Slicing corned beef throughout the grain is a way used to realize extra tender and flavorful slices of meat. The grain of the meat refers back to the route of the muscle fibers. If you lower towards the grain, you’re slicing perpendicular to the fibers, which makes them shorter and fewer robust.
There are a number of advantages to chopping corned beef throughout the grain. First, it makes the meat extra tender. If you lower with the grain, you’re primarily pulling the muscle fibers aside, which might make the meat robust and chewy. Slicing towards the grain shortens the muscle fibers, making them simpler to chew.