in the label is a barrier layer of either siox or aluminum oxide that gives the retorted polypropylene container a twoyear shelf life.  topping the container is a seamedon steel lid with an easyopen ringpull feature.  all filling lines are same except minor modifications to the seaming rolls were required.  the ability of the backflushed gas to inhibit bacteria growth is diminished, the &ldquonew&rdquo co 2 released by the pad becomes a supplemental bacteria inhibitor. sourcehttpwww.packworld.compackagefeatureshelflifenothingfishyaboutclearsardinesp…
