MAP or vacuum, and what each buys
Gas flush, or modified atmosphere packaging, replaces the air in the pack with a gas mix chosen for the product. Vacuum plus gas draws the air out first and then backfills, which removes more of the residual oxygen. MAP is the usual choice where the pack has to look full and the product should not be compressed. Vacuum plus gas earns its place where oxygen sensitivity is the whole point. Both are only as good as the seal holding them in.
