Full vacuum crushes soft and crisp foods. You have three options.
Use pulse or gentle mode
Pulse lets you stop the vacuum the moment the bag tightens. Taste of Home sealed saltines in the Avid Armor USV32 without cracking using its gentle pulse. The Nesco VS-12 also has gentle and pulse controls.
Freeze first
Freeze bread slices or a loaf on a tray until firm, then seal. Frozen bread holds its shape.
Skip the vacuum
For chips, just heat-seal the bag without vacuuming to keep them fresh.
