Even with technological advances such as microprocessors and data-recording products to monitor temperatures being introduced to the transportation industry, dairy processors rely on truck refrigeration technology that hasn’t changed much in decades.

Cold-plate refrigeration and its components are more reliable than ever, and dairy processors and transportation companies are gravitating back toward that technology as fuel costs rise. Those who make mechanical refrigeration units praise the low-noise kits and electric standby to help reduce diesel fuel costs — and say they’re better than cold plates in warmer climates.

“Plates are simple, reliable technology. It’s like building a better mousetrap,” says John Cook Jr., vice president of operation at Dole Refrigerating Co., Lewisburg, Tenn. “Plates go from truck body to truck body and there are some plates out there older than me. The reason it works so well is we haven’t monkeyed with it. It’s a proven system, with low maintenance and lower costs.”

The trend in cold plates is that the technology never gets old — it’s been around since 1937 and it still works the same way, Cook says.

“We continue to review to see if there are any ways to improve our Eutectic solution formulas, and yes, we’ve added some fans here and there, but the reality of it is the cold plate is extremely dependable. How many ways are there to freeze an ice cube?” he says. “The only way to improve it more is to freeze the plates going over the road. In the past you’ve needed a 10- to 12-hour dock time.”

Because cold plates chill the air, “according to our customers, if a truck breaks down you have up to two days in which the product’s integrity will be preserved, if you keep the doors closed,” Cook says.

In the South, cold-plate trucks are being phased out in favor of mechanical refrigeration, which requires the engine to be running to make constant refrigeration, says John Chisolm, president of Dallas-based W&B Service Co. “Ideally it’s plugged in for 12 hours and then runs for eight hours. Mechanical refrigerated trucks use diesel, and the fuel is not taxed if it’s used for refrigeration.

“But as fuel costs have gone up, which is an uncontrollable commodity for transportation, some companies are looking at using cold-plate refrigeration. Plates are cyclical. When fuel goes down, then companies will go back to mechanical refrigeration.”

Whether cold-plate or mechanical refrigeration is used, everyone agrees that rising gas prices are spoiling the bottom line. “If gas prices go up and you’re spending more to get the product to your next destination, then you’re spending more on the product,” Cook says.

Electrification is one of the latest trends in cold transport, according to Greg LaFrance, director of sales and marketing, Johnson Refrigerated Truck Bodies, Rice Lake, Wis. “We see more and more products that improve and boost or transform electrical power. These power systems can be used to charge refrigeration systems, compressors lift gates, telematics, et cetera,” LaFrance says. “The key is reducing the demand on diesel-driven engines, therefore reducing emissions and noise levels.”

Johnson recently launched its RouteMax program, with 30 trucks equipped with what the company calls the next generation of cold-plate technology. Trucks equipped with the new technology allow users to charge cold plates as they drive, reducing plug-in time and extending delivery routes.

RouteMax is powered by International Truck and Engine’s PowerPack 3, a self-contained power supply system built into the vehicle that provides continual charge to the cold plates without being a drain on fuel economy.

Although the industry is mature and has already incorporated many of the necessary practices to optimize fleet operation, there is always room for improvement.

“Features in the Thermo King controller like ‘opti-set’ allow the unit to be customized for the customer specification application by programming temperatures most commonly run in the fleet,” says Doug Lenz, director of transport product management at Minneapolis-based Thermo King.

Lenz says he sees greater interest in data-recording products to provide proof of temperature. “And a greater focus is on being more environmental friendly by reducing unit noise through low-noise kits and reducing diesel fuel costs by ordering units with electric standby,” Lenz says. “Dairy processors expect us to continue to maintain the product integrity of the products they deliver by offering a high-capacity, quiet unit that provides the most precise temperature control at the lowest total life-cycle cost.”

Lenz says improved microprocessors with built-in self-diagnostic capabilities continue to improve temperature control, reduce operating costs and improve product shelf life. Microprocessors monitor and download the life of the temperature inside the truck. This accurate recordkeeping means that stores can reject loads based on that information.

“Data loggers tell you everything that’s happened to the temperature versus set point, and can monitor and control temperature,” Chisolm says. “Milk is hauled best at 34 degrees, and every degree above 38 degrees cuts the life of the milk by one-third. If milk lives 21 days, then you’ve just lost one week.”

Jeffrey Caddick, purchasing agent at Hercules Manufacturing Co., Henderson, Ky., offers this scenario: “As a ‘for instance,’ more and more dairies are delivering to Wal-Mart, where a load of milk might be rejected for being one degree above Wal-Mart’s specifications, or a dairy industry driver might be delivering ice cream to Wal-Mart and find the folks receiving his product actually opening up one container of ice cream and rejecting it because they see an insufficient number of ice crystals in that container.”

As such, Caddick sees customers seeking to maximize the amount of foam in a unit to promote better temperature control over longer routes. “We have invested significant amounts of money in advanced foaming technology,” he says.

Because of this trend in the dairy industry, truck buyers want to spec bodies up to broaden potential areas of service and their product capability, Caddick says. “Evidence of this can be seen in dairy industry buyers who are standardizing their specs between locations and companies,” he says. “In going this route, dairy buyers are maximizing their efficiency in a way that most other foodservice companies are not.”

With dairy conglomerates owning more regional brands, each processor may be covering longer distances with their routes, Caddick says, or carrying multiple products or brands, which requires different temperature controls and compartment set-ups. “The bottom line is that a piece of equipment used for one purpose may be put to another purpose the next day,” he says.

Hercules markets heavily to the dairy industry, building milk bodies, ice cream bodies and combo bodies of aluminum sheet and post construction. Its products utilize mechanical or cold-plate refrigeration, with either traditional plates mounted on the wall or ceiling application, or cold-plate blower unit application, with either piston or scroll compressors, Caddick says.

LaFrance says he sees the trend toward larger straight trucks and multi-temperature vehicles that can handle a variety of products. “The standard milk truck five years ago used to be 18 feet. Now, the new standard is becoming 22 feet,” he says. “We also build a fair amount of 24-foot straight trucks, but because of the weight of fluid milk, it requires a tandem chassis which is more expensive.”

Chisolm says with the switch from route trucks to long trailers, case drops have increased tremendously. “You’ll see even larger trailer loads,” he says.

Aging equipment is also a challenge. Caddick says processors commonly run truck bodies through three chassis. Lenz agrees: “Dairy fleets are requiring more flexibility in their fleet utilization and are pressured to extend the life of their trailers an additional one to two years of their typical fleet life.”

Because dairy processors build strong identities for their products, they want their trucks to look the same, Caddick notes. “They spend a good amount of money on vehicle graphics so that the trucks stand out, and make that identity a part of their local communities’ day-to-day lives,” he says. “The dairy industry understands that their advertising dollar doesn’t end when the commercial is over.”  

Shonda Talerico Dudlicek is a freelance journalist and a former managing editor of Dairy Field.