By Dr Simon Cichello, B. Agric. Sc. (Hon), LLB, PhD in nutrition and food science, and a SAI Global lead food safety auditor. Dr Cichello is Managing Director of Wholesale Group International Pty Ltd, the Australian supplier of OxySorb™ oxygen absorbers.
Rice, flour, oats, dried beans and other dry grains are among the foods people most often pack for longer pantry storage in Australia. An oxygen absorber can help protect quality in a suitable sealed barrier pack by lowering residual oxygen, which otherwise contributes to rancidity and to loss of flavour and colour. It is not a substitute for starting with dry, sound food, or for packaging that actually keeps oxygen out.
This page explains a conservative way to pack those foods at home or in a small workplace. It is not a validated commercial shelf-life study and it does not give a guaranteed storage life in years.
Start with food that is already dry enough
Oxygen absorbers remove oxygen. They do not dry food, and they do not make moist food safe. Pack only suitably dry rice, flour, rolled oats, dried beans, lentils or pasta. Freshly cooked grains, damp flour, and any food that still feels moist or warm from processing are not suitable for this general method.
Removing oxygen from a pack that is not dry enough can create conditions in which some dangerous bacteria grow. That risk is one reason commercial moist or semi-dry foods need a validated process, not a general internet chart.
Choose packaging that is a real oxygen barrier
Use foil-laminate (Mylar) bags, other proven oxygen-barrier pouches, or clean glass or metal containers with sound seals. An ordinary supermarket zip bag is not necessarily a long-term oxygen barrier, even if it can be closed again.
A barrier bag without an absorber still holds the oxygen that was in the air when you sealed it. An absorber in a leaking bag will keep working until it is exhausted. The two parts of the system have to be used together. For bag sizing, see oxygen absorbers for Mylar bags or use the Ask OxySorb™ calculator.
A conservative starting size for common containers
Air is about 21% oxygen. As a conservative starting point, allow about 250 cc of absorber capacity per litre of sealed container volume. That is the same rule used in our size guide. Bulky pieces (whole beans, pasta) trap more air than a tightly filled bag of white rice, so do not calculate from the visible headspace alone.
| Typical container (filled to the seal) | Conservative starting capacity | Example OxySorb choice |
|---|---|---|
| Up to 1.2 L jar or small bag | 300 cc | 300 cc |
| Up to 2 L bag or jar | 500 cc | 500 cc |
| Up to 4 L bag or bucket liner | 1000 cc | 1000 cc |
| Up to 8 L bag or pail liner | 2000 cc | 2000 cc |
You can combine sachets to reach the total. For larger bags, spread them through the food. Open the supply pack only when the containers are ready, work promptly, and reseal unused sachets in oxygen-barrier packaging.
Rice, flour and whole grains are not all the same
White rice and polished grains are usually more stable in storage than brown rice or other whole grains, because the bran layer contains oil that can go rancid. Wholemeal and other whole-grain flours similarly contain more residual oil than highly refined white flour. An oxygen absorber and a good barrier pack can help slow oxidative change; they do not turn a high-oil food into a low-oil one, and they do not replace cool, dark, dry storage.
Flour and grain can also carry insect eggs. A clean container, a sound seal, and storing the sealed pack inside a rigid bin or bucket if rodents or pantry moths are a risk, are part of the system. Freezing a newly purchased bag of flour or grain before packing is a method some households use to reduce insect risk; it is a handling choice, not a claim about OxySorb performance, and the food must be dry and back at room temperature in a low-humidity space before absorbers are added.
How to pack a bag or jar
- Use clean, dry containers and dry food that has cooled fully if it was recently dried or frozen.
- Fill bags or jars, leaving enough room for a reliable heat seal or lid seal, and label the contents and the pack date.
- Add the chosen OxySorb sachet or sachets and seal immediately.
- Check the seal. Store the packs somewhere cool, dry and away from sunlight.
- Inspect later for puffed bags, damaged seals, off odours or any sign of moisture, and do not use a pack you are not confident about.
OxySorb sachets are specified as food-contact packaging accessories, with manufacturer analysis by SGS Laboratories in Shanghai and stated compliance with AS 2070:1999. Sachets are printed “Oxygen Absorber” and “Do Not Eat” in English. Keep them away from children and pets, and do not open, eat, microwave or try to reuse them.
Frequently asked questions
Can I store rice and flour with oxygen absorbers?
Yes, when the food is suitably dry and is packed in a genuine oxygen-barrier bag or container with a reliable seal. Use the conservative 250 cc per litre starting rule, or the Ask OxySorb™ calculator, and treat this as a quality-protection method, not a guaranteed number of years of shelf life.
Does brown rice last as long as white rice in a Mylar bag?
Not necessarily. Brown rice and other whole grains retain bran oil, which can go rancid sooner than polished white rice. An oxygen absorber can help, but it does not change the composition of the grain. Keep expectations conservative and store packs cool and dark.
Should I put a desiccant in with the rice or flour as well?
Only if you also need to manage moisture, and only after checking that the absorber and desiccant are compatible. They do different jobs. See oxygen absorber vs desiccant.
What size sachet should I buy for a 5 L or 10 L grain bag?
As a conservative start, 5 litres would be about 1250 cc of capacity (for example one 1000 cc and one 300 cc, or similar) and 10 litres about 2500 cc (for example one 2000 cc and one 500 cc). Measure your actual filled volume if you can, then choose sachets from the OxySorb range.
Next steps
Shop OxySorb 20 cc to 2000 cc, read the Mylar bag guide, or contact us about a commercial pack. A one-hour packaging consultation is available if you need application-specific advice.
This page is a starting guide, not a shelf-life specification or a guarantee. Oxygen absorbers do not perform in every packaging system. It remains the customer’s responsibility to confirm that the sachet and packaging are suitable for their food, and to test a small sample first. To the extent permitted by law, Wholesale Group International Pty Ltd is not liable for loss arising from use of this information. OxySorb is a trademark of Wholesale Group International Pty Ltd.