Everyone who works in the food industry knows how difficult it can be to measure the refractive index (Brix scale) and color of highly absorptive liquids like red wine, soy sauce, or molasses. These two measurements are particularly important to the wine industry, where measuring ingredients accurately, reducing waste, and classification (AOC) of large volumes of liquid are of primary importance.
The CI (color/index of refraction) sensor that we have developed can measure the refractive index (Brix scale) and color of liquids (color intensity and hue) at several points along the chain of production. It comprises one optical fiber folded into a “V” shape that is sensitive to a solution’s refractive index (Brix scale), and two fibers laid end to end to measure light absorption (color) in liquids. The index of refraction sensor isn’t affected by the liquid’s absorbency and can easily function in highly colored or opaque liquids. Moreover, the possibility of simultaneously measuring the refractive index and color in the same volume of sample liquid makes it possible to correct the absorption measurements, which are generally affected by the index of refraction.
In addition to wine the CI sensor can be used for a variety of liquids including fruit juice, soft drinks, and even ethylene glycol. The refractive index and absorption ranges to be covered can be adjusted according to the liquids or application, along with instrument sensitivity.