Vlasic puts pickles in PET pasteurizable jar

Vlasic Foods International (Cherry Hill, NJ) is test-marketing the first-ever food product pasteurized in a polyethylene terephthalate (PET) container. Vlasic is currently testing three pickle varieties in a 24-oz widemouth, 82-mm jar supplied by Schmalbach-Lubeca, Plastic Containers USA (Manchester, MI).

The Vlasic jar is the first commercial application of S-L's True Heat Set technology, which allows pasteurization, during which a container can be exposed to temperatures of up to 215°F. Schmalbach-Lubeca has filed for 12 patents related to the technology.

Michael Hodges, director of sales, food products, for Schmalbach-Lubeca, explains the challenge of producing a PET container for pasteurized food: "In traditional hot-fill applications, the product is cooked and then filled into the container at approximately 185°F. Cooling follows which creates a vacuum. In pasteurization, product is filled at ambient temperature and then heated after it is placed in the container. The challenge is to produce a container that can withstand the added pressure created during the cooking process plus the vacuum which is the end result of the cooling cycle."

The container, which is pasteurized at around 215°F, employs vacuum-paneled sidewalls, a champagne-style base and a crystallized neck finish. By controlling the level of crystallinity, the True Heat Set process creates a container with a high degree of thermal stability in the sidewalls, says Hodges.

Additionally, the crystallized finish provides the thermal and mechanical stability to ensure seal integrity throughout the extreme processing conditions. Moreover, the champagne base withstands the pressure created during the pasteurization process.

Schmalbach-Lubeca reports that its True Heat Set process can provide thermal stability at up to 250°F in retort applications.

The jar is topped with an 82-mm polypropylene continuous-thread closure that incorporates an induction-sealed foil liner. The vacuum-holding closure is supplied by White Cap (Downers Grove, IL), a subsidiary of Schmalbach-Lubeca.

The widemouth PET pickle jar, which reportedly has what S-L calls an "adequate" shelf-life of about up to a year, is injection stretch blow-molded and weighs 64 grams. It, of course, features the traditional benefits over glass such as lighter weight and shatter resistance.

For more information: Schmalbach-Lubeca, Plastic Containers USA, Tel: 734-4428-4515, Fax: 734-428-4622

Edited by Bill Noone
Managing Editor, PackagingNetwork.com
bnoone@packagingnetwork.com