You forgot to put the half and half back in the fridge after your morning coffee. It has been sitting on the counter for a few hours now. Or maybe you picked up a box of individual creamers at the store and are wondering if they need a place in the fridge. Either way, the question is the same: should half and half be refrigerated?
Should the half and half be refrigerated?
Short answer: Yes, the box of half and half should always be in the fridge, even unopened. The only exception is individual UHT creams (small single serve cups), which are shelf stable and do not need to be refrigerated until opened. Cardboard left outside for more than 2 hours at room temperature must be thrown away.
For full details of dairy storage rules, visit Food storage guide.
To take the keys
- Carton half and half: always in the refrigerator, even if ultra-pasteurized and unopened
- Store at 40 degrees Fahrenheit or below
- Leave out more than 2 hours: discard
- Individual UHT cream containers (cups): shelf stable, no need to chill before opening
- Do not store in the refrigerator door; the main shelf maintains a more consistent temperature
Should half and half cartons be refrigerated?
Yes, without exception. Half and half sold in cartons is a perishable dairy product and should be refrigerated at all times. This applies whether the carton has been opened and whether the label says “ultra-pasteurized” or standard pasteurized.
Organic Valley states it directly in their ultra-pasteurized half and half: “Half and half is a perishable item and must be refrigerated. Do not leave unrefrigerated for extended periods of time.” The USDA recommends keeping the refrigerator at or below 40 degrees Fahrenheit for all perishable dairy products.
A common point of confusion is the term “ultra-pasteurized.” Many people think this means that the product does not need refrigeration, as if it is shelf stable. It is not Ultra-pasteurization kills more bacteria and extends the unopened refrigerated shelf life to 30 to 90 days. But the carton is not filled in completely aseptic conditions, so it needs to be constantly cooled. After opening the ultra-pasteurized carton, the same 7 to 10 day window applies as with any other half and half.
Ultra-pasteurized does not mean shelf-stableThere is an important distinction between ultra-pasteurized (UP) and ultra-high temperature (UHT) packaged in aseptic containers. Half-and-half cartons in US grocery stores are ultra-pasteurized, meaning they were heated to at least 280 degrees Fahrenheit. This process kills more bacteria than standard pasteurization and gives the product a longer shelf life. But “chilled” is the key word. The cardboard must be cold.
UHT half and half in aseptic containers (sealed like a juice box) is another product. This version can be kept for months without refrigeration. This is the individual dinner creamer. Standard carton, even if labeled ultra-pasteurized, is not this product and should be refrigerated.
What about individual half and half creams?
The little plastic half and half cups you get at diners, hotels, and coffee shops don’t need refrigeration. They are processed by UHT and sealed under aseptic conditions so that they are stable for 6 months or more. They also have stabilizers that are half and half of regular cardboard. Once you open one, use it right away.
If you bought a box of individual creams that came from the refrigerated section of the grocery store, check the label. Some brands pack cream containers that need to be refrigerated. The label will tell you. In general, if it sold cold, keep it cold.
How to store half and half properly
Good storage practices
- Temperature: Keep the refrigerator at or below 40 degrees Fahrenheit (4 degrees Celsius).
- Place: Store in the main body of the refrigerator, not in the door. Every time the refrigerator is opened, the door temperatures change.
- Keep it closed: Close the carton tightly after use to limit exposure to air and to prevent the half from absorbing refrigerator odors.
- Track opening date: The date printed on the carton is less important than how long it has been open. Write the start date on the card if you forget.
- More than 2 hours left: Discard Do not return to the refrigerator and use later.
What if I accidentally left half and half out?
The USDA recommends discarding perishable food left at room temperature for more than 2 hours. On a hot day above 90 degrees Fahrenheit, that window shrinks to an hour. This applies to both an opened and an unopened carton.
If your half and half has been sitting for less than 2 hours and it’s still cool to the touch, it’s likely to go back to the fridge. If it has been outside for a long time, or if it is warm, the safest way is to throw it outside. Bacteria can multiply rapidly in temperatures between 40 and 140 degrees Fahrenheit, and you can’t tell a bacterial load from smell or appearance alone.
Can you freeze half and half instead of refrigerating it?
Freezing significantly extends the life of half and half, but it comes with a trade-off. Fat and liquid components separate during freezing. Thawed half-and-half tends to be lumpy and uneven. Stirring helps re-incorporate the mixture, but the texture isn’t fully restored.
Frozen half and half are used in cooked applications, such as soups, sauces, and baking, rather than as coffee creamer. Land O’Lakes does not recommend freezing half and half and does not guarantee quality after thawing. If you have a carton that you won’t finish before it goes bad, freezing can reduce scraps for cooked applications, but be aware that the texture will be different. Properly frozen half and half keeps for 3 months.
Recipes that use half and half
Are you working through a cardboard box before you turn it on? Half and half adds richness to soups, pasta sauces and baked goods. Use this dark hot chocolatetry this classic meat quick and easyor add a splash to mashed potatoes or scrambled eggs for a richer result.
Frequently Asked Questions: Can you leave ultra-pasteurized half and half unrefrigerated?no Ultra-pasteurized half-and-half cartons require continuous refrigeration. Ultra-pasteurization kills more bacteria and extends unopened refrigerated shelf life, but does not stabilize the product on shelves. The half and the only half that does not require refrigeration before opening are individual UHT creams in aseptic containers, which are a completely different product.
FAQ: Should half and half be stored in the refrigerator door?no The refrigerator door experiences a greater temperature variation than the main body of the refrigerator. Every time the door is opened, the cold air escapes and the door compartments warm up a little. For a product as temperature-sensitive as half and half, a spot on an interior shelf toward the back of the refrigerator is a better option. The same advice applies to other dairy products the butter and heavy cream.
FAQ: How long do half and half last after opening?An open carton of half and half lasts 7 to 10 days in the refrigerator. Organic Valley recommends 5 days for the best quality in their ultra-pasteurized variety. The date printed on the carton is less important after opening. It’s important to keep track of when you’ve opened it and keep it cold at all times. For more details on durability and signs of deterioration, see half and half goes bad.
Further reading
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