Mastering Your Brew: How to Use a Refractometer for Effective Brewing

A refractometer is an instrument that measures the concentrations of aqueous solutions such as liquids and gases. They find use in industries where chemical compositions of samples need to be measured, such as food processing, agriculture, chemicals, and more. For instance, in the food industry, these devices help measure the concentration of sugar and salt in a sample. At the same time, in the chemicals sector, they are used for measuring concentrations of ethylene and propylene glycol, specific gravity of acids among others. There is one sector, however, wherein they can be used effectively both on industrial and domestic levels: breweries. While hydrometers are commonly used in this industry to calculate specific gravity, using a refractometer is more effective. This post explores the usefulness of a refractometer for effectively brewing beer and more.

Different Types of Gravity Measurements in Brewing

There are different units to measure the sugar concentration in a brew to help control the fermentation process and understand the quality of the brew.

Plato Gravity Scale: This is the measurement of the concentration of dissolved solids in a brewery wort. Each degree Plato is approximately equal to 1% fermentable sugars by weight in the wort.
Brix: Quite similar to Plato, Brix measures the percentage of sugar by weight in a solution. Here, the readings are mentioned in degrees (°Bx), wherein 1 Brix equals to 1 gram of sucrose in 100 grams of solution.
Specific Gravity:In brewing, specific gravity measures the wort as well as the fermented beer. It is a unitless value and a dimensionless quantity. This is relatively easy to measure and can be used by home brewers as well.

Importance of Specific Gravity in Brewing

It is important to understanding the sugar content for fermentation when brewing beer. While there are other devices to measure specific gravity, a refractometer could be a game-changer. Specific gravity is the relative density of a substance measured against some other standard substance such as water. Density of water at four degrees Celsius is widely used as a standard point for this measurement. Measurement of specific gravity is crucial when fermenting beer and wine to know the quality of the brew. Here, the specific gravity of unfermented beer or wort is calculated, and is called initial gravity. This measures the concentration of fermentable sugars. The final specific gravity is measured after the fermentation process, wherein sugar is already converted into alcohol and carbon dioxide with the help of yeast. Both these readings help determine the alcohol content and the amount of sugar converted into alcohol. Here, a refractometer measures the refractive index of wort, which can be converted into specific gravity.

Working of Refractometers and Their Application in Breweries.

Portable, digital refractometers are the best option for commercial and home brewers alike. For this, knowing how a refractometer works and its relevance in brewing beer is important. Here are some pointers.

A refractometer works on the principle of refraction, which means light rays bend when passed between two different mediums.
They may bend either towards or away from the line separating the two media. The angle formed by this bending is called the incidence angle. The angle of refraction is the one between the bending and normal ray. This angle of refraction is related to the aqueous solution sample.
Each compound or substance in the solution has a specific refractive index depending on its concentration and temperature. Hence, the bending of light and the angle changes depending on these two factors.
One can use analog or digital portable refractometers to measure the sugar concentration in beer.
You need to put only two to three drops of solution or unfermented beer on the daylight plate for accurate measurement, and it can be easily calibrated with distilled water.
Their Automatic Temperature Compensation (ATC) feature seamlessly adjusts for variations in ambient temperature. The light is passed through the prism and lens.
When using a refractometer, open the daylight plate, put 2-3 drops of beer and close it to allow the solution to cover the entire prism surface.
Now, hold the daylight plate toward a light source and look through the eyepiece. You will see a circular field with graduation; the upper portion is blue while the lower one is white.
Take the reading where the boundary line of blue and white separates the graduated scale. The scale will provide a direct reading of the concentration.

Benefits of Using a Refractometer for Effective Brewing

There are several benefits of using refractometers to measure sugar concentration in a beer sample over traditional hydrometers. Here are some pointers.

Clearly, these portable devices are handy and can be carried anywhere. Also, a small sample size is enough to get quick and accurate readings. On the other hand, hydrometers require a significantly large sample size.
It is quite easy for home brewer and enthusiasts as well to get the original and final readings for an effective brew.
The ATC feature in refractometers auto adjusts the ambient temperature. A hydrometer may require temperature correction when working with hot or cold solutions.
Refractometers use a prism and light source to illuminate the sample. They are economical as you can hold them in the direction of natural light. Some models may have a built-in light source.

While more is needed, you can reliably use a refractometer for home-based and commercial brewing. However, ensure the refractometers you source are well-calibrated and offer accurate output. In this case, you can check the collection at Triplett, which offers a variety of high-quality refractometers for brewing and other applications. Triplett is a reliable manufacturer of various multimeters and other test equipment tools. The company offers accurate, pocket-sized, refractometers that are easy to use. If you need any further information regarding these devices and their use in breweries, feel free to contact the Triplett team.