2018 Sugar ERP - Method Review Book

2. Is there information demonstrating that the method meets the SMPR Method Performance Requirements using the Reference Materials stated in the SMPR? If not, then specify what is missing and how this impacts demonstration of performance of the method.

No. The method provides % recovery data and repeatability (%RSDr) data; but, the method does not provide any reproducibility data (%RSDR). Additionally, the recovery data is only provided for fructose, glucose, sucrose, maltose, and lactose. The method states that the accuracy of galactose in the method was ascertained with passing a proficiency testing program; however, no data is provided in support of this claim. Furthermore, for the recovery data, no information is provided to ascertain the analytical range being measured and therefore to ascertain which performance requirement ranges the method should fall under. While the recoveries meet the SMPR Method Performance Requirements for the three food matrices investigated (butter, corn starch, and refried beans) when assuming an analytical range of 0.1-5% reported as individual sugars for fructose, glucose, sucrose, maltose, and lactose, there is no data to indicate that the recovery for galactose meets the SMPR Method Performance Requirements. The repeatability data does report the mean value measured across the fifteen (triplicate, five days) values reported for each sample, so the analytical range is known and it can be determined whether or not the %RSDr SMPR Method Performance Requirements are met. With regards to repeatability, the majority of the matrices studied did not pass the SMPR Method Performance Requirements. It becomes difficult to fully evaluate each matrix studied because each of the six analyte sugars were measured in a variety of different matrices with no single matrix being used to evaluate all six analyte sugars. For repeatability, fructose met requirements for one out of four matrices; glucose met requirements for none of the six matrices; sucrose met requirements for nine out of eleven matrices; maltose met requirements for none of the five matrices; lactose met requirements for five of the seven matrices; and, galactose met requirements for one of the three matrices. No. As currently written, the method has a clear emphasis on fructose, glucose, sucrose, maltose, and lactose, with minimal data being provided for galactose, despite the fact that galactose is clearly included in the SMPR applicability statement. No accuracy/recovery data is provided for galactose. Furthermore, repeatability for galactose was only investigated in dairy products, two yogurts and a dried buttermilk powder, despite that fact that galactose is found in a variety of other food forms in appreciable quantities, such as honey, beets, cherries, celery, oats, etc. Additionally, the method is not able to demonstrate that it performs within the SMPR Method Performance Requirements for repeatability for glucose and maltose for any of matrices studied with those sugars. The only sugars that met the repeatability requirements for a majority of the matrices studied were lactose and sucrose; no sugar met repeatability requirements for all matrices studied. The method is not able to demonstrate that any of sugar analytes meet the SMPR Method Performance Requirements for reproducibility, as no data is provided.

3. Is there information demonstrating that the

method performs within the SMPR Method Performance REquirements table specifications for all analytes in the SMPR applicability statement? If not, please specify what is missing and whether or not the method's applicability should be modified.