How Many Oxygen Absorbers Do I Need?
Use roughly 300cc of oxygen absorber per gallon of dry food. A 1-gallon mylar bag needs about 300cc, a 5-gallon bag about 1500cc. Rounding up is fine; too few leaves oxygen behind.
The simple rule
Oxygen absorbers are rated in cc, the volume of oxygen they remove. The guideline is about 300cc per gallon of dry food. Since dry goods have air gaps, this covers the oxygen in and around the food.
By bag size
A 1-gallon bag needs ~300cc; a 5-gallon bag ~1500cc. You can use one large absorber or several smaller ones that add up, for example five 300cc absorbers for a 5-gallon bag. Rounding up slightly is fine and safer than too little.
Keep spares fresh
Absorbers start working the moment they meet air, so seal any unused ones in an airtight jar immediately. If they feel warm or hard, they have already been used up. Buy in bulk but store spares well.
Frequently asked questions
What happens if I use too few oxygen absorbers?
Leftover oxygen lets food stale faster and can allow pests or mould to survive, shortening shelf life. Using slightly more than needed is safe and ensures oxygen is fully removed.
How do I store leftover oxygen absorbers?
Seal them in an airtight jar or vacuum bag right away, since they activate on contact with air. Properly stored, spares stay usable; exposed ones expire within hours.