Can I keep the opened can in the fridge with a plastic lid?

For a few hours nothing dramatic happens, but it is not correct storage. The lid is not airtight, the food stays against cut metal and it absorbs fridge odours. Decanting into glass or steel takes ten seconds, extends storage life and reduces the chance the next meal is refused.

How long can the bowl stay out in summer?

Far less than in winter. With the house above 25 °C the food enters the danger zone quickly: half an hour is a prudent limit. If your animal eats slowly, serve smaller portions more often instead of leaving a large one available for hours.

Can I freeze single serve portions?

Yes, and for large packs it is the best answer. Split the leftover on the day of opening into meal sized portions, seal them in freezer safe containers and write the date. Always thaw in the fridge overnight: thawing at room temperature brings the surface into the danger zone while the centre is still frozen.

My cat only eats warm food: is that fussiness?

No, it is consistent with how cats assess food. Aromas are released better near body temperature, and a cat with a reduced appetite is far more sensitive to that detail. Warming slightly is a legitimate strategy, as long as the temperature is checked and the portion is not warmed twice.

Can I mix dry and wet in the same bowl?

You can, but the bowl then follows the rules for wet food, not for dry: the added moisture creates the same conditions bacteria like. Mix only the amount that will be eaten immediately and remove whatever is left.

Practical feeding10 minLevel: BeginnerUpdated on July 30, 2026

Storing opened wet pet food safely

How to decant, label, refrigerate and warm wet food after opening, with times, temperatures and clear signs for when to throw leftovers away.

Audience: Pet owners
Species: Dog, Cat
Scope: Valid everywhere

What you need before you start

Un contenitore di vetro o acciaio con coperchio a chiusura ermetica, di dimensione vicina alla porzione avanzata
Un termometro da frigorifero, per sapere davvero a che temperatura lavora il tuo
Etichette adesive e un pennarello indelebile per scrivere data e ora di apertura
Un cucchiaio o una spatola dedicati, lavati dopo ogni uso e non usati per altro

A can of wet food is a sterile product for as long as it stays closed. The moment you open it, it becomes a fresh food that is high in water and protein, which makes it one of the most favourable substrates for bacterial growth in the whole kitchen. From then on three things matter: how quickly it gets cold, what container it sits in, and how long it stays in the bowl before it is eaten. This guide is not about which food to choose or how much to serve: it covers handling after opening only, with the temperatures to respect, the maximum times, and the signals that mean a leftover has to be thrown out rather than rescued.

What happens the moment you open the pack

Opening lets in oxygen, bacteria from the room and, if the bowl is brought back near the container, bacteria from the animal's mouth. Oxygen starts fat oxidation, which is less dangerous than contamination but makes the food unpleasant and can lead to a refused meal. Bacteria follow temperature instead: between 5 and 60 °C, the band food safety guidance calls the danger zone, multiplication is fast.

Every practical rule follows from that: minimise the time the food spends between 5 and 60 °C, make sure the cold is real and verified, and use a container that limits contact with air. Your nose is not a measuring instrument: food can already carry a heavy bacterial load and still smell normal.

The minimum kit and why it has to be that kit

A glass or stainless steel container: non porous surfaces that do not hold odours or soak up fat the way scratched plastic does.
An airtight lid rather than cling film: film lets air through and falls off inside the fridge.
A container close in size to the leftover: less trapped air, less oxidation.
A fridge thermometer: many domestic fridges run above 4 °C, especially in the door shelf.
Labels and a marker: with no date written down, after two days nobody remembers when the can was opened.
A dedicated spoon: scooping with the utensil that touched the bowl carries bacteria back into the container.

The six step procedure

Wash your hands and set the container out before opening
The container should already be dry and open on the worktop. Every extra minute the food spends at room temperature is time inside the danger zone, so the sequence is prepared in advance rather than improvised.
Weigh the serving straight away
Take the meal portion out and put it in the bowl. Doing the portion first and the transfer second stops you returning a container to the fridge that you have already opened twice.
Decant the leftover and seal it
Move the whole leftover into the container, level it off to reduce air pockets and close the lid. Do not leave food in the can: the cut rim is sharp and exposed metal speeds up the loss of flavour.
Write the date and time on the label
Note the date and time of opening on the label, plus the name of the food if several are in circulation at home. The maximum storage time starts from that moment, not from the moment you remember it.
Put the container in the coldest part of the fridge
The middle or bottom shelf, never the door, where temperature swings with every opening. Check with the thermometer that the fridge sits between 0 and 4 °C and adjust it if it does not.
Freeze whatever you will not use in time
If the pack is large compared with the ration, split the leftover into single meal portions immediately and freeze whatever falls outside the time on the label. Freezing after two days in the fridge does not restore quality already lost: freeze on day one.

Times and temperatures to respect

The times printed on the pack take precedence over any general table, because they depend on the formulation and on the heat treatment the manufacturer applied. The table below is for when the label says nothing, and as a reminder for the rest of the domestic chain.

Condition, working reference and note
Condition	Reference	Note
Fridge temperature	0 to 4 °C	Verified with a thermometer, not with the dial
Leftover decanted and covered in the fridge	The time printed on the label	Where nothing is stated, no more than 48 hours
Portion served and left in the bowl	30 to 60 minutes	Less in summer or in a warm home, then remove and wash
Danger zone for bacterial growth	5 to 60 °C	Time spent inside this band must be kept to a minimum
Single portions in the freezer	1 to 3 months	Beyond that safety holds up but quality does not
Thawing	In the fridge, overnight	Never on the worktop and never in hot water

Serving at the right temperature without ruining it

Food straight from the fridge is less palatable, because cold suppresses the release of aroma molecules, and it is less well tolerated by animals with a sensitive stomach. The most acceptable temperature is close to body temperature, around 38 °C: lukewarm on your wrist, never hot.

Preferred method: take the portion out of the fridge and let it stand in the bowl for ten minutes, or rest the closed container in a mug of warm water.
If you use a microwave, heat for a few seconds only, stir thoroughly and test with a finger in several spots: microwaves create hot spots that can scald the mouth.
Never reheat the same portion twice: anything left after warming is discarded.
Do not add boiling water to soften it: that changes the texture and breaks down the structure of the product.
Wash the bowl with hot water and detergent after every wet meal: the residual film of fat holds bacteria even when the bowl looks clean.

When a leftover has to go in the bin

Sign, meaning and decision
Sign	Meaning	Decision
Sharp, sour or rancid smell	Fat oxidation or bacterial growth	Discard, do not mask it with other food
Slimy or stringy surface	A bacterial biofilm forming	Discard and wash the container at high temperature
Colour shifting towards grey or green	Advanced spoilage	Discard without tasting
No opening date written down	Storage time unknown	Discard: doubt counts as an expired date
Left out of the fridge for hours	Prolonged time in the danger zone	Discard even if it looks normal
Sudden refusal of a well liked food	Often the first clue of spoilage	Check the pack and do not push the meal

If the animal has eaten a doubtful leftover and then shows repeated vomiting, bloody diarrhoea, dullness or fever, the assessment is veterinary, not domestic. Take the packaging with you, batch code and expiry included: it is the only way to make a report useful and to link the clinical picture to a specific product.

Frequently asked questions

Can I keep the opened can in the fridge with a plastic lid?: For a few hours nothing dramatic happens, but it is not correct storage. The lid is not airtight, the food stays against cut metal and it absorbs fridge odours. Decanting into glass or steel takes ten seconds, extends storage life and reduces the chance the next meal is refused.
How long can the bowl stay out in summer?: Far less than in winter. With the house above 25 °C the food enters the danger zone quickly: half an hour is a prudent limit. If your animal eats slowly, serve smaller portions more often instead of leaving a large one available for hours.
Can I freeze single serve portions?: Yes, and for large packs it is the best answer. Split the leftover on the day of opening into meal sized portions, seal them in freezer safe containers and write the date. Always thaw in the fridge overnight: thawing at room temperature brings the surface into the danger zone while the centre is still frozen.
My cat only eats warm food: is that fussiness?: No, it is consistent with how cats assess food. Aromas are released better near body temperature, and a cat with a reduced appetite is far more sensitive to that detail. Warming slightly is a legitimate strategy, as long as the temperature is checked and the portion is not warmed twice.
Can I mix dry and wet in the same bowl?: You can, but the bowl then follows the rules for wet food, not for dry: the added moisture creates the same conditions bacteria like. Mix only the amount that will be eaten immediately and remove whatever is left.

What to do next

Set out the container and label before you open anything, weigh the serving, decant the leftover into glass or steel straight away and write the date and time on it. Keep the fridge between 0 and 4 °C, verified with a thermometer, take the bowl away after an hour at most, and freeze on day one whatever you will not use. When the date is in doubt, bin it: a leftover costs far less than a bout of gastroenteritis.