Ever wonder how we make our shelf-stable backpacking meals at Gastro Gnome? What goes on in this kitchen that transforms our home-cooked dishes into delicious, nutritious, lightweight backpacking meals?
It starts with chef-made recipes. The second secret is freeze-drying, a slow, gentle process that locks in the nutrition, flavor, and texture of real food while removing nearly all the water weight.
Here's how it works, and why we think it's the best way to make backpacking food.
How the Freeze-Drying Process Works
When we finish cooking our food, it goes through a multi-step freeze-drying process. First, our food is placed in the deep freezer, where it undergoes the first stage of the freeze-drying process: freezing.
Stage 1: Freezing Backpacking Food
During freezing, the water in the food turns into ice, forming ice crystals throughout the food. Once the food is completely frozen, we transfer it to our freeze-dryer.
Stage 2: Sublimation (Primary Drying)
During this stage, the freeze-dryer creates a low-pressure environment that allows the ice crystals to sublimate, meaning the ice changes directly from a solid into a vapor without passing through a liquid phase. The water vapor is then drawn away from the food through a vacuum. Water collects on the walls of the freeze-drying chamber in the form of ice.
Stage 3: Secondary Drying
Finally, the temperature rises gradually to draw out any remaining moisture. What's left is a lightweight, shelf-stable meal ready for the trail.
Why Freeze-Dried Food Is Better for Backpacking
This lengthy process results in some pretty interesting benefits.
It Rehydrates Fast
First, freeze-drying creates a porous structure as the ice crystals are removed. This porous structure allows water to mix back into the food more easily during rehydration. Researchers have found, for example, that freeze-dried tomatoes rehydrate four times faster than hot-air-dried tomatoes, and six times faster than infrared-dried tomatoes.
Less waiting around camp, more eating.
It Keeps More Nutrition
And importantly, freeze-drying relies on low temperatures compared with other drying methods. This helps preserve many of the vitamins, antioxidants, and other sensitive compounds found in fresh food. Studies show that freeze-dried products maintain a higher level of proteins, carbohydrates, total sugars, and vitamins compared to those processed by solar, room-temperature shaded, hot-air, and microwave drying methods.
It Tastes Like Real Food
Because moisture is removed gently at low temperature and low pressure, freeze-drying helps preserve the food's original structure, color, flavor, and aroma. Your dinner tastes like dinner.
Freeze-Dried vs. Dehydrated Backpacking Food
By contrast, dehydrated food is dried with warm air over several hours. It works, but heat can shrink and toughen food and break down some nutrients, and dehydrated meals usually take longer to rehydrate.
Freeze-dried food skips the heat, making it a gentler process. It keeps its shape, rehydrates faster, and typically holds less leftover moisture, which helps it stay shelf-stable longer. The tradeoff? It's a much slower, more expensive process. We think it's worth it.
High Energy, High Reward
The freeze-drying process can take an exceptionally long time. At Gastro Gnome, our food will remain in the freeze-dryer for approximately 30 to 50 hours, depending on the recipe.
It’s also an energy-intensive process compared with many other drying methods, and is largely recognized as a more challenging process for manufacturing dried products.
So why do we choose it?
Because the extra time and energy are worth it for creating high-quality backpacking meals that taste good and keep us energized.
Freeze-drying is a relatively gentle preservation method. Removing moisture at low temperatures and under low pressure helps preserve the food’s original structure, color, flavor, aroma, and nutritional value.
The result is a lightweight, shelf-stable food that can be rehydrated quickly, without sacrificing the qualities that make a meal enjoyable to eat in the first place.
Cooked, Frozen, and Dried With Care
So the next time you’re tearing into a bag of Gastro Gnome freeze-dried Sausage Rigatoni, remember that every meal has been cooked, frozen, and dried with love and attention to detail to create delicious food to fuel your adventures.
Frequently Asked Questions About Our Backpacking Meals
How long does freeze-dried backpacking food last?
Gastro Gnome meals are shelf-stable for 2 to 4 years (depending on the meal) when stored in a cool, dry place.
How do you rehydrate freeze-dried meals?
Add hot water to the bag, stir, seal, and wait about 8 to 12 minutes. Stir, seal, dig in!
Is freeze-dried food healthy?
Yes! Freeze-drying is one of the gentlest preservation methods, so it keeps more of the protein, vitamins, and nutrients from the original food than most heat-based drying methods.
What's the difference between freeze-dried and dehydrated food?
Dehydrated food is dried with heat. Freeze-dried food is frozen and dried under a vacuum, which keeps more flavor, texture, and nutrition and lets it rehydrate faster.
