Scisol Rudolph J47 digital refractometer

The Rudolph J47 digital refractometer is suitable for food and beverage testing where samples are mostly a mixture of sugar and water. The instrument’s single flat measurement surface, temperature correction and one-button measurement capability make it suitable for heavy-use applications.

The refractometer has a fully automatic measuring system. The operator simply places the sample on the prism and presses a button; the result is displayed on a 7.5 x 10 cm backlit LCD screen. There are no shadow lines to match and no eyepiece requiring operator determination or manual adjustment.

According to the manufacturer, the refractometer corrects for errors caused by sample temperature variation using ICUMSA temperature correction tables. Temperature correction is a fast mathematical solution to obtain measurements without a temperature control system or water bath. These measurement results are most accurate when samples are composed predominantly of sugar and water.

The machine is designed for samples with a Brix range of 0 to 95° and a Refractive Index range of 1.32 to 1.53. The machine has an accuracy of ±0.3°Bx and ±0.0004 RI.

The J47 offers many of the features of other models in the Rudolph range but lacks the built-in peltier heating and cooling system for highly accurate measurements. It is a temperature-corrected but not temperature-controlled model and is a true simplified laboratory instrument.

Regardless of an instrument’s specified accuracy, a refractometer’s real-world performance depends on how well the instrument is cleaned between samples. The J47 addresses this issue by providing a flat, easy-to-clean measurement surface with no corners or crevices to trap samples and cause contamination.