Interstate Meat Distributors Inc. (Clackamas, OR) processes more than 60 million pounds of ground beef and sausage a year, packaged in case-ready trays, overwrap, fresh patties, IQF patties, and chubs for distribution throughout the western U.S.

Chilling during grinding/blending can dramatically impact the throughput of forming operations, so the chilling system must be carefully matched for batch-to-batch repeatability. Batch grinding/mixing operations also add thermal energy to the product.

CO2 vs Liquid Nitrogen for Food Chilling

Most high-volume processors of ground meat and poultry have been chilling in mixing/blending vessels fitted with carbon dioxide (CO2), the only real choice for bottom-injection (BI) in the U.S. Interstate Meat president Darrin Hoy says Interstate first started using CO2 chilling in the mid-1980s.

While some processors still use CO2 snow horns or pellets, top-chilling methods are inherently less efficient. Top-chill snow horns may require 3X more time and 20-25% more cryogen to achieve the same desired temperature as BI systems.

New BI systems are normally installed with new mixing or forming equipment, though existing mixers even just a few years old can dramatically benefit from retrofits, which typically involve components such as nozzles and vents.

Using Liquid Nitrogen (LIN) for Industrial Food Chilling

Interstate worked with Messer North America to beta-test the liquid-nitrogen (LIN) BI system on one of the plant’s mixers — in this case a 10,000 lbs./hour blender.

Messer application engineers documented existing chilling process parameters and designed a new hygienic nozzle injection system for multiple ports on the blending vessel, in addition to a new exhaust system for the lid to make it a complete, matched system.

“One of the great attributes of the LIN bottom-injection system is you don’t have to mix the meat as long, and a shorter mix time is always better for your end product. You can grind more pounds per hour. There’s less emulsified fat because it’s not as beat up, so it looks better in the package, too,” says Hoy.

The optimized Liquid Nitrogen BI system from Messer cut the chill time in the blender from eight minutes to three.

It equilibrates batches to a target temperature with high batch-to-batch repeatability. Consistent chill temperatures also help keep forming equipment running smoothly and “smear-free.”

Working With Messer for Liquid Nitrogen Food Chilling

“The Messer Food team worked closely with my management on implementation, often after hours to minimize downtime, right down to training all our employees on the new technology. The exhaust system eliminates clouding — and from an environmental and hygienic perspective, everything is better than our CO2 system.”

Messer finalized the LIN BI system on the first mixer in January 2011, and the other production lines followed, with all lines now operating flawlessly for well over a year. The installation included new supply lines to the blenders and a new LIN tank on a pad outside. (The new injection nozzles and venting system can run either CO2 gas or Liquid Nitrogen.)

Messer supplies Interstate from its gas production facility in Vancouver, Washington, and reliable supply was an important part of the equation, Hoy says. Messer is the number one supplier of CO2 gas in North America and a top supplier of N2 through its extensive distribution network.

While cryogen costs vary by region, the production advantages of upgrading to an optimized BI system almost always pay off, and can tilt the scale in favor of liquid nitrogen (LIN) BI. 

Learn more about Messer's freezing and chilling solutions for food processors here.