Have followed this procedure for may year with excellent results!
https://www.backpackingchef.com/
“Backpackers often call dehydrated ground beef “gravel” because it doesn’t rehydrate well. Solve this problem by adding bread crumbs to the meat before cooking it. Bread crumbs allow more liquid to penetrate the dried meat when you rehydrate it, so it turns out tender every time.
Use only lean or extra lean ground beef with fat content in the 7% to 15% range. Ground beef with 15% fat content is often labeled as Ground Round. Ground beef labeled as Chuck or Hamburger will have higher fat content. Grass fed beef is usually in the 7% to 10% range.
Some of the fat in the ground beef gets removed when you cook it. Some fat beads up on the surface of the meat while drying. Blot off the fat from the meat with paper towels after cooking and a couple of times while it dries. Starting with low fat meat and blotting off what you can during cooking and drying will minimize any risk of the meat spoiling after it is dried.
For each pound of beef, sprinkle ½ cup of finely ground bread crumbs over the meat. Work the bread crumbs into the raw meat with your fingers. Make bread crumbs by dehydrating bread slices for two to three hours and then grinding the dried bread in a food processor.
Break the meat into small pieces and cook in a frying pan over medium high heat until lightly browned and fully cooked, stirring continuously. Remove from heat and squeeze between paper towels to remove moisture.
Spread small pieces of ground beef on dehydrator trays covered with Excalibur Paraflexx® sheets, parchment paper or the fruit leather inserts that go with your dehydrator. Using non-stick sheets keeps small pieces of dried beef from falling through the trays.
Dry at 145° for approximately six hours. Ground beef will be hard when dry.
Once or twice during the drying process, move the meat around and squeeze with a paper towel to remove oil. Wipe any oil off the non-stick sheets. Break any pieces of meat that are drying slower than the rest in half.”