Brix measurement determines pure sucrose content in samples and is not only a well-known application in the food and beverage industry, but also in the chemical segment. The degree Brix is represented by the following equation:

1 degree Brix (°Bx) = 1g of sucrose / 100g of solution
 

But does it apply to any kind of sample? Is 12 °Bx in orange juice equal to 12 g of sugar?
 

In practice, not necessarily. The Brix scale is used to measure sugar content in substances such as soft drinks, fruit juices and tomato concentrates, as well as products such as cutting oil, which are very often far away from pure sucrose/water solutions. This has led to some confusion especially when comparing results obtained with different measuring techniques (hydrometer, pycnometer, refractometer, digital density meter).

On this page you will gain essential knowledge about Brix and other related scales used in sugar content determination.

Did you know that a temperature change of 1 ⁰C can have an impact of approximately 0.1 ⁰Bx? Or even more if you measure substances with a high level of sugar?

Therefore, users must keep in mind that the Brix measured via any of the abovementioned instruments depends strongly on the temperature!

Learn more about temperature correction of the refractive index (Brix) for solutions with different concentrations of sucrose…

Developed in 1843, Balling is the oldest scale used to measure dissolved solid concentrations, principally the sugar content of wort during brewing.

Mainly derived from malt, the dissolved sugars are found alongside other substances, and the mixture is collectively referred to as "extract." To monitor the fermentation process, brewers typically collect Balling or similar measurements (see below) over time, to determine wort concentration. Because the sugars in the wort are converted into alcohol during fermentation, the sugar concentration gradually decreases over time; this gives brewers a way to estimate the final alcohol content of their beers, and also provides additional control of and insight into the brewing process, ensuring the consistent quality of their final product.

Digital refractometers eliminate operator dependency, deliver results in 2 seconds and increase results reliability.

Degrees Plato, also known as the Plato scale, is another scale that measures the content of sugar in the wort during brewing. It is expressed by percentage weight (% w/w) and by the following definition:

1 degree Plato = 1 g extract / 100 g wort

As beer has water, alcohol and dissolved "sugar", mainly derived from malt, brewers must measure this dissolved sugar in order to better control the beer fermentation process.

The temperature reference for the Plato scale is 17.5 °C; therefore, to convert a value from specific gravity to Plato the following equation can be used:

°P = 260 * ( 1 – (1 / specific gravity of the aqueous solution at 17.5°C))

Oechsle is a scale used to measure the density of grape must and is mainly used in Germany, Luxembourg and Switzerland. There are actually two definitions of Oechsle: One is referred to as "old", and is based on specific gravity; the "new" definition is based on refractive index.

"Old" Oechsle is calculated as:

Oeo = 1000(sg - 1.0)

where

Oeo (old)  = degrees Oechsle
sg = specific gravity

"New" Oechsle is calculated as:

Oen = 2639.22*nD - 3514.83

where

Oen (new) = degrees Oechsle
nD = refractive index

The Baumé scale was developed in 1768 by the French pharmacist Antoine Baumé, who built an aerometer to measure the specific gravity of liquids.

This scale allows evaluation of the concentration of any solution with the same units (Baumé degrees; °Bé) and the same apparatus (Baumé aerometer); however, it is necessary to use a specific table to determine the concentration of each type of substance. It is currently used in the industrial production of beer, wine, honey and concentrated acids. The relationship between density and degrees Baumé has been expressed in various ways during the time it has been used.  At present, at 16°C, the relationship between density and the Baumé degrees of the solution is given by the following relationships:

• Liquids less dense than water:

Specific gravity = 140 / (130 + °Bé)

• Liquids more dense than water:

Specific gravity = 145 / (145 - °Bé)

The relationship between Brix and Baumé is not linear. However, it is possible to make a very rough conversion with this simple equation:

Brix degrees = (°Bé x 1.905) - 1.6

Baumé degrees = (°Brix + 1.6) / 1.905

If you need a precise result in Baumé for your sample at your desired temperature, a benchtop digital density meter is the perfect choice.

Besides the Brix scale there are other comparable scales for indicating sucrose content in a sample, such as degrees Plato, Baumé, Oechsle and Balling. The table below presents a summary of each measurement type, along with more information about the scales.

Keep in mind that the basis for any sugar content measurement is the specific gravity of a liquid sample when using a digital density meter or pycnometer, and the refractive index when using a digital refractometer or one of the manual methods listed above.

The exact determination of Brix is very important for costs and quality control in the beverage industry. By determining an accurate Brix level, you can not only ensure the best quality required but also optimize costs, permitting your company to save thousands of dollars every year.

If a ray of light travels from one medium into another optically less dense one, it changes direction. With an increasing angle of incidence, it reaches a critical value at which no light escapes from the denser medium. If this critical angle is exceeded, total reflection occurs. The refractive index is calculated from this critical angle. As the refraction depends on the wavelength of the incident light, the refractive index is measured at the wavelength of the D line of sodium (589.3 nm) as a standard and symbolized by nD. The refractive index depends not only on the wavelength used to measure, but also on the temperature of the solution being measured.

Therefore, there is a direct relationship between the refractive index and Brix. The refractive index measured is converted directly into weight percent sucrose content (°Brix / °Bx).

Yes, the Brix measurement of a liquid fluctuates according to temperature. The Brix of a cold sample will appear higher than that of the same sample at room temperature. That is why an accurate Brix measurement needs to take temperature into account. To avoid manual calculation, which is prone to errors, the use of a  temperature-controlled digital meter is highly recommended.

One degree Brix is equal to 1 gram of sucrose in 100 grams of solution, which is equal to 1% Brix. Therefore, there is no difference between them: In this case 1 °Brix = 1% Brix (weight / weight).

A Refractometer is the simplest and most accurate tool to measure Brix.

Brix is a measure of the amount of dissolved solids in a liquid via its specific gravity, and is used especially to measure dissolved sugar. One degree Brix is 1 gram of sucrose in 100 grams of solution.

Brix in wine, as in every other substance, means the amount of sugars in a liquid. In wine Brix is measured before grapes are harvested to determine the sugar content, and therefore the alcohol content that the wine will have once the sugar is fermented. Brix should also be measured at least once per day during the fermentation process; monitoring the conversion slope allows the winemaker to adjust the temperature of the process for optimal wine quality.

While seemingly arcane, the Brix scale is useful in the culinary world, in particular with wines. Depending on the flavor and specific aims of a given wine, a value of about 18 to 24 °Bx is generally ideal.

Would you like to control the Brix concentration of your sample?

A good honey should be between 70 and 88 degrees Brix. However, honey’s quality depends on its moisture content. In short, this is because the higher the moisture content, the higher the probability that the honey will spoil during storage. According to the AOAC 969.38 standard, moisture should not be above 20%.

According to CODEX STAN 247, the Brix level for orange juice should be between 11.2 and 11.8, and consistent with the values stipulated by the national legislation of the importing country, but not lower than 11.2. However, It is recognized that in different countries, the Brix level may naturally differ from this range of values. In cases where the Brix level is consistently lower, reconstituted juice from these countries introduced into international trade will be acceptable, provided it meets the authenticity methodology listed in the General Standard for Fruit Juices and Nectars and the level is not below 10 °Brix.

Note that the acidity of the orange juice affects the Brix value. Fruit juices contain other substances, such as acids, as well. These substances also influence the refractive index and lead to lower Brix readings. Thus, Brix values must be corrected to compensate the contribution of the acids and represent the true sugar content of the sample.

Learn more about acidity and acid content determination: Download our guide.

Measure Brix concentration accurately with our Refractometers or Density Meters

One degree Brix is defined as 1 gram of sucrose in 100 grams of an aqueous solution; if the only soluble solid in the solution is sucrose, then 1 gram of sugar will raise the value by 1 °Bx.

Want to produce your own Brix standard?

Step 1: Verify the refractometer using distilled water. This should give a reading of zero; clean and calibrate the device if this value is not obtained.

Step 2: You should ensure that the refractometer surface is clean and dry.

Step 3: Place a small amount of the solution to be tested onto the prism. A couple of drops is enough.

Step 4: Look through the eyepiece while you point the prism toward a light source. Do not look at the sun.

Step 5: Focus the eyepiece, and take a reading where the base of the blue color meets the scale. This reading is the sample’s Brix.

However, measuring Brix with a classic refractometer may have some disadvantages:

• Small measuring range / requires several refractometers to cover a wide range
• No thermostating (your measurement will need to be at exactly 20 °C to be accurate enough)
• Operator dependent readings, therefore limited accuracy
• No measurement protocol.

Use a digital refractometer for an easier and more accurate measurement that will increase the productivity of your lab and save time and money.

In general, the terms degrees Brix, degrees Plato and degrees Balling are all interchangeable. All three scales express the weight percentage of sugar solutions and relate this weight to specific gravity. Specific gravity relates the weight of a given volume of liquid to the same volume of water. Liquids heavier than water like must or wort have a specific gravity greater than 1.000. Liquids lighter than water, such as alcohol, have a specific gravity less than 1.000.

The oldest scale, Balling, was established in 1843. A bit later Brix corrected some of the calculation errors in the Balling scale and introduced the Brix table. Then in the early 1900’s, Plato and his collaborators made further improvements, introducing the Plato scale. Essentially, they are the same. The tables differ in their conversion from weight percentage to specific gravity in the fifth and sixth decimal places of the specific gravity scale.

High Fructose Corn Syrup, or HFCS, is a liquid sweetener that is extracted from cornstarch containing mainly fructose and D-glucose. HFCS is used to replace sucrose in the beverage and food industries. HFCS is available in three different fructose levels, HFCS 42, 55 and 90 weight percent, and is mainly used in the USA.

As a sweetener, HFCS is often compared to granulated sugar, but manufacturing advantages of HFCS over sugar include its ease of handling and cost-effectiveness.

It is possible to measure the Brix and HFCS content either with a density meter or a refractometer. Both methods will give the same result if pure sucrose/HFCS content of a solution is measured.

Digital Density Meters and Refractometers like the Density Meter Excellence D4 and the Refractometer Excellence R4 from METTLER TOLEDO allow direct measurement of degrees Brix or HFCS %. Both measuring methods allow the automatic conversion of refractive index / density into Brix degrees or HFCS %. With both methods, the results obtained are identical when measuring pure sucrose or pure HFCS and can be compared with each other.

A Brix acid ratio is the ratio of the degrees Brix of the juice to the grams of anhydrous citric acid per 100 grams of the juice. It is one of the most commonly used indicators of juice quality as well as fruit maturity.

First, check the refractometer with deionized water; the result should be 0 % w/w or 1.3332 nD at 20 °C (consider your tolerances). Then, make sure your method is set to measure Brix at your desired temperature. Add approx. 0.3 mL of your sample to the measuring cell and press start. You will obtain a result in a few seconds.

First, check the density meter with deionized water; the result should be 0 % w/w or 0.9982 g/cm³ at 20 °C  (consider your tolerances). Then, make sure your method is set to measure Brix at your desired temperature. Add approx. 2 mL of your sample into the measuring cell using a syringe, and press start. You will obtain a result in a few seconds.