Two patties were placed side by side on polystyrene
trays (Bush Brothers Inc., Champaign, IL) identified and
placed in a freezer (40 C). After 1 h in the freezer, the trays were
over-wrapped with polyvinylchloride (PVC) film (oxygen transmission
rate ¼ 1627.9 cc/m2/day; moisture vapor transmission
rate ¼ 170.5 g/m2/day).