How to Store Dry Dog Food So the Last Scoop Is as Good as the First

Most dog owners do the same thing with a new bag of kibble. They cut the top off, pour the whole lot into a plastic bin, and throw the bag away. It looks tidy and it keeps the dog out. It also throws away the two things the bag was doing for the food: the packaging the manufacturer tested its shelf life in, and the only printed record of which batch the dog is eating.

The FDA's Center for Veterinary Medicine and Tufts University's Cummings School both say the same thing first: keep dry food in its original bag. Most of what follows comes back to that instruction.

The bag is doing more work than it looks

Lisa Freeman, a board-certified veterinary nutritionist writing for Tufts' Petfoodology service, puts it plainly: many manufacturers put a lot of research into packaging and test the shelf life of the food in that original packaging. Tufts adds that the bag helps keep out pests and other contamination and helps protect the nutrients in the food from breaking down. Pouring kibble into an open-topped bin throws that protection away and exposes every piece to the air at once.

Air is the first problem. Tufts notes that exposure to air causes nutrients in dry food to break down faster and can expose the food to bacteria in the environment. Heat and humidity speed the same process up, which is why the temperature rule below matters as much as the container.

The bag's second job matters on a bad day. The FDA points out that the original bag keeps the UPC code, the lot number, the product name and manufacturer, and the "best by" date to hand in case of a defect or a recall. Less than half of the pet food complaints FDA receives include the lot number, and the lot number is what lets the agency trace when and where a food was made.

Where to keep it: cool, dry and off the floor

Both the FDA and Tufts give the same ceiling. Store dry food somewhere cool and dry, below 80F. The FDA says excess heat or moisture can cause the nutrients to break down. Tufts adds that high temperature and humidity also give mould and bacteria the conditions they need, and that fats in the food can go rancid.

That rules out a few common spots. The Pet Food Institute, the trade body for US pet food makers, specifically advises against leaving the bag on the floor of a garage or outside. A garage in a Texas August, a utility room next to a tumble dryer or a cupboard above the oven can all sit above 80F for long stretches. Cold is a problem too: Tufts advises against storing pet food outdoors where it can freeze.

Get the bag off the floor as well. Tufts recommends it to keep pests away, and the Pet Food Institute suggests checking the container for insect activity between bags.

The right way to use a storage bin

A lidded bin is still worth having, because it keeps a determined dog and pests away from the food. The point is what goes in it.

Put the whole bag in the bin. This is the arrangement both the FDA and Tufts prefer: the food stays in its original packaging, the packaging sits inside an airtight container, and the label stays with the food. Squeeze the air out of the bag and close it with its own seal, a bag clip or tape before the lid goes on.

If the kibble has to be poured, save the label. The FDA says a container used this way must be clean, dry and fitted with a snug lid. Cut out the panel with the UPC code, lot number, product name and "best by" date, and tape it to the outside of the bin. Tufts suggests a phone photo of the same panels as a backup. Replace the label with every new bag.

Empty and wash the bin between bags. The FDA says to wash and dry the container between finishing one bag and filling it with the next, to get residual fat and crumbs off the surfaces. Tufts is just as direct about topping up: make sure the food already in the container is completely used up before new food goes in, then wash and fully dry it. Pouring a fresh bag over the dregs of the last one leaves the oldest kibble at the bottom of the bin for good.

Setup	Shelf-life protection	Label kept	Main risk
Original bag, rolled and clipped	Manufacturer's tested barrier	Yes	A dog can tear into it
Original bag inside a lidded bin	Barrier plus a second seal	Yes	None of note if the bin is cleaned
Kibble poured into a clean lidded bin	Depends on the bin's seal	Only if taped on	Lost lot number, fat residue if topped up
Kibble poured into an open bin or paper sack	Little	Rarely	Air, humidity and mites

How long an open bag stays good

Two dates matter, and only one is printed. Unopened dry food should be used before the "best by" date on the bag. The CDC's write-up of a 2012 Salmonella outbreak noted that the expected shelf life of dry pet food is generally one year from the date of manufacture, and expected illnesses to continue for months because people still had recalled bags at home.

Once the bag is open, the printed date stops being the useful one. Freeman's recommendation at Tufts is to use an opened bag within two to three months, and to buy smaller bags if a bag routinely lasts longer than that. She notes that storage times vary by product, and that diets high in fish oil usually have a shorter shelf life.

That two-to-three-month window is the practical case for matching bag size to the dog. A 10lb dog on a small-breed formula can take a very long time to finish a 15lb bag, and the small-breed food roundup lists the smaller bag sizes for exactly that reason. To work out how long a bag will last, divide the bag's total calories by the dog's daily calories, which needs the kcal per cup from the label and a daily calorie target worked out properly rather than the feeding chart's top line.

Storage mites: what the studies actually found

Three studies cover storage mites in dry dog food, and they point the same way.

A Spanish study opened ten premium dry dog foods formulated for skin conditions and stored them for six weeks (Brazis and colleagues, Veterinary Dermatology, 2008). Mites were present in one of the ten bags on opening, which shows they can arrive inside sealed packaging. After five weeks in warm, humid conditions chosen to suit mite growth, around 74F and 71% relative humidity, mites were found in nine of the ten.

An Australian study tested nine brands of unopened bags and 20 samples of food stored in homes in Sydney and Canberra (Hibberson and Vogelnest, Australian Veterinary Journal, 2014). At ordinary room conditions, about 73F and 47% humidity, no storage mites were seen in any new-bag sample over six weeks, and none were seen in the household samples either. Moved into an incubator at about 79F and 80% humidity, seven of the nine new-bag samples grew the storage mite Tyrophagus putrescentiae, with mites and then eggs visible after three weeks.

A UK study followed dry food stored three ways in ten households for 90 days (Gill and colleagues, Veterinary Dermatology, 2011). Mites turned up in six of ten paper bags, three of ten sealable plastic bags and one of ten sealable plastic boxes. The authors concluded that sealable plastic boxes largely prevented contamination for three months. They also found house dust carried 10 to 1,000 times more mites than the stored food, and judged the exposure from food to be trivial next to the dust.

Read together, the studies point at warmth and humidity together as the trigger. In these studies, food kept at ordinary room conditions or in a sealed box rarely grew mites within the time it takes to finish a bag, while food held warm and humid grew them within weeks.

The reason anyone cares is allergy. Brazis and colleagues describe storage mites as potentially important allergens in dogs with atopic dermatitis, with high sensitisation rates reported in atopic dogs, and Tufts points out that mite-contaminated food is one of the reasons pets can be wrongly diagnosed with a food allergy. For a dog going through an elimination diet with a vet, a fresh, sealed bag of the trial food removes one variable that could muddy the result.

Hygiene: the bowl, the scoop and the hands

Dry food is not sterile. The 2012 outbreak traced to Diamond Pet Foods' plant in Gaston, South Carolina made 49 people ill with Salmonella Infantis, 47 in the US and two in Canada. Michigan's agriculture department found Salmonella in an unopened bag of Diamond dry dog food during routine retail testing, and investigators matched the human cases to that strain. In interviews, 22 of 28 ill people reported contact with a dog in the week before they got sick. A 2023 outbreak linked to Mid America Pet Food caused seven illnesses in seven states. The CDC notes that most pets carrying Salmonella show no symptoms but can still spread it through their poop and saliva, and that children under five, adults over 65 and people with weakened immune systems are more likely to become seriously ill.

The FDA's handling advice follows from that:

Wash hands with soap and hot water for at least 20 seconds before and after handling pet food.
Wash the food bowl and the scoop with soap and hot water after each use.
Use a dedicated scoop, not the dog's bowl, to take food out of the bag, and keep that scoop for pet food only.
Throw out old or spoiled food in a securely tied plastic bag in a covered bin.

A measuring cup kept as the scoop does a second job too: every meal gets measured rather than poured by eye.

When a food smells wrong or is recalled

The FDA lists a foul odour as one of the signs of a problem with a pet food, and Tufts warns that fats in food kept too warm or humid can turn rancid. Kibble that smells rancid or off, a bag with visible mould, and a bag with insects in it all belong in the trash rather than the bowl. At purchase, the FDA's advice is to skip any bag with tears, dents or discolouration in the packaging.

If a dog becomes ill after eating a food, the FDA's instruction is to stop feeding it and call a vet, then report the problem to both the FDA and the manufacturer. That report is where the lot number and "best by" date come in. For a recalled food, the CDC's advice is to throw it away in a sealed bag inside a sealed bin so wildlife cannot get to it, not to donate it, and to clean the bowls, scoops and surfaces it touched.

Opened wet food is a different rule

Canned and pouched food is not covered by any of the above once it is open. The FDA says to cover and refrigerate leftovers promptly at 40F or below, or throw them out. Tufts says an opened can, even refrigerated, should be discarded after 72 hours. For a dog fed a mix of both, the wet and dry comparison covers what each format changes in the bowl.

The short version

Keep dry dog food in its original bag, with the air pressed out and the top clipped. Put that bag inside a lidded bin if the dog or pests are a problem. Store it below 80F, somewhere dry and off the floor, and never in a hot garage. Finish an opened bag within two to three months, per Tufts, and buy a smaller bag if it lasts longer. If the kibble has to be poured out, tape the lot number and "best by" date to the bin, and wash and dry the bin before refilling it. The label itself is worth reading closely while it is still attached, and the adequacy statement on the back of the bag is the line to start with.

Questions people actually ask

Should I keep dry dog food in the original bag?

Yes. The FDA and Tufts University both recommend keeping dry food in its original bag, because manufacturers test shelf life in that packaging and because the bag carries the lot number and best-by date needed if a food is recalled. Placing the whole bag inside a lidded bin gives a second seal and keeps the dog out.

How long is dry dog food good for after opening?

Tufts' Petfoodology service recommends using an opened bag within two to three months, and buying smaller bags if one routinely lasts longer. Foods high in fish oil usually have a shorter shelf life. Unopened bags should be used before the best-by date printed on the bag.

What temperature should dog food be stored at?

Below 80F, in a cool, dry place, per the FDA and Tufts. Heat and moisture break nutrients down and can turn fats rancid. Avoid garages, sheds and other spots that run hot or can freeze.

Do storage mites in dog food matter?

They can for a dog with allergies. Studies found mites grow readily in kibble kept warm and humid, but rarely at ordinary room conditions, and sealable plastic boxes largely prevented contamination over three months in one UK household study. Tufts notes mite-contaminated food is one reason pets are sometimes wrongly diagnosed with a food allergy, so a dog on an elimination diet should get fresh, sealed food.

Sources

As an Amazon Associate we earn from qualifying purchases. We earn a commission on some links, at no extra cost to you. It never changes which products we recommend or the order they appear in. Full disclosure