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Three Keys to Better Vacuum Sealing

After vacuum sealing for years in the test kitchen, we've learned a lot of tricks along the way.

Vacuum sealing food for storage can greatly improve shelf life and help maintain ­quality—but only when done properly. Poorly sealed bags allow oxygen to contact food, speeding spoilage and freezer burn. We do a lot of vacuum sealing here in the test kitchen and over the years have found a few tricks to make it more foolproof.

FREEZE LIQUIDS FIRST:  We generally try to avoid liquids when vacuum sealing as they are notoriously problematic for all but the very best machines. If you have to do it, we recommend freezing the liquid before sealing the bag. Place the bag in a loaf pan (to provide stability in the freezer) and pour in the soup or broth. Transfer the loaf pan and bag to the freezer and freeze until firm. Remove the bag from the loaf pan and vacuum-seal.

COVER BONES:  We often vacuum-seal large roasts for freezing, but protruding bones can easily puncture the bag during vacuuming or storage. To prevent this, use plastic wrap to secure a layer of parchment paper to the bones, effectively blunting them.

FOLD BAGS:  When loading food into vacuum bags, it can be difficult to keep the cut end of the bag free of grease and moisture, two enemies of a proper seal. To guarantee a clean sealing edge, fold back the last 2 to 3 inches of the bag into a cuff. Once the food is in the bag, simply unfold the cuff and seal.

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