Is it possible to use the data of protein and ash from the original sample before application to the Total Dietary Fiber Assay Procedure (K-TDFR)?

It is recommended to perform the method as per the kit booklet. 

Unfortunately it is not possible to use ash and protein values determined on your original sample for use in Dietary Fibre (DF) calculations. 

First of all protease is used in DF assay. This will partially break down the protein present in a sample. The remaining protein in residual mass will be measured using protein methods such as Kjeldahl method and subtracted from DF. 

Ash determination on the residual mass will also contain the contribution from the reagents used in DF assay, and therefore will not be accurate.