The Long Blue Line: Lt. Juan del Castillo - Guardian of thousands, savior of millions

By William H. Thiesen, Ph.D., Atlantic Area Historian


The Long Blue Line blog series has been publishing Coast Guard history essays for over 15 years. To access hundreds of these service stories, visit the Coast Guard Historian’s Office’s Long Blue Line online archives, located here: THE LONG BLUE LINE ( 

The Coast Guard is a sea service with a variety of missions that attracts personnel with unique talents and experiences. A few examples include Alex Haley, a Coast Guard journalist who became a famous writer after leaving the service, and Dr. Olivia Hooker, the first African American woman to wear a Coast Guard uniform as a World War II SPAR, who became a distinguished psychology professor at Fordham University. 

Juan del Castillo was also a member of the Coast Guard who distinguished himself in the service and in civilian life. 

Born in New York in 1921, he attended La Salle Military Academy in Oakdale, New York, and graduated from Manhattan College in the spring of 1942. In June, he began what became a 40-year career with the Coast Guard Reserve. After first enlisting in the service, he received an appointment to Reserve Officer Training, later known as Officer Candidate School, at the Coast Guard Academy. He completed the course in December 1942, becoming the first Hispanic Coast Guardsman to complete the training and second Hispanic Coast Guard officer. 

It was in the Coast Guard that del Castillo honed his leadership skills. During World War II, he served aboard the 1912 cutter Unalga and the heavily armed patrol craft PC-469, which both served as escorts for convoys in the Caribbean at a time when U-boat attacks there were a common occurrence. He was next selected for Naval Communications School at Harvard University and became an expert in shipboard communications. He served the latter part of World War II in the Aleutian Islands aboard the Coast Guard-manned patrol frigate, USS Albuquerque. 

After the war, del Castillo left active duty, but continued to serve as a Reservist, and took a job with his family’s import business, Rafael del Castillo & Company. During this period in his career, he became interested in famine relief in the developing world. Armed with his bachelor’s degree in political science and his Coast Guard training, del Castillo became a self-taught authority on food science, famine relief and large-scale food aid distribution. 

In later years, while continuing to serve in the Coast Guard Reserve, del Castillo worked in executive positions with the Department of Agriculture (USDA) and the U.S. Agency for International Development (USAID). During this time, he invented the formula for Corn Soy Milk, considered one of the most important high protein foods ever developed. Next, he invented a rice substitute out of sorghum for international food programs. Unlike large commercial food producers, del Castillo developed these highly nutritional food substitutes with no staff or laboratory. Over four million men, women and children worldwide consume these food products daily to avoid malnutrition and starvation. 

As if his important advances in food science were not enough, del Castillo also held leadership positions at the USDA. These included directing distribution of foods for the nation’s school lunch program and elderly and family feeding programs and providing food for American Indian reservations. He also served as the first director of the nation’s food stamp and Women, Infants, and Children (WIC) program. In 1981, after his retirement from the Coast Guard Reserves as a commander, del Castillo continued his work on nutritious food for feeding the needy and starving as he took an additional leadership role in the cause of improved survivor annuities for military widows. 

Juan del Castillo, the Coast Guard officer, war veteran, self-taught scientist and humanitarian passed away in 2009. Before he died, del Castillo was recognized for his important contributions to humanitarian food aid programs with the USAID Lifetime Achievement Award. Commander del Castillo left behind a wife of 57 years, six children and 19 grandchildren. 

Carrying on the family tradition, one of his grandchildren began training as a cadet at the Coast Guard Academy in August 2010; nearly 70 years after del Castillo did as a Reserve Officer trainee. del Castillo was a member of the long blue line and another example of the talented individuals who join the Coast Guard to serve others. 

Image Gallery

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CGD 24 Wainwright Unknown port; photo taken from quarterdeck of unnamed USCG cutter. Boston? Photo...
USCG patrol boats during Prohibition
"Coast Guard Destroyer Downes (From a Painting by the Destroyer Force Bugle Staff Artist, Marius...
"Ensign Roland making end run, Coast Guard-Marine game, Washington, D.C., 1929." Scanned from...
"1929 - Coast Guard Football Team - 1929. Back Row: -Lieut. Baker, Coast and Manager; Wineke,...
A photo of Coast Guard Destroyer CONYNGHAM on patrol during Prohibition.
Coast Guard Destroyer's baseball team (no date).
Hand-written caption on reverse of photo reads: "Officers and crew of CGC Beale (Navy destroyer...
Hand-written caption on reverse of photo reads: "R R Waesche Sr., CGC Snohomish, Port Angeles, or...
"BEALE (CG-9) (Of the old U.S. Coast Guard Destroyer Force - 1924-1930) An early 20th century...
"Engineroom Force of the Coast Guard Cutter PONTCHARTRAIN. 3-5-29 (1)." CCG Scrapbook (CG...
Copy photo found in the CG Historian's Office Special Collections Archive in the "Uniforms" folder....

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