BRYARRR_80 I would add that since you are working with large amounts of ground beef it would be well worth your time to experiment with smaller batches (1 lb) and getting the flavor you are after before scaling up the amounts for large batches.
About the pH meter you sell....
What is the storage solution for?
raider2119 At the end of the electrode there is a small cap that you will fill with a small amount of the solution when they are not in use. If you don’t store it in this solution the electrodes will not work the next time you to to use them.