Determine Total Dietary Fiber in Food
Dietary fiber is an indigestible nutritional component of plant-based foods, which is key to a healthy diet. For example, the German Nutrition Society (DGE) recommends that adults include at least 30 grams daily in their diet. Consumers are therefore dependent on precise nutritional information. The proven Total dietary fiber reagent kit for 100 applications (repeat determinations for 50 samples) make it easy for food manufacturers and laboratories to reliably determine the total amount of dietary fiber.
There are two types of fiber: soluble and insoluble. Soluble fiber binds with water and expands, while insoluble fiber does not. Both types form the group of total dietary fiber. Above all, polysaccharides (carbohydrates) and polymer phenolic compounds (lignin) fall under this group.
The total amount of dietary fiber is determined according to the L 00.00-18 method as prescribed by the Amtliche Sammlung von Untersuchungsverfahren (Official Collection of Determination Procedures) in accordance with § 35 LMBG.
Only the Total dietary fiber reagent kit contains three enzyme solutions tailored specifically to each other in regard to their function in the enzymatic-gravimetric method and tested by our quality laboratory. This eliminates the time-consuming search for suitable enzyme solutions. Thanks to the consistently high quality of the solutions, Total dietary fiber reagent kit can also guarantee a high degree of reproducibility. The reagent kit includes a detailed explanation on how to carry out the test and calculate the amount of dietary fiber.
Total dietary fiber is determined with the Total dietary fiber reagent kit reagent test in two repeat determinations that slightly differ from each other in terms of their mass. They are both treated with a ready-to-use α-Amylase solution to agglutinate the starch and partially break it down. Finally, protein digestion is carried out using protease and the remaining starch is broken down with amyloglucosidase.
The soluble fiber is precipitated with ethanol (95 % volume concentration), the precipitation filtered and washed with ethanol and acetone. Then the residue is dried and weighed. In the residue of the first sample set, the protein content is determined according to Kjeldahl , and the mineral content in the second. The average mass of the two residues – adjusted for the protein, mineral and blank solution content – is equal to the content of dietary fiber in the food tested.