The HI96814 Digital Wine Refractometer converts the refractive index of wine juice or must to sucrose concentration in units of percent by weight, % Brix (also referred to as °Brix). The conversion used is based on the ICUMSA Methods Book (International Commission for Uniform Methods of Sugar Analysis). Since the majority of sugar in grape juice is fructose and glucose and not sucrose, the reading is sometimes referred to as “Apparent Brix”.

In addition to % Brix, HI96814 includes two other scales used in the wine industry: °Oechsle and °KMW.

°Oechsle (°Oe) is mainly used in the German, Swiss and Luxembourgish winemaking industry to measure the sugar content of must. The °Oe scale is based on specific gravity at 20°C ((S.G.(20/20)) and is the first 3 digits following the decimal point. One °Oe is roughly equal to 0.2 % Brix.

°Oe = [(S.G.(20/20)) - 1] x 1000

°Klosterneuburger Mostwaage (°KMW) is used in Austria to measure the sugar content of must. °KMW is related to °Oe by the following equation: °Oe = °KMW x [(0.022 x °KMW) + 4.54] 1 °KMW is roughly equivalent to 1% Brix or 5 °Oe. °KMW is also known as °Babo.

“Potential” or “probable” alcohol is an estimation of the alcohol content (% vol/vol) in finished wine based on the conversion between sugar and alcohol. This conversion depends on many factors, such as the type of grapes, the grape maturity, the growing region and yeast fermentation efficiency and temperature.

The HI96814 is an easy to use tool for winemakers for measuring sugar in grapes or must, in the field or in the lab.

• Designed for wine sugar analysis
• Temperature Compensation algorithms based on sucrose solution
• 0 to 50 % Brix range with a ± 0.2% Brix accuracy
• 0 to 230° Oechsle range with a ± 1 °Oe accuracy
• 0 to 42° KMW range with a ± 0.1° KMW accuracy

Refractive Index

The HI96814 takes measurements based on a sample’s refractive index. Refractive index is a measurement of how light behaves as it passes through the sample. Depending on the sample’s composition, light will refract and reflect differently. By measuring this activity with a linear image sensor, the sample’s refractive index can be assessed and used to determine its physical properties such as concentration and density. In addition to the linear image sensor, the HI96814 uses an LED light, prism and lens to make measurement possible.

Variations in temperature will affect the accuracy of refractometry readings, so the use of temperature compensation is highly recommended for reliable results. The HI96814 contains a built-in temperature sensor and is programmed with temperature compensation algorithms in accordance with the ICUMSA Methods Book Standard for a percent by weight sucrose.

Making a Standard % Brix (Sucrose) Solution

To make a Brix Solution, follow the procedure below:

• Place container (such as a glass vial or dropper bottle that has a cover) on an analytical balance.
• Tare the balance.
• Weigh out X grams of high purity sucrose (CAS #: 57-50-1) directly into a beaker.
• Add distilled or deionized water to the beaker so the total weight of the solution is 100g.
• Note: Solutions above 65% may need to be vigorously stirred or shaken and heated in a water bath to roughly 40°C (104°F). Remove solution when sucrose has dissolved and allow to cool before use.

• Easy to clean and corrosion-resistant

• Battery percent level remaining at startup and low battery indicator

• To conserve battery life the meter shuts off automatically after three minutes of non-use

• Water resistant ABS plastic casing designed to perform under laboratory and field conditions.