Return of the railroad

This piece was written by Union Pacific railroad - and as such it reads at times like a commercial - but it offers a nice history lesson on the evolution of refrigerated transport in the U.S. Considering the steady climb in fuel prices in recent years, the reemergence of rail transport stands to reason if railroads are committed to the service levels required.

Prior to the westward railroad expansion in the United States, food moving cross country was either dried or salted for preservation. As railroads were constructed in the 1800s, agriculture producers saw markets opening for their dairy products, fruits, vegetables and meats. No longer localized, their markets expanded to 50, 100 or even more than 1,000 miles away. Railroads were able to transport most goods, but moving perishable items required development of a specialized rail car that would help keep food fresh or preserved en route.

The first patented refrigerated car was built in 1867. Air, forced over blocks of ice in large compartments on each end of the rail car, kept the perishable commodity cool. For the day, this crude "refrigeration unit" was state-of-the-art.

Ice to fill the rail cars was naturally harvested from lakes and ponds. The ice cakes were stored in insulated buildings next to the tracks.

Union Pacific Railroad constructed huge, long wooden ice houses along its main lines in the late 1800s to provide the ice needed to constantly fill the refrigerated boxcars as they made their way across the country. Moving fresh meat from Kansas City to Los Angeles or strawberries from Los Angeles to Chicago required ice and a lot of it.

But by the 1890s, health complications arose from the use of natural ice, its purity affected by expanding cities’ pollution and sewage dumping into waterways. Refrigeration technology provided the solution: mechanically manufactured ice. Ice as the source of refrigeration in transportation would prove difficult to replace.

Meanwhile, America was hungry for fresh food, and the country’s demand for fresh meats, fruits and vegetables was growing by leaps and bounds. In response, the Southern Pacific and Union Pacific Railroads formed The Pacific Fruit Express Company in 1906.

Ice is king – but not for long

Sometimes as big as a barn, large refrigeration units were developed for commercial use, primarily for breweries, in the 1870s. By 1891, nearly every brewery was equipped with refrigerating machines. Refrigeration units small enough for use in transportation, though, would not be designed until the late 1940s.

In the 1950s, railroads continued to be the transportation mode of choice for fresh fruits and vegetables. But by the ‘60s, aging refrigerated boxcar fleets combined with the completion of the Interstate highway system prompted agricultural producers to shift their time-sensitive shipments to truck.

By the mid-1970s, more and more perishable food was moving by truck. In 1978, Pacific Fruit Express was dissolved and the two companies formed their own perishable transport subsidiaries, Southern Pacific Fruit Express and Union Pacific Fruit Express.

In the mid-1990s, partially as a result of rising fuel costs, but largely the result of better service, the railroads began seeing a resurgence in perishable food transportation. Once again, rail had become an attractive mode of transportation for perishable food items. And with the revival came a redesign of rail cars to handle larger loads and refrigerated units that became more energy efficient.

Union Pacific worked with eastern railroads to offer customers "seamless" service between the West and East coasts. At the same time, UP began to expand and refurbish its refrigerated boxcar fleet.

New breed of refrigerated boxcar

Since 2003, Union Pacific has purchased 1,500 64-foot cars and completed an extensive upgrade of more than 3,500 of its 50-foot cars. Union Pacific handles more than 48,000 shipments of refrigerated and frozen products each year and is the country's largest owner of refrigerated rail cars with more than 5,000 refrigerated cars in the current fleet.

The new reefers can carry more than 50 percent more product than their predecessors. A 64-foot rail car carries as much as four over-the-road trailers. The refrigeration units used in both new and refurbished cars are state-of-the-art and energy efficient. They use the latest technology, such as global positioning satellite (GPS) monitoring, not only to track rail cars’ trip progress but also to check temperature, fresh-air exchange and diagnostics. Fresh-air exchange is an important feature for commodities such as onions that require fresh-air circulation. Temperature variance with the new units is as little as plus/minus two degrees.