Putting sweet potatoes in water serves several purposes that can benefit both the quality and storage life of the vegetable. Sweet potatoes are a popular root vegetable that are enjoyed around the world, but require some special care to keep them fresh and usable for as long as possible. By submerging sweet potatoes in water, key benefits can be achieved:
Curing Sweet Potatoes
After harvest, sweet potatoes must be cured. This process helps heal any wounds on the vegetable while also toughening up the skin. To cure sweet potatoes, they are traditionally kept in a warm, humid environment for 5-7 days immediately after harvest. This curing period allows a thin layer to form on the exterior of the sweet potato to seal in moisture.
Placing freshly harvested sweet potatoes in water can achieve a similar curing effect. The water helps maintain humidity around the vegetables while also providing a clean, controlled environment. Leaving sweet potatoes in water for a few days post-harvest can cure them just as effectively as traditional curing methods.
Hydrating Sweet Potatoes
In addition to curing, soaking sweet potatoes in water helps rehydrate them. Sweet potatoes can lose moisture easily during storage due to transpiration. Placing them in water for 1-2 hours before cooking or eating can significantly increase their moisture content and restore any hydration lost during storage.
This rehydration improves the texture of the flesh, making it less fibrous or stringy. It also enhances the sweet flavor, as more moisture allows the starches to convert to sugars more effectively when cooked. Hydrating sweet potatoes helps them become tender, sweet, and pleasant tasting.
Preventing Spoilage
Perhaps most importantly, keeping sweet potatoes in water prevents spoilage and extends their shelf life. The high moisture content of submerged storage inhibits microbial growth, slowing mold, fermentation, and other spoilage.
The water acts as a barrier against exposure to air, which oxidizes the flesh faster. By keeping the sweet potato underwater, oxidation is minimized, maintaining freshness. The cool temperature of refrigerated water also further slows metabolic activity.
Delaying Sprouting
Sweet potatoes have the ability to sprout new shoots and roots if left in warm, humid conditions. This natural growth response can diminish quality and flavor. By submerging sweet potatoes in water, sprouting is delayed since the water chills the vegetable and limits oxygen availability.
For long-term storage, changing the water every 3-5 days will continue inhibiting sprouting for months. The anaerobic underwater environment effectively presses pause on the sweet potato’s need to propagate.
How to Store Sweet Potatoes in Water
If you want to enjoy the benefits of water storage for your sweet potatoes, follow these simple steps:
Harvesting
Harvest sweet potatoes only when fully mature. Use gloves to prevent skin damage. Avoid bruising or injuring the tubers. Time harvesting 2-3 weeks after vines start dying back. Cure freshly harvested sweet potatoes for 5-7 days in a dark, humid location around 85°F.
Preparation
Once cured, wash each sweet potato thoroughly under cool running water. Gently rub off any remaining dirt but do not scrub. Dry them with a clean towel and remove any roots, stems, or bruises with a knife.
Storage Container
Choose a food-safe plastic container or bucket large enough to submerge your sweet potatoes fully. Glass jars or bowls also work well. Avoid reactive metals like aluminum. Clean and sanitize the container before use.
Water
Use cool, clean water. Tap water is fine. Change the water every 3-5 days. The volume of water should be 3-4 times the volume of potatoes to ensure full submersion. A lid can help block light but is not mandatory.
Temperature
Refrigerate the container of sweet potatoes and water at 45-55°F. Colder temperatures risk chilling injury. Warmer conditions increase microbial growth. The refrigerator’s crisper drawer is an ideal storage spot.
Duration
Most sweet potatoes will store well this way for 4-6 months. Inspect regularly and remove any that show signs of mold or softening. Replenish the water level as needed.
| Sweet Potato Storage Tips | Benefits |
|---|---|
| Harvest mature tubers and cure for 5-7 days | Heals wounds, toughens skin |
| Wash, dry, and prep potatoes | Removes dirt and damage |
| Submerge fully in cool clean water in a container | Maintains humidity and moisture |
| Refrigerate between 45-55°F | Slows spoilage |
| Change water every 3-5 days | Prevents microbial growth |
| Store for 4-6 months maximum | Extends shelf life significantly |
The Science Behind Water Storage
The beneficial effects of water storage for sweet potatoes can be explained scientifically:
Curing
Curing allows lignification to occur. This is the process of lignin deposition in cell walls that water facilitates. Lignin is a complex polymer that rigidifies and strengthens plant cell walls. Curing with water triggers lignin formation, improving skin toughness.
Hydration
Osmosis causes water influx into sweet potato cells when immersed, raising internal moisture content. This reverses the transpiration that gradually dehydrates the tubers during storage. Rehydration enables various cellular enzymes to function optimally.
Slowing Microbial Growth
Microbes require oxygen, warmer temperatures, and lower water activity for proliferation. Submersion restricts microbial access to oxygen while chilling temperature and increasing moisture content to minimize growth.
Preventing Oxidation
Oxygen oxidation of cell components causes enzymatic browning of cut surfaces, damaging color and flavor. By providing a barrier to air exposure, less oxidation can occur. Anaerobic conditions prevent polyphenol oxidase browning reactions.
Delaying Sprouting
Sprouting is an energy-intensive process requiring favorable growing conditions. Cool water storage restricts gas exchange, depletes starch reserves via anaerobic respiration, and lowers tuber metabolic activity. This effectively suspends the cellular processes behind sprouting.
Potential Problems
Despite its advantages, water storage does come with some potential downsides to be aware of:
– Increased chance of bacterial or fungal growth in unclean water
– Requires more space than dry storage methods
– Tubers can become waterlogged if left submerged too long
– Condensation and high humidity encourage spoilage organism growth
– Temperature control is essential – chill injury occurs below 45°F
– Varieties with less natural wax coverage may lose moisturefaster
Proper harvesting, storage preparation, container hygiene, temperature regulation, and water changing is necessary to minimize these risks. Avoiding damage and using only high-quality, unbruised sweet potatoes further reduces the chance of complications.
Frequently Asked Questions
How long can I store sweet potatoes in water?
Most sweet potatoes can be kept successfully in water for 4-6 months if stored properly. Ensure cool temperatures around 50°F, clean water, and intact, high-quality tubers. Change water every 5 days maximum. Discard any that become soft or smell bad.
Do you need to cure sweet potatoes before water storage?
Yes, it is highly recommended to cure freshly harvested sweet potatoes for 5-7 days at 85°F and 80-90% humidity prior to water storage. Curing heals wounds and toughens the skin. Uncured sweet potatoes are more prone to mold growth and moisture loss in water.
What temperature should the water be for storing sweet potatoes?
Maintain refrigerated temperatures between 45-55°F. Any colder risks chilling injury, while warmer permits microbial growth. The refrigerator’s crisper drawer provides an ideal chilled environment. Use a thermometer to monitor.
Does the variety of sweet potato affect water storage?
Yes. Drier, starchier varieties with tougher skin tend to store better long-term underwater. Moist, soft-fleshed types are more prone to mold growth. Red-skinned sweet potatoes also stay fresher than orange varieties. Test different types to see which store best.
Should I keep sweet potatoes in water in light or darkness?
Darkness is better to prevent sprouting and greening from light exposure. A container with a lid or opaque sides is ideal. If using a clear jar, wrap it in a dark bag or paper. Light accelerates starch and sugar conversions as well as sprout growth.
Conclusion
Storing sweet potatoes in water can significantly extend their freshness for months past traditional shelf life. The moisture and cool temperatures prevent sprouting, delay wrinkling and shriveling, and inhibit microbial action. Curing sweet potatoes properly before submersion allows the vegetable’s skin to toughen up.
While water storage requires more space than dry curing methods, the benefits of prolonged quality and edibility are substantial. With the right harvesting, preparation, container, and maintenance, soaked sweet potatoes can offer great taste and nutrition for many months after pulling them from the ground. This simple storage trick lets anyone enjoy delicious, tender tubers year-round.