probe, allowing for temperature compensation without requiring an additional probe. Any brewer will appreciate the durable titanium body and shield around the pH glass bulb of the electrode. Not only does this provide a rugged measurement solution, but the titanium body also transfers heat to the temperature sensor, enabling the user to obtain rapid results. The stability indicator let the customer know when the reading was stable, ensuring that the correct reading was always recorded.
The HI1296 features a renewable cloth junction, allowing for easy clearing of debris that might clog the junction.
Instructions for calibration are displayed on the main screen, which gives the customer confidence in calibrating the instrument. The HI7061L cleaning solution is recommended for periodic cleaning of the electrode glass and continued accurate measurements.
Overall, the HI98190 is a perfect tool for pH monitoring needs.