ESL cap: Portola
A tamper-evident, liner-less plug closure called the Steri-Shield 38mm from Portola Packaging Inc. was designed for extended shelf life and aseptic beverage packages. It is compression-molded using high-density polyethylene and features a taller profile than the non-tamper-evident version. The lightweight closure can withstand an aseptic sterilization environment of up to 140 degrees Fahrenheit. By eliminating liners, package costs are minimized and less material is used. The closures can be made in a variety of sizes ranging from 38 to 43 millimeters, with or without a tamper-evident band. The company has capabilities to produce closures suitable for a wide variety of low- and high-acid aseptic applications.