When we talk about sugar production, quality control always plays an important role to maintain sugar crystal quality. To be able to control the quality, we must know which parameters are important in the process. The most important parameter is sucrose (sugar) concentration in the solution. Sugar content shall be monitored through the process. From fresh cane coming to the factory, until wet crystal produced in the crystallizer. All the waste and by-product shall also be monitored for its sugar content to avoid any loss.
With increasing concern of parameter measurement, nowadays, a lot of measurement method that can be used. Near Infra-Red Spectrophotometer is one of the latest methods to estimate sugar content in the liquid. It is a sophisticated method to measure since it is fast and have good repeatability. However, it has a limitation that a huge database is required to get an accurate result. If there is a significant change in liquid content (such as ash content), the database shall be updated to create a new baseline.
Historically, sugar factories use simple parameters to measure sugar content. The parameters are “Brix” and “Pol”. Brix is described as a measurement of dissolved solids in sugar juice/solution. It is traditionally measured using spindle Brix hydrometer and Brix refractometer. Spindle Brix hydrometer working principle is based on solution specific gravity. The spindle immerses in the solution and the value can be read directly. An ordinary hydrometer can be used to get specific gravity value, then compared the result to ICUMSA table. Brix refractometer working principle is based on the refractive ability of the solution. The result can be read directly. Brix refractometer currently available in manual or electronic version.
Pol or Polarization is a more specific measurement of sugar solution purity. It will show the apparent sucrose content in the solution expressed in mass percent. It is measured by optical rotation of polarized light passing through sugar solution. Pol is working perfectly in pure sugar solution. To provide a simple and fast result, Brix and Pol are used together to measure the sugar content in the solution.