One of the easiest and fastest ways is freezing.
First, rinse the berries and let them dry. Use small resealable bags for freezing.
Fill the bag with clean, dry berries, leaving a little space, and place them in the freezer in a row.
After a few hours, take out the bags, shake them lightly and return them to the freezer: any berries that are stuck or frozen will come off, and your sea buckthorn will be crumbly and easier to pick or divide into portions.