A cartoon from 1864 depicts a solider breaking his tooth on hardtack.

Various forms of unleavened bread have been a survival food around the world for thousands of years.

Hardtack was one particular form of unleavened bread that was a staple ration for sailors and soldiers throughout the 18th and 19th centuries.

Hardtack was considered a superfood ration for a few reasons. It was easy to make a lot of bread at a very low price point, since its only ingredients were flour, salt and water.

Hardtack recipe

Ingredients

• ½ cup of flour
• 1 tablespoon of salt
• ¼ cup water

Directions

For two biscuits (you won’t want more than that), mix together the flour with the salt. 

Add the water and mix until your biscuits feel like cookie dough.

Bake for 20 to 30 minutes at 375 degrees and see how your own ‘biscuit bricks’ turned out.

To make them easy to store on a ship and to ensure they lasted a long time, hardtack was baked for so long that it was essentially a “biscuit brick.” With next to no moisture inside of it, hardtack would last indefinitely if it was stored in the right conditions.

In fact, some of the hardtack that was used during the Civil War was actually leftover from Mexican-American War rations more than a decade before.

Traditional hardtack was so dense, sailors would sometimes use it as a plate for their meal. It was difficult to eat it plain without losing a tooth. Usually sailors would crumble the biscuits into their soup, coffee or fry them in leftover fat to try to improve the flavor.

Hardtack biscuits accumulated a lot of nicknames over the years, including “tooth dullers,” “molar breakers,” “sheet iron,” and, most infamously, “worm castles.”

Hypothetically hardtack never went bad if stored properly, but sailors struggled to keep it safe from the constant moisture that surrounded a ship sailing in the middle of the ocean.

If the mold didn’t get it first, rations would be full of worms, maggots or weevils. It wasn’t uncommon to have to bang your biscuit on the side of the table and watch all the bugs skitter out before you enjoyed your dinner.

Another strategy was to dunk your hardtack in hot water and scoop the floating bugs off the top.

It’s not hard to believe that there aren’t a lot of nutrients in a biscuit made solely from flour, salt and water. The common ideology behind nutrition in the 1700s and 1800s was radically different from what we know today.

Hardtack was a staple of sailors’ diets most days, and all that mattered was that they eat enough biscuits to feel full. Many sailors faced the ravages of scurvy until it was discovered that incorporating vitamin-C into their diets could dramatically improve their experiences at sea.

It’s not known by the same name anymore, but hardtack can still be found as a survival food — particularly in Alaska and Hawaii.

Now referred to as “pilot bread,” or “pilot crackers,” hardtack was introduced to both areas by whaling and merchant vessels traveling through the area. The recipe has changed slightly to make the biscuits a little softer to bite, but the main idea is the same.

Attempting your own hardtack could be a great experiment as we head into the holidays and baking season is upon us.