[ARCHIVE ANSWER]
As an experiment, you can try freezing a package under normal pressure (ambient air). Then, see how long it takes to "swell" back to normal or have a noticeable pressure increase back in ambient air. Compare that to vacuumed packaging in ambient air.
See which takes longer to expand.
Now, a paste is a good idea. The only real difference between a solvent and a fatty oily substance like peanut butter is the speed at which transportation of the molecules occur. One is a low viscosity liquid and the other is a high viscosity "liquid."