Expert Review Panel for Kombucha Tea

1. Are the definitions specified in the SMPR used and applied appropriately in the supporting documentation (manuscripts, method studies, etc...)? If not, please explain the differences and if the method is impacted by the difference. 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. 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. 1. Based on the supporting information, were there any additional steps in the evaluation of the method that indicated the need for any additional precautionary statements in the method? 2. Does the method contain system suitability tests or controls as specified by the SMPR? If not, please indicate if there is a need for such tests or controls and which ones. 3. Is there information demonstrating that the method system suitability tests and controls as specified in the SMPR worked appropriately and as expected? If no, please specify. 3. Is there information demonstrating that the

% ABV is not used appropriately. As mentioned before, the calculation described in the method manuscript for %ABV from ug/mL does not contain a conversion for weight of ethanol to a volume. This introduces an error into the results reported for the method validation samples. For example, the spikes prepared for LOQ validation were stated to be .05%, but are actually .063% ABV when converting ethanol to a volume using density at 20C.

Yes, accuracy and reproducibility criteria were met using reference materials for LOQ and accuracy determinations.

Reference materials were used in the validation of the method LOQ and across the specified analytical range. However, calculation of ethanol concentration appears to have been based on weight rather than volume. This impacts demonstration of method performance in that samples prepared to validate LOQ were >.05% ABV. However, based on the data presented, I feel that the method would perform adequately for samples spiked at .05% ABV. Thus only the calculation of %ABV in the method needs to be modified.

No

The method contains a system suitability test for blanks and a mid-level check standard. A requirement for a low level-check standard should be included per the SMPR.

Yes, the data presented indicated worked as appropriately and as expected. No significant level of ethanol was detected in the blanks and the mid-level check standards fell within the required 90-110% specified in the method manuscript.