No, just pour it in. If you haven't added sulfite and sorbate, you may need to pasteurize it later to prevent the yeast from eating the sugar.
Pasteurization is typically done at two different stages. Cider mills pasteurize cider and juice to kill any wild yeast and other beasties that are in the juice. Cidermakers rarely pasteurize unfermented juice. Cidermakers sometimes pasteurize bottled cider or just before bottling to kill any yeast. Backsweetening a cider will often restart fermentation unless you do something to prevent the yeast from eating the added sugar. Adding sulfite and sorbate, pasteurization, and sterile filtering are a few of the methods.
