How to Freeze Dry Sweet Potatoes at Home

Introduction

Quick refresher, unlike traditional drying methods, freeze drying removes water through a process known as sublimation. This simply means the water tranforms from a solid (ice) directly to a gas (vapor) without passing through a liquid state. And this is what results in lightweight, shelf-stable foods that are perfect for long-term food storage when stored properly. 

So it’s a great option for things like raw sweet potatoes, though you can also process cooked potatoes too! Their rich nutritional profile (& natural sweetness hello) are an excellent candidate for  because the process leaves food with a stronger flavor. Why so? Because you’re only removing the water, not the sugars or anything else like that. So they won’t be muted or diluted. Alright then, let’s add some freeze-dried sweet potatoes to your stores for variety & convenience. 

Preparing Sweet Potatoes for Freeze Drying

Just a note here, this same process would apply to white potatoes too.

1. Select fresh, firm sweet potatoes that don’t have blemishes. And definitely no soft spots! It’s the freshness we’re preserving here so choose the best of the best. Otherwise, you could have poorer quality in the final product. 
2. Wash the sweet potatoes thoroughly under running cold water to remove any dirt or debris. Really give em a good scrub now girl, these are dirt-baked produce items. Not, picked off a tree fruits.
3. Peel the sweet potatoes using a vegetable peeler if you want, but this is optional.
4. Cut the sweet potatoes into uniform slices or cubes. You can freeze dry raw potatoes in any shape but size uniformity is what ensures they freeze dry evenly, preventing some pieces from being over-dried while others remain too moist. 

We enjoy freeze drying sweet potato shreds because they’re exceptionally easy to store that way & make making hash browns a breeze. But you can cut them into french fries to be little sweet & salty snacks later if you sprinkle them with a lil real salt. If you want diced (which is great for adding to soups and such), use a food processor to make light work of it all. 

Alternatively, you could make baked sweet potato. Rub your sweet potatoes with a tiny bit of olive oil, wrap in aluminum foil or set on some parchment paper and roast in the oven for a bit. Once cooled to room temperature, use a potato masher or blender to blitz through these.

That mash will become freeze dried sweet potato powder! Instant sweet potato mash/flakes. Or add as a thickener to chili’s & stews for the perfect texture. It can even go into smoothies.

Blanching Sweet Potatoes

Now let’s get back to how to freeze dry sweet potatoes. 

Blanching may help preserve the color of sweet potatoes during the freeze drying process. This isn’t necessary from a safety stand-point so it’s optional to.

But if you want to, start by bringing a large pot of water to a boil with a few pinches of salt and preparing an ice bath (a large bowl filled with ice and water). Submerge the sweet potato pieces in boiling salted water for 2-3 minutes. This brief cooking time deactivates some enzymes that cause slight discoloration. 

After blanching, quickly dunk those pieces in the ice bath to stop the cooking process. Once cooled, drain the sweet potatoes and pat them dry with a clean towel.

Pre-Freezing Sweet Potatoes

Pre-freezing sweet potatoes before putting them in the freeze dryer is also an optional step. if you have/use a Harvest Right freeze dryer like us, the full cycle includes a phase to freeze food if necessary. But pre-freezing reduces the overall freeze drying time & prevents the pieces from sticking together. It also helps keep that structure and quality during the freeze drying process. I think the only problem is forgetting you stuck them in there! 

So here’s how to do it.

1. Shred, dice or chop your sweet potatoes into even sizes. The size of the potato will affect the drying time. The larger the chunk, the longer it will take to dry.
2. Arrange blanched sweet potato pieces in a single layer on a baking sheet. (Remember, blanching is optional but could help retain that pretty color.) Make sure they don’t touch so that they can freeze evenly. This will also help during the freeze drying process because water can be removed from the many different surface areas. 
3. Place the cookie sheet in the freezer for several hours, or until the sweet potatoes are completely frozen.

When you use a home freeze dryer like a Harvest Right freeze dryer, freeze drying is a straightforward and efficient process. Simply load fresh or pre-frozen sweet potato pieces onto the freeze dryer trays. If you have silicone mats, you can place these down first then your food. Remember to leave your pieces evenly spaced as much as possible and not overcrowded. You should not load them beyond the lip of the tray.

You may need to check the unit’s settings to be sure it’s right for sweet potatoes. Usually there’s a low-temperature freeze (down to -20F even!) which is followed by a gradual increase to allow for sublimation. 

Now, don’t just sit & watch it because the full cycle can take anywhere from 24 to 48 hours. It depends on several things like the model of the freeze dryer, the amount & size of food being processed, the temperature of the room too.

I found that food took longer in our apartment during summer months than it did when it was cooler outside. If you have this somewhere like a basement or well-controlled climate area you should see shorter cycle times. 

Monitor the progress periodically to ensure the machine is functioning correctly and the sweet potatoes are drying uniformly. You’ll know they’re done when they can audibly be heard snapping. Alternatively, you can weigh your filled trays before loading into the freeze-dryer & then measure them afterward before packaging away. This net weight is the amount of water removed & this water content chart may be helpful. So in theory, you can calculate what the net weight should be (close to anyway) once the run is complete. And if you weigh your filled trays & its’ not close, keep drying!

Storing Freeze Dried Sweet Potatoes

After you freeze dry sweet potatoes you need to store them & proper storage is crucial girl. Don’t skip it! This isn’t just some food you can leave in the package on the shelf. 

By the nature of this process, if you don’t store freeze-dried potatoes well, they will take on moisture & rot right where you have ’em. 

Related blog post: How to Store Freeze Dried Foods Long Term

So to maintain the quality & extending the shelf life of your freeze-dried sweet potatoes, skip the plastic bags. Don’t use the resealable freezer bag. Air can get in these. 

I find the best storage options include Mylar bags with oxygen absorbers, vacuum-sealed bags, & airtight containers like a quart jar or pint jar. The Mason jars are nice because you can use a food-grade vacuum sealer with jar attachments to seal them. Or better yet, just a stand alone jar vacuum sealer! 

But I’ll forever love my Mylar bags. They give me an excellent barrier against moisture & UV. When paired with an oxygen absorber (which removes any residual oxygen), my food is further insured against spoiling. So no matter how far down the line, they’ll be ready for later use.

I then store those bags into secondary containers for extra protection. Consider it! Whichever route you choose, label your storage containers with the date and contents to keep track of your inventory. I also recommend jotting this info down in a kitchen logbook. 

Then store the freeze-dried sweet potatoes in a cool, dark place, away from direct sunlight and high temperatures.

Rehydrating Freeze Dried Sweet Potatoes

Rehydrating freeze-dried sweet potatoes is simple.You’re gonna either soak the freeze-dried pieces in warm water (try 1 c water for a some handful or so) until they reach the desired texture. Usually in about 15-20 minutes. OR, you can add them directly to soups, stews, and other recipes where they will absorb that liquid. Just be mindful of that because if you’re going for true soup (not like a chili), you’ll need to make sure they sweet potatoes don’t absorb all that liquid. 

Rehydrated sweet potatoes can be used just like you would fresh or cooked sweet potatoes. Mashed, roasted, casseroled or eaten solo with maybe a lil sea salt or brown sugar. 

Related blog post: How to Rehydrate Freeze Dried Food at Home

Creative Uses for Freeze Dried Sweet Potatoes

Freeze-dried sweet potatoes are incredibly versatile for access to really good food in a lot of ways! You can 

• Eat them straight as a healthy snack or add them into recipes for some hidden nutrient boost. 
• Make sweet potato chips by lightly seasoning and baking the rehydrated pieces,
• Add them to smoothies for a creamy texture, or using them in casseroles and pies. 
• Rehydrate and use as a filling for sweet potato pie or a topping for sweet potato casserole. 

Alright now, everything simple doesn’t necessarily mean it’s easy or without trouble. So although you can freeze dry sweet potatoes pretty straightforward, you might have some issues. This isn’t a full list at all & in fact, there’s a troubleshooting guide from Harvest Right already.

1. If the sweet potatoes aren’t fully drying, ensure that they are cut into uniform pieces and not overcrowded in the freeze dryer. 
2. If the final product has loss flavor or texture, you should take a look at your storage system. And definitely if you see mold or anything like that. An airtigtht container is the best way to go. 
3. Regularly check your stored sweet potatoes for spoilage and repackage them if necessary. I know maybe you preserved it for Doom’s Day, but check (& rotate) through that stuff regularly.

FAQs

🌱 Start Small. Start Now. Start where you are with what you have. The rest will follow. 🌱

If you want to be more self-sufficient, start with your food.
But you don’t have to give up good food to do it!

The Eat Good Food All the Time e-course is here & FREE!

You already know how to eat good food.
Let me show you how to save $$$ doing it.