​​W.T. and WinnieShamrock’s rich heritage began when W.T. McClelland (Mr. Mac), son of an Irish farmer, immigrated to the U.S. and bought a small dairy business in 1922 to serve a handful of customers in the Tucson area. His wife, Sara Winifred (Winnie) became the bookkeeper and christened the new business Shamrock Dairy. Together, Mr. Mac and Winnie forged an American success story.

After World War II, Shamrock Dairy built a processing plant in Phoenix and launched continuous expansion programs in both facility development and product line. Over the years, the product line has emerged to include frozen foods, fresh fruits and vegetables, meats, fish and institutional foodservice supplies and equipment.

Today, Shamrock Foods Company is the umbrella for Shamrock Farms, the largest dairy in the Southwest, and Shamrock Foods, a nationally-ranked foodservice distributor. Now headquartered in Phoenix, Shamrock sends refrigerated trucks to 9 other states from distribution centers in Phoenix, Arizona, Commerce City (Denver), Colorado and Albuquerque, New Mexico, and Eastvale, California.

Some Interesting Milestones in Shamrock’s History

War constraints reduce milk delivery schedules to alternate days and daytimes only.

The company’s first Employees’ Retirement and Profit Sharing Plan is instituted.

Shamrock Dairy’s first refrigerated truck is purchased.

A 10-acre building site is purchased on Black Canyon Highway for $50,000.

Shamrock Dairy moves from Tucson to Phoenix and builds its new plant.

Shamrock’s product line is expanded to include ice cream products.

In February, Shamrock Foods division is launched with the transport of fresh produce to northern California, Oregon, and Washington and the back hauling of frozen foods. In April, the house-to-house retail distribution of Phoenix’s Foremost Dairy becomes part of Shamrock.

National Commission Company of Colorado Springs is acquired from Harvey Klunder and ultimately becomes known as Inland National Foods.

United Food Service, Shamrock’s biggest Colorado acquisition, is merged with Inland to form Inland United Food Service, signaling the beginning of foodservice.

Shamrock is cited as a “Great Distributor Organization” by Institutional Distribution magazine, which devotes 13 articles in its June issue to the Shamrock “success story.”

Shamrock’s first mega warehouse opens in Commerce City, Colorado, and the name Inland United Food Service is changed to Shamrock Foods.

Shamrock becomes number one in sales volume for privately owned companies in Arizona, according to Arthur Andersen compiled statistics based on 1986 revenues.

Jensen Foods of Brighton, Colorado, is purchased.
Sharoff Foodservice acquired, Colorado Springs CO.
Booth Fisheries Distribution Center acquired, Denver, CO.

A new addition expands the Commerce City, Colorado, warehouse from 3,750,000 feet to 9,000,250 cubic feet.

Kent McClelland becomes president and chief operating officer of Shamrock Foods.

Shamrock Foods Company is listed among Forbes magazine’s top 400 private companies in the United States for the first time.

Once again, Shamrock is named a “Great Distributor Organization” by Institutional Distribution magazine.

Shamrock’s Arizona Foods Division begins shipping from its fully automated ASRS warehouse.

Shamrock Farms opens a new Extended Shelf Life (ESL) facility that allows us to produce milk beverages (32oz & smaller) that stay fresher, longer. As a result, you'll now find our delicious mmmmilks in vending machines, restaurants, theatres, baseball parks, and more.

Shamrock Foods Foodservice Divisions introduce a new foodservice logo; Corporate office staff moves to a new location in Phoenix; Shamrock Farms moves its entire herd of 10,000 cows into a new state-of-the-art farm in Stanfield, Arizona. Shamrock Farms is one of the largest dairy farms in the United States.

Shamrock Farms Farm Tour will be a fun, educational experience that takes students and families inside the state-of-the-art dairy farm our cows call home. Hands-on lessons cover such topics as how cows produce milk, how dairy technology has evolved, Shamrock's history in Arizona, and more.

Shamrock Foods Company celebrates an 85-year history of excellence and introduces its Organic line of milk and dairy products. The Dairy Division's single-serve ESL (extended shelf life) milk products are now distributed in all 50 U.S. states through the Subway restaurant organization.
In Albuquerque, the New Mexico Foods Division moves into its new 180,000 square foot distribution facility on the city's west side.

The Colorado Foods Division celebrated the opening of its own USDA-certified meat plant, with custom-cut beef, poultry, pork, and lamb products.

Shamrock Foods Company completed construction of a new corporate headquarters facility at 3900 E. Camelback Road in Phoenix.

In August Shamrock Foods opened a new foodservice distribution warehouse in Eastvale, officially expanding Shamrock Foods into southern California. The distribution center is intended to service California's Inland-Empire and south to San Diego.