Moisture amount determination (Toluene Method)

Determination of Moisture Content (Toluene Method)
Determination of Moisture Content (Toluene Method)

When the moisture content is determined by the toluene method, an organic solvent which is substantially immiscible with water is used. Water is distilled off and collected in a graduated fraction. The amount of water collected is measured to reveal the amount of moisture.

The toluene method is used to determine the moisture content in dried foodstuffs containing more than one percent moisture. Rather, it is a very useful method for the determination of moisture in milk powder and granular products and it is a widely used method to determine the moisture content of spices.

Moisture content in food products is generally carried out by oven drying. The water in the food baked under a certain temperature is evaporated and the moisture loss is calculated by determining the weight loss. After moisture has evaporated, the remainder is the dry matter weight. In the toluene process, however, toluene or xylene is used which does not mix with water and is less concentrated than water, and the foodstuff is distilled in this solution.

During the analysis, first put 40 grams of food into the distillation vessel, add 75 ml of toluene and mix thoroughly. Then it starts to heat from the bottom. Occasionally, a small amount of toluene is poured into the vessel and the moisture condensed on the walls of the vessel is reduced to the scale. Distillation is continued until the amount of water remains constant in the graduated portion. The moisture content of the food is then determined by the calculations.

Moisture (moisture) determination in foods is carried out within the scope of physical analyzes in authorized laboratories. During these tests, the standards issued by local and foreign organizations are complied with. At the same time, globally accepted test methods and test criteria are adhered to, thus achieving objective and reliable results. Moisture determination in spices (toluene method) analysis is carried out in accordance with the following standards:

  • TS 2134 Spice - Determination of moisture content