The Bag-in-Box (BIB) packaging solutions specialists at Smurfit Kappa (Epernay, France) have expanded the range of packaging solutions for hot-fill apple juice market with the custom-engineered Thermo Bag.

Hot filling is widely used in the production of fresh, not-from-concentrate apple juice, a method that has grown increasingly popular due to the beverage's freshness and health benefits. During hot filling, the product is pressed, filtered, pasteurized, heated and filled at a high temperature to facilitate sterilization and then immediately cooled for preservation and taste. This method has the advantage of extending shelf life, removing any harmful microorganisms, reducing costs and simplifying the process.

When paired with Bag-in-Box packaging, it becomes an attractive eco-friendly and cost-efficient option for both consumers and producers that maintains product quality.

The innovative Thermo Bag is a barrier bag made from special coextruded polyethylene, medium-density PE (MDPE) for thermo-resistance, linear-low density PE (LDPE) for flexibility and an ethylene vinyl alcohol (EVOH) oxygen barrier.

“Usually apple juice makers heat the juice at 80 to 85 deg C (176 to 185 deg F) for pasteurization,” Smurfit Kappa spokesperson Veronika Necasova (shown) tells PlasticsToday. “This Thermo Bag is perfectly adapted to these high temperatures because it’s more heat-resistant, doesn’t change visually even after heating that could occur with other bags and has less risk of stress-cracking.”

This enhancement doesn’t represent a shelf extension because that mainly depends on the juice itself, she adds.

The use of MDPE in the coextruded structure is unusual in this market.

“It is rarely used in bag-in-box packaging, which is typically made using LDPE,” Necasova explains. “Use of a new film is always a challenge and requires many tests in lab, but also on filling machines. For example, the film has to be slippery enough to be pulled properly through the forming funnel of a bag-forming filling machine.”

The new structure is FDA-compliant for applications in the United States and throughout North America.

“We are not aware of any special approval for apple juice hot filling in North America, although there is one for dairy products,” Necasova points out. “In any case, testing methods are the same, though requirements are lower than in Europe.”

In development for about a year, PlasticsToday learned that the new packaging carries about a two percent premium versus standard BIB bags.

Most of the interest in the new BIB option is expected to come from large companies. “This bag is particularly suitable for bigger companies using high temperatures to fill their apple juice and who require higher quality for their packaging because their juice goes to retail,” Necasova says. “For example, it is being sold in Switzerland, Poland and Sweden.”