Long-Term Food Preservation

Long-term food preservation is about getting food to last MONTHS to DECADES rather than days to weeks. The primary methods each target different food types and different storage goals: dehydrating, canning (water bath + pressure), freeze-drying, salt curing, and mylar bag storage.

Each method has tradeoffs. Canning is cheap and familiar but heavy and glass-breakable. Dehydrating saves weight but degrades nutrients. Freeze-drying is the gold standard for 25-year storage but requires expensive equipment. Mylar bag storage of dry goods is the most accessible for beginners.

Method comparison

• ☐ DEHYDRATING — removes moisture, 1-5 year shelf life, works for fruit/veggies/jerky
• ☐ WATER BATH CANNING — high-acid foods only (jams, pickles, tomatoes), 1-2 years
• ☐ PRESSURE CANNING — low-acid foods (meats, beans, vegetables), 1-2 years, botulism risk if done wrong
• ☐ FREEZE-DRYING — 25+ year shelf life, lightest weight, expensive equipment
• ☐ MYLAR BAG + OXYGEN ABSORBERS — dry goods (rice, beans, flour), 20-30 year shelf life
• ☐ SALT CURING — traditional meat preservation, long shelf life, high sodium content
• ☐ VACUUM SEALING — extends refrigerator/freezer life but NOT shelf stable alone
• ☐ FERMENTATION — sauerkraut, kimchi, pickles — preserved by beneficial bacteria

Mylar bags + oxygen absorbers are the easiest entry into long-term food storage. Rice, beans, flour, pasta, sugar, and oats stored this way last 20-30 years. The equipment is cheap ($30 for bags + absorbers), the skill is simple, and the results are proven.

The method: fill mylar bag with dry food, drop in oxygen absorbers, seal with a clothes iron. The oxygen absorbers remove oxygen from the sealed bag, preventing oxidation, rancidity, and insect survival. Store bags in food-grade buckets for rodent protection.

Mylar bag storage protocol

• ☐ 5-mil or 7-mil mylar bags (Gallon or 1-quart size most common)  → Buy
• ☐ Oxygen absorbers (300cc for gallon bag, 100cc for quart)  → Buy
• ☐ Fill the bag leaving 2 inches at the top for sealing
• ☐ Drop in oxygen absorbers (check dose on package)
• ☐ Squeeze out excess air
• ☐ Seal with a clothes iron or impulse sealer
• ☐ Label with contents and date
• ☐ Store in a food-grade 5-gallon bucket for rodent protection
• ☐ Store in a cool, dark place (55-70°F ideal)
• ☐ Dry goods only: rice, beans, pasta, flour, sugar, oats, dehydrated foods

Pressure canning is the ONLY safe method for canning low-acid foods (meats, poultry, fish, beans, most vegetables). Water bath canning these foods is dangerous — Clostridium botulinum spores survive boiling temperatures and produce deadly botulism toxin in the anaerobic jar.

The technology is not hard but the precision matters. Wrong pressure, wrong time, wrong altitude adjustment = botulism risk. Use only USDA-tested recipes (National Center for Home Food Preservation or Ball Canning Guide). Never improvise canning times.

Pressure canning essentials

• ☐ Pressure canner (Presto or All-American, 16-23 quart size)  → Buy
• ☐ Canning jars (Ball or Kerr, new lids, reusable rings)
• ☐ Jar lifter, magnetic lid wand, bubble remover
• ☐ Canning funnel
• ☐ ONLY use USDA-tested recipes from nchfp.uga.edu or Ball Canning Guide
• ☐ ALTITUDE ADJUSTMENT mandatory above 1,000 ft (PSI changes by elevation)
• ☐ Below 1,000 ft: 10 PSI; 1,001-3,000 ft: 11 PSI; 3,001-5,000 ft: 12 PSI; 5,001-7,000 ft: 13 PSI; above 7,000 ft: 14 PSI
• ☐ Process meats at 10-11 PSI for 75-90 minutes per pint, 90 minutes quart
• ☐ Test seal by pressing center of lid — firm and concave = sealed
• ☐ Label with contents and date — store in cool dark place
• ☐ Use within 1-2 years for best quality (still safe longer)

Dehydrating removes the water from food so bacteria cannot grow. Done at home with an electric dehydrator or an oven set low. Results: dried fruit, jerky, dehydrated vegetables, herbs. Shelf life 1-5 years properly stored.

The key is complete drying — any remaining moisture allows mold. Test dried food by breaking a piece: if it bends or feels spongy, it is not fully dehydrated. If it snaps crisply, it is ready.

Dehydrating basics

• ☐ Electric dehydrator (Excalibur or NESCO)  → Buy
• ☐ Oven method: set to 150-170°F with door cracked open (slow, less even)
• ☐ Slice fruits and vegetables thin and uniform (1/4 to 1/2 inch)
• ☐ Meat jerky: lean beef, pork, or poultry, sliced 1/4" with grain or against
• ☐ Marinate meat 12-24 hours before dehydrating for flavor
• ☐ Dry fruits for 6-12 hours, veggies 8-14, meat 6-10 at 160-165°F
• ☐ Test for dryness: snap test for fruits, leathery-but-not-soft for jerky
• ☐ Store in airtight containers or mylar bags with oxygen absorbers
• ☐ Shelf life: 1 year at room temp, 2-5 years cool/dry

A complete food preservation kit covers all the primary methods. Total investment is $200-500 depending on how serious you get, but it pays back over years of storing food you produce or buy in bulk.

Complete preservation kit

• ☐ Pressure canner + jars for canning  → Buy
• ☐ Water bath canner for high-acid foods
• ☐ Food dehydrator  → Buy
• ☐ Mylar bags + oxygen absorbers for dry goods  → Buy
• ☐ Clothes iron or impulse sealer for mylar sealing
• ☐ Food-grade 5-gallon buckets for bulk storage
• ☐ pH test strips for verifying acidity
• ☐ Canning funnel, jar lifter, bubble remover
• ☐ Ball Canning Guide or USDA canning handbook (reference)
• ☐ Labels and permanent marker
• ☐ Optional: Freeze-dryer (Harvest Right) for 25-year storage ($2000+)