Self-Reliance · Food
Drying removes enough moisture that microorganisms cannot grow. The equipment is modest and the skill transfers directly to the harvest surplus from a garden.
Temperature guideHow it works
Dehydrating works by removing enough moisture that bacteria, mold, and yeast cannot grow. Most spoilage microorganisms require a water activity above 0.85 to function. A properly dried food drops below this threshold, making it shelf-stable without refrigeration or chemical preservatives.
Drying does not sterilize food the way canning does. Microorganisms present on the food may survive in a dormant state and become active again if the food reabsorbs moisture. This is why proper sealing after drying matters as much as the drying process itself. It also explains why the temperature guidelines for meat are different from those for produce: bacteria on meat require specific heat treatment to be destroyed, not merely suppressed.
The NCHFP at the University of Georgia is the primary authority for home food drying guidance, along with the USDA Food Safety and Inspection Service for meat products.[2]
Temperature guide
These are USDA and NCHFP guidelines, the research-backed standards for safe home drying. Use a dehydrator with an adjustable temperature dial and a built-in or separate thermometer to verify actual temperature.
135°F
Standard drying temperature for most fruits. Slice uniformly for consistent drying. Pretreatment with ascorbic acid (citric acid or lemon juice) prevents browning of light-colored fruits such as apples, pears, and peaches.
Source: NCHFP Drying Fruits and Vegetables
140°F
Slightly higher temperature than fruits. Most vegetables require blanching before dehydrating to inactivate enzymes and improve color and texture.[3] Exceptions include onions, mushrooms, and peppers, which can be dried without blanching.
Source: NCHFP; Michigan State University Extension
95-115°F
Lower temperatures preserve the volatile oils that carry flavor and aroma. Herbs are done when they crumble easily between fingers. Rinse before drying, shake off excess water, and remove any damaged leaves. Spread in a single layer.
Source: NCHFP Drying Herbs
160°F / 165°F first
The USDA Meat and Poultry Hotline requires that beef and pork reach 160°F and poultry reach 165°F before or after the dehydrating step. A dehydrator operating at 130 to 140°F will not reliably achieve these temperatures during the drying process alone. The recommended approach is to heat raw meat in a 275°F oven until it reaches the internal temperature target, then transfer to the dehydrator at 130 to 140°F for drying.[1]
Source: USDA FSIS Jerky Safety. This step is required, not optional.
Storage after drying
Properly dried food stored in poor conditions degrades quickly. The same food stored correctly can last 1 to 5 years or more.
Airtight glass jars or vacuum-sealed bags. Glass mason jars with tight-fitting lids work well for most dried produce. Vacuum sealing extends shelf life further. Avoid containers that allow any moisture exchange. Label with contents and date.
Before sealing dried fruit for long-term storage, "condition" it: pack loosely in a glass jar, leave for 7 to 10 days, and shake daily. If moisture condensation appears, the fruit needs more drying time. This step redistributes residual moisture and helps identify pieces that are not fully dried. Skip for vegetables and herbs.
Cool, dark, and dry. Light degrades color, flavor, and nutritional content. Heat accelerates rancidity. A pantry shelf or basement cabinet away from heat sources works well. Check containers periodically for signs of moisture intrusion, mold, or insect activity.
How dehydrating compares to canning, fermentation, and freezing. Which method fits which food and which household.
Read the guide →
The other major home preservation method. High-acid fruits, jams, tomatoes, and pickles processed in a water-bath canner.
Read the guide →