Stella and Chewy, raw pet food manufacturer, upgrades radio communications

Stella and Chewy is a premium pet food manufacturer, focused on a minimally processed, raw diet for dogs. It sells product frozen, freeze-dried or lightly baked and coated with a raw product made during the freeze-drying process.

Mark Sheard, plant engineer at Stella and Chewy, has worked at the facility for almost eight years, and before that, for more than a decade, he worked in human food production. “They are very similar processes,” from a regulatory standpoint to certifications and safety issues to the equipment and OEMs, Sheard says. “So many of those things cross over between the two industries.”

One of those crossover points is the challenge of keeping maintenance, operations, and management in contact to ensure hiccup-free production and rapid responses to any problems on the plant floor. Sheard and his team have started to overcome those challenges with a new radio communication system that enables workers to share real-time information with each other, from voice and text to images and alerts.

The production process and maintenance focus

The pet food production process is very similar to typical meat production. “We bring in frozen block ingredients. We go through a grind step, where we create our different recipes or diets,” Sheard says. The product goes through a clipping process to make 15-pound sausage chubs. The product then goes to a high-pressure processing (HPP) machine for sterilization. “Since we’re raw, we don’t cook, where you’d normally use heat to kill bacteria,” he adds. The raw meat is subjected to 86,000 PSI of pressure, which kills any bacteria.

The HPP is the plant’s most technical machine. “Anytime you’re subjecting a piece of equipment to that many pounds of pressure, it’s cycle-based maintenance,” he adds. The machine does experience failures and leaks occasionally, and there’s a lot attention on that piece of equipment. “From a safety factor, there’s a lot of responsibility that goes with that,” Sheard says.

Then, the product moves to the forming department, where it is pumped into a die to create different shapes. “We can change those dies out for the different shapes we make,” Sheard says. Next, some product is frozen in a spiral freezer, packed frozen, and sold that way. The freeze-dried product goes onto pans and into freeze dryers.

“The freeze-drying process is creating an environment below the triple point of water, so the water going directly from a solid to a gas, and drying all that moisture out of the product. You lose about 75% of your weight in that product in that process. Product comes out very light and shelf stable at that point,” Sheard says.

All of the product at the plant is sorted to guarantee a premium product, looking for any type of foreign material, defects, or broken pieces. “Then, we go through a finished goods packaging. We package in a variety of different sizes,” Sheard says.

Product goes through an automatic scale system for measurement, then an automatic bagging system. “We do a nitrogen injection, like a modified air packaging system for longer shelf life,” he adds. Then, product gets checked again, weighed, metal detected, boxed up, and sent out the door.

“We don’t have any finished goods warehousing on-site. That’s all done through third-party warehousing,” Sheard says.

Production, for the most part, runs two shifts, then a third shift sanitation cycle. The plant does have some processes that run longer. The freeze dryers run between 14 and 20 hours, depending on the recipe. The plant runs 45 different freeze dryers in batches. They load and unload three dryers with product every hour, running 24/7. The sorting department for those finished goods and the panning department that fills trays before freeze drying also run seven days a week. “From a maintenance perspective, I’ve got mechanics on 24/7 coverage, supporting the operations group,” Sheard says.

Every night the entire production area goes through a washdown. Even with NEMA 4X-rated equipment, “Water and electronics never get along,” Sheard says. “We try to keep fighting fires to a minimum and focus on the preventive maintenance.”