Refractometers

Refractometers are inexpensive pieces of optical devices that measure the refractive index of a liquid in a non-invasive manner. Refractive index refers to the measurement of the speed of light in a medium. When light travels in a certain material, its velocity changes which results to a change in its direction. Refractive index is then measured by dividing the velocity of light in a vacuum to the velocity of light in a given medium. The extent of refraction is directly related to the refractive index.

Each refractometer is designed based on ergonomic standards; its compact and lightweight quality ensures ease of usage and calibration. Most are calibrated with Automatic Temperature Compensation (ATC) and reticle chart for clear and accurate results. Almost all refractometers are handheld and do not require the use of a battery.

There are several types of refractometers depending on their use. The most common is an alcohol refractometer, which is used to calculate the predicted alcohol content of a beverage. It calculates the sugar level, called the Brix degree, which is crucial in determining the desired alcohol content. A high sugar level will result in an increase of percentage Brix. Results can then be converted into the Brix scale.

In a practical sense, alcohol refractometer monitors the best time to manufacture or brew a wine. All that is needed is a few drops of sample to make a reading and a few minutes to carry out the test. The tool gives an accuracy of about ±0.5% alcohol as long as right standards and conditions are met. It can be tested for both raw and brewed samples as long as they are distilled.

Another common type is a salinity refractometer, one that measures salt content. It is used to test and regulate the concentration of salt water and brine. It has a scale for specific and concentration of salt in water, making it a valuable tool for research and clinical laboratories. Salinity refractometers are used in oceanography and seawater studies to determine soil quality. They also provide reliable refractive index and salinity readings of total dissolved solids of aqueous solutions.