Kombucha ERP

Kombucha Method Re-submission Review Form

Submission Date

2018-09-26 09:53:02

Name

Blake Ebersole

Email

blake@npscientific.com

Organization

NaturPro Scientific

Has the resubmitted method met the requirements outlined on September 24, 2017? Please provide justification for your answer. If specific requirements were made in the September 24 meeting, please explain how those requirements have been met or not met.

Yes

Requirements from First Action were addressed. In particular, the following data is now presented that demonstrates that the method controls for potential interferences from commercial samples.

1. Method accuracy and repeatability of spiked commercial samples was performed.

--23 samples of commercial kombucha were analyzed before and after spiking 4 different concentrations of a known amount of ethanol.

--The repeatability at the higher end of analytical range was 1% RSD with approx. 98% accuracy, and lower end of analytical range was 3% RSD, with accuracy approx. 98%.

2. Precision in kombucha matrix was measured with 13 commercial samples from 6 producers run in duplicate.

--The average % difference in duplicates across all concentrations was approx 5%. --The average % difference in duplicates for 10 of 13 samples with >0.5% ABV was also approx. 5%.

3. Measurement accuracy in matrix was performed by spiking commercial samples with ethanol, in duplicate to 0.5% or 1.5% ABV.

--Percent recovery was 93-104% and percent difference was 0.2-1%