How Much Water to Rehydrate Freeze-Dried Food
Enter the food and dry weight to see the most water it can take back.
Weight of the freeze-dried portion you are rehydrating
Advanced settings (finished moisture)
Rehydration Water
117.77 cups (942.2 fl oz)
Start with about half, wait, then add more as needed — this is the most water the food can take back.
Estimates for planning, not food-safety advice. Freeze-drying does not kill bacteria — follow tested food-safety guidance.
To return food to its original weight, add back the water that was removed. 100 g of freeze-dried strawberries can take about 983 g (983 mL, about 4.2 cups) of water. Start with about half, wait a few minutes, then add more as needed.
Worked example
100 g dry strawberries (90.95 % water fresh, 2 % left after drying) → about 983 mL.
How it's calculated
original weight = dry weight × (1 − moisture left) ÷ (1 − water %); water to add = original weight − dry weight. 1 g of water = 1 mL.
Frequently Asked Questions (FAQ)
Do I always add all of it?
No. It is the maximum. Many foods taste better slightly under-hydrated.
Hot or cold water?
Follow your recipe; for meat and eggs, food-safety guidance comes first (see the food-safety page).
Sources
- USDA National Nutrient Database for Standard Reference, Release 28
Water content of the 52 foods (with USDA NDB numbers; Release 28, 2015)
- Utah State University Extension — Ask an Expert: Freeze-Drying Food at Home (May 2026)
Bacteria dormant during freeze-drying, cook meat/eggs, high-fat food safety, preparation
Last reviewed: 2026-10-26
Built and maintained by Numberwright. Water contents come from the USDA nutrient database; every formula and source is listed on this page. Found a mistake? Contact details coming soon.
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