title: CuSO4-TiO2 as Kjeldahl digestion catalyst in manual determination of crude protein in animal feeds.
abstract: The official AOAC manual Kjeldahl methods for determining crude protein in animal feeds have several disadvantages. For the HgO catalyst method, there are environmental concerns and a lengthy digestion. For the CuSO4 catalyst method, the digestion period is shorter, but still 90 min. A different catalyst combination, CuSO4-TiO2, makes 40 min digestion feasible. Comparison of these catalysts on a group of representative feeds resulted in a mean difference, Cu-Ti minus HgO, of 0.034% protein. Standard deviation of the differences was 0.36. A Student's t-test showed no significant difference. The method will be collaboratively studied.
mesh_terms: D000821:Animal Feed / Q000032:analysis*; D002384:Catalysis; D003300:Copper / Q000032:analysis*; D019327:Copper Sulfate; D004044:Dietary Proteins / Q000032:analysis*; D014025:Titanium / Q000032:analysis*
chemical_list: D004044:Dietary Proteins; C009495:titanium dioxide; D003300:Copper; D014025:Titanium; D019327:Copper Sulfate