UC Agriculture and Natural Resources released information on March 9 about various methods for dehydrating food, highlighting the process as an effective way to preserve food by removing most of its moisture. Dehydration inhibits the growth of bacteria, yeasts, and molds that require water to thrive.
The topic is important because dehydration is one of the oldest preservation techniques, dating back thousands of years. It allows people to store lightweight, nutrient-dense foods for long periods, making it useful for seasonal harvests or outdoor activities.
Tim Long, a volunteer with the UC Master Food Preserver Online Program, described several core dehydration methods. Electric dehydrators are considered efficient and reliable due to their controlled temperatures and air circulation. Oven drying is another option but takes longer and uses more energy. Sun drying requires specific weather conditions and is mainly recommended for fruits. Other approaches include air or room drying for herbs and mushrooms, solar drying using greenhouse-like structures, freeze-drying through vacuum processes, and microwave drying for small quantities of herbs.
Long also outlined essential preparation steps such as blanching vegetables to stop spoilage reactions, dipping light-colored fruits in antioxidant solutions to prevent browning, slicing foods evenly for uniform drying, conditioning dried fruit in airtight containers to balance moisture levels, and pasteurizing foods dried outdoors to eliminate insect eggs. Recommended temperatures vary by food type: herbs (95–105°F), vegetables (125–135°F), fruits (135–145°F), and meats (145–160°F). For storage, airtight glass jars or vacuum-sealed pouches kept in cool, dark places are advised; freezing can extend shelf life further.
UC Agriculture and Natural Resources enhances lives statewide by sharing science-based practices according to the official website. The organization maintains nine Research and Extension Centers as living laboratories across diverse ecosystems according to the official website and operates offices in all 58 California counties according to the official website. It applies University of California expertise through research and outreach initiatives according to the official website, supporting communities across California.
Glenda Humiston serves as vice president of UC Agriculture and Natural Resources according to the official website. The organization has provided creative resources in nutrition, food networks, youth education, farming practices, environmental conservation efforts including wildfire protection for over a century according to the official website.
For those interested in learning more about safe home dehydration without specialized equipment or freeze-drying techniques specifically, online training sessions are scheduled via Zoom on April 14 at 7pm and May 19 at 7pm.