Food safety and storage

Storing, cooling, freezing, thawing and preserving food safely.

Best beforeA best before date marks when food is at its best quality, not when it turns unsafe. Food can usually be eaten after it if stored as directed.
Blanch and freezeBlanch and freeze means boiling vegetables briefly, chilling them in ice water, then freezing them. It keeps their color, flavor and texture for months.
BotulismBotulism is a rare but serious illness caused by a toxin that grows in low-acid, airless food, such as badly home-canned vegetables or garlic in oil.
Cooling food safelyCooling food safely means getting hot leftovers cold fast so bacteria cannot grow. Split big batches, use shallow containers and chill within 2 hours.
Cross-contaminationCross-contamination is when germs or allergens spread from one food, surface or hand to another. Separate raw meat, and wash hands, boards and knives.
Danger zoneThe danger zone is the temperature range where bacteria grow fastest, 4 to 60°C (40 to 140°F) in USDA guidance. Keep food out of it as much as you can.
First in, first outFirst in, first out (FIFO) means using your oldest food first. Put new groceries behind older ones so nothing expires at the back of the shelf.
Flash freezeFlash freezing means freezing food in a single layer on a tray before bagging it, so berries, dumplings and cookie dough stay loose and easy to portion.
Freezer burnFreezer burn is the dry, grayish, leathery patches on frozen food left exposed to air. It is safe to eat but tastes and feels worse, so trim it off.
HeadspaceHeadspace is the empty gap between the food and the lid of a jar or container. The right amount helps canning jars seal and stops frozen jars cracking.
Pressure canningPressure canning heats sealed jars to about 116°C (240°F) under steam pressure. It is the only safe home method for low-acid foods such as vegetables.
ReheatReheating leftovers safely means heating them until steaming hot all the way through, 74°C (165°F) in the center. Here is how to do it on each appliance.
Shelf-stableShelf-stable food can be stored unopened at room temperature, like canned goods, dried pasta and UHT milk. Many of them need the fridge once opened.
Sterilize jarsSterilizing jars means heating clean glass jars to kill microbes before you fill them with jam or pickles. Boiling them for 10 minutes is the tested way.
ThawThawing brings frozen food back above freezing safely, in the fridge, in cold water or in the microwave, and never on the kitchen counter.
Use byA use by date is the safety deadline on perishable food like fresh meat, fish and dairy. After it, do not eat the food, even if it looks and smells fine.
Vacuum sealVacuum sealing removes air from a plastic bag and seals it shut. It slows freezer burn and spoilage but does not make food safe at room temperature.
Water bath canningWater bath canning preserves high-acid foods like jam, pickles and acidified tomatoes by boiling sealed jars. It is not safe for low-acid foods.