Are Mylar Bags Food Grade and Safe for Storing Food?

Mylar bags sold for storing food are labelled food grade and safe for food storage, and that label is the thing to look for before you buy. The bags in the range sold for this purpose are described as protecting their contents against oxygen, heat, pests, light and moisture, which is why they suit dry staples such as rice, pasta, flour and pulses¹. They come in sizes from a small pouch up to a large bag, and most are both zip-lock and heat sealable, so you can choose a reusable closure or a permanent seal².

The safety question has two parts. First, is the material safe to put food in? The seller states plainly that its bags are food grade and safe for food storage, and that is the claim to check on any bag you buy⁴. Second, will the food keep? That depends on what you put in, how dry it is, how well you seal it and where you store it. A bag is a barrier, not a preservative: it holds off oxygen, light and pests, but it cannot rescue damp food or a poor seal.

For an ordinary household, the practical answer is to buy bags labelled food grade, match the size to the food, seal them properly and store them cool and dry. Always check the food's own label for how it should be stored, as Food Standards Scotland advises⁵. If you are building a store from scratch, the wider guide to Mylar bags and oxygen absorbers for dry stores sets the method out in full.

What "food grade" on a Mylar bag tells you

"Food grade" is a claim about the material: that it is made to be in contact with food and is safe for that use. On the bags sold for home food storage, the seller states it directly, describing each size as "Food grade, safe for food storage"⁴. The same phrase appears across the range, from the smallest pouch to the largest bag, so you are not trading safety for size³.

It is worth knowing what the claim does not tell you. It does not tell you the bag is airtight once sealed, that it is thick enough for sharp pasta, or that it will keep food for any particular time. Those depend on the closure, the film and how you store it. The seller's own description of what the bags do is the useful companion to the food grade label: they protect against oxygen, heat, pests, light and moisture¹.

Other food-contact products use the same kind of claim, which helps you judge it. A maker of a collapsible canister describes it as food grade for storing and transporting food or supplies⁶. A water bag maker says a food grade coating on the inside ensures safe transport of water⁷. A cooler bag maker says its bags are safe for storing food and drinks with no additional liners needed⁸. In each case the phrase means the material is intended for food contact, and it is the maker or seller making the claim.

For a UK household, the sensible approach is to buy from a seller that states food grade clearly, keep the packaging or listing until you have used the first bag, and treat the claim as the starting point rather than the whole story. If a listing does not say food grade, do not assume it.

Sizes: matching the bag to what you are storing

The range runs from small pouches to very large bags, and the right choice is the one that holds the amount you will actually use. A bag that is far too big leaves air space and wastes an oxygen absorber; one that is too small means opening several bags for a single meal.

The largest bag is genuinely large. One buyer reported filling it with 10kg of rice and finding plenty of space for more¹. That is a customer's experience rather than a specification, but it gives a sense of scale: if you are storing a few kilos at a time, a medium heavy duty bag is likely to be more manageable. The large bag is sold in pack sizes of 10, 50, 100 and 350, so it is aimed at bulk storage¹. The small pouch comes in pack sizes from 1 up to 2,000, which suits someone buying a few for spices or a group buying in bulk⁹.

If you are unsure which size fits a given weight of rice, pasta or beans, the guide to what size Mylar bag you need for rice, pasta and beans works through the common amounts.

Storing dried food in Mylar bags with oxygen absorbers

The method is simple: dry food, a food grade bag, an oxygen absorber, a good seal and a cool, dark, dry place. The seller states that foods sealed in Mylar bags with oxygen absorbers can last for decades, and that inorganic products such as paper and plastic last even longer¹⁵. That is the seller's claim for its own bags, and it depends on the food being dry and the seal being sound.

A bundle sold for the purpose pairs a heavy duty bag with oxygen absorbers, and one buyer reported using the bags for 3kg of pasta and finding them easy to handle and seal¹⁶. That is a customer's experience, not a guarantee, but it shows the size working for a common household amount.

1. Choose a bag sized to the amount of food you are packing⁴.
2. Make sure the food is thoroughly dry. Mylar bags are for dry foodstuffs, not fresh or moist food¹.
3. Add an oxygen absorber sized to the bag and the amount of food, following the seller's bundle guidance where one is supplied¹⁶.
4. Press out excess air, then seal. Heat seal for long storage, or close the zip for a bag you will reopen².
5. Label the bag with the contents and the date, and store it cool, dark and dry¹.

The protection the bag gives is against oxygen, heat, pests, light and moisture¹. That list explains why the storage place matters as much as the bag: a sealed bag in a hot shed still sits in heat, and a bag on a damp floor still sits in moisture. Keep the store cool and dry, and off the floor if your area floods. The guide to keeping a long-term store cool, dry and free of pests covers the conditions in detail.

Ziplock or heat-sealed: choosing a closure

Most bags in the range are both zip-lock and heat sealable, so the choice is not either-or². The zip is a reusable closure for a bag you open often; the heat seal is a permanent closure for a bag you are putting away. For long storage, heat seal the bag above the zip, so you can still open it with the zip once the top is cut off.

The seller's instruction for its stand-up bag is specific: if you only use part of the contents, ensure the resealing strip is clear of any food or debris to ensure a good seal when reusing it³. That applies to any zip bag. A crumb trapped in the strip lets air in, and air is what the bag is meant to keep out.

If you do not have a heat sealer, you can still use the zip, and there are other ways to close a bag. The guide to how to seal Mylar bags without a heat sealer sets out the options. Whichever closure you use, check it before the bag goes into store.

Heavy duty bags and stand-up pouches: what each is for

"Heavy duty" is the seller's description of a thicker bag in its range, not a regulated standard. The heavy duty bags are listed as food grade and safe for food storage, and the seller describes its largest heavy duty bag as the largest, thickest and most durable Mylar bag available worldwide¹⁷. Treat that as the seller's claim for its own product. The practical point is that a thicker film resists punctures from sharp pasta edges, seeds and dehydrated pieces better than a thin one, which is why heavy duty bags are recommended for heavy, bulky or irregular shaped foods⁴.

Stand-up pouches are a different shape rather than a different material. They are food grade and safe for food storage, and they stand upright on a shelf, which suits powders, supplements, herbs, spices and liquids¹². They have a zip-lock and heat-sealable closure³. They are less suited to filling with bulky rice or pasta because the base is narrow, so use them for the small, awkward items and flat bags for the bulk.

If you are weighing bags against another container, the comparison of Mylar bags or glass jars for dry food sets the two side by side. A glass jar with an airtight lid, such as a push-top jar with a silicone gasket, is a reusable option for a working supply, while a Mylar bag is a single-use barrier for long storage¹⁸.

Which foods suit Mylar bags, and which do not

Mylar bags suit dry food. The seller's lists of uses are consistent across sizes: rice, pasta, noodles, flour, cereals, oats, grains, beans, pulses, seeds, dehydrated meat and vegetables, herbs, spices, salt, sugar, flavourings, tea, coffee and powdered milk¹. The small pouch adds baby milk formula to its list⁹.

What they do not suit is anything moist, fresh or cooked. The bags are described as protecting against moisture, not as preserving wet food, and the seller's uses are all dry foodstuffs¹. Always check the food's own label for how it should be stored, as Food Standards Scotland advises⁵. If you are storing baby formula, follow the maker's instructions on the tin for making it up and keeping it.

For the wider question of what belongs in a store cupboard, the guide to what to keep in an emergency store cupboard and the guide to rice, pasta, oats and pulses for long-term storage cover the staples in detail. If you are storing for a specific diet, the guide to emergency food for medical, religious and allergy diets explains what to check.

Checking a seal before the bag goes into store

A seal you have not checked is a guess. Check every bag before it goes on the shelf, and check again when you open it.

• Look at the seam. A heat seal should be continuous and flat, with no gaps or wrinkles.
• Press the zip. Run a finger along the resealing strip to clear any food or debris, as the seller instructs³.
• Squeeze the bag gently. A sound seal holds the air you press out; a failing one lets it back in.
• Seal again if in doubt. A second seam above the first costs little and removes the doubt.
• Label and date. Write the contents and the packing date on the bag so you use the oldest first.

If a bag fails, move the contents to a fresh bag rather than taping or clipping it. The guide to how long food lasts in Mylar bags with oxygen absorbers explains what affects keeping time, and the guide to rotating your store: first in, first out explains how to use the oldest bags first.