Bellevue, WA (PRWEB) March 04, 2013
Specific gravity is a measure of the density of a liquid compared to water. Water has a specific gravity of 1.000. In beer-making, specific gravity is measured throughout the process to determine the amount of total dissolved solids (sugar).
The specific gravity measured prior to fermentation is called original gravity (abbreviated OG). When it is measured after fermentation, it is called final gravity (abbreviated FG). Refractometers really shine for measuring the OG of wort. Readings are typically displayed in Brix % or sometimes in °Plato, which can easily be converted into specific gravity. Once fermentation occurs, and sugar starts to turn into alcohol, the accuracy of a refractometer becomes less reliable although many brewmasters are satisfied with FG readings obtained with a refractometer. At this late stage of brewing, some use a hydrometer alongside a refractometer to validate the refractometer’s readings.
Refractometers are preferred to hydrometers because they can provide more accurate results. There is a risk of subjectivity and likelihood of human errors in eye-balling the graduation of a hydrometer scale. Whereas a refractometer can provide digital readings, and therefore, there is no room for mis-reading. Furthermore, many refractometers are equipped with a temperature compensation feature. A brewer does not need for the wort to cool down to take a measurement. Refractometers automatically compensate measured values to the standard temperature of 20°C even when the wort is hot.
A refractometer may cost more than a hydrometer, especially if it is a digital model, but it saves money in the long run. First of all, it uses much less wort. A digital hand-held refractometer only needs 1/10 a teaspoon of liquid to take measurement as opposed to a hydrometer that requires a cup-full of it. There is so much less wort wasted, leaving a brewer with more liquid to turn into beer. Another cost-saving advantage of a refractometer comes from its durability. Unlike a hydrometer, it does not shatter on impact. Digital refractometers may seem delicate and fragile, but they are built to last because they are commonly used in harsh environment, such as on the factory floor of a manufacturing plant. Many refractometers are water-resistant and can even be washed under running water, contributing to the hygiene of the brewing process.
ATAGO has been the trusted brand for refractometers worldwide for over 70 years. The extensive product line-up caters to breweries of all sizes. The in-line process models that can take real-time readings and bench-top models that offer lab-grade accuracy are appropriate for large-scale production. The best-selling ‘Pocket’ digital models, which are small enough to fit in the palm of your hand, are just perfect for microbreweries and home brewers. ATAGO offers refractometers that measure in Brix % as well as in degrees Plato (°P).
Replacing the hydrometer with a refractometer, or at least adding a refractometer in part of the process, simply makes sense. It is the more accurate, cost-effective, and time-saving alternative.