Vacuum-sealing

There are two distinct types of vacuum-sealing machines. The first is the external, dry-pump, direct-extraction units otherwise referred to as domestic or home vacuum-sealers. These machines require special channel pouches, which have formed ridges in one side. The food is placed inside a channel pouch and then the open end of the pouch is placed into the front of the vacuum machine. The cover is pressed down and air is drawn directly from the top of the pouch while the weight of the pouch is supported with the other hand or sits on the bench. These units are very effective at removing the air from the pouch, but also have the drawback of sucking out powders and liquids from the pouch at the same time. This can be overcome by freezing liquids into ice cubes to add to the pouches and allowing them to naturally defrost once the pouch is sealed. Alternatively, pouches with liquids can be placed in the freezer for an hour to allow the liquids to freeze slightly before sealing the pouch—this method is helpful for moist foods, such as seafood or marinades.