For oxygen-sensitive drinks — juice, beer, tea, some dairy — plain PET may not hold quality for the full target shelf life. Barrier options close that gap; the trick is matching the barrier to the product so you do not over-spec.
Why barrier matters
Two things age a PET-packed drink: oxygen creeping IN (it oxidises juice, beer and vitamins) and, for CSD, CO₂ leaking OUT. Plain monolayer PET is a modest barrier — fine for water and short-shelf CSD, marginal for long-shelf juice or beer.
The main options
Passive multilayer — a barrier polymer (e.g. nylon MXD6 or EVOH) sandwiched in the wall slows gas transfer. Active oxygen scavenger — an additive blended into the preform actively absorbs O₂. Coatings — a thin internal or external layer (plasma SiOx / carbon) applied after blowing. Each adds cost and can affect recyclability.
Match barrier to the product
Still water: none. Short-shelf CSD: monolayer at the right weight. Long-shelf juice, dairy or tea: passive or active barrier. Beer or highly sensitive: high barrier (multilayer plus scavenger or coating). Over-specifying barrier wastes cost and complicates recycling.
Spec it with Delta
Barrier choice ties to preform weight, neck and fill process — validate the base preform in the Preform–Bottle Advisor, see fill options in the hot / cold / aseptic guide, then state your shelf-life target in the Smart RFQ so Delta El Nile engineering recommends the barrier route.