Does vegan mayo go bad? How long an opened jar keeps

Yes, vegan mayo goes bad. How long an opened jar keeps depends on the brand, and only 2 of the 5 makers we checked put it in writing. Follow Your Heart says Vegenaise is good until the printed date, and Chosen Foods says 2 months after opening. Past any date, smell and texture decide.

The coldest spot in your fridge is the wrong place for an opened jar. Follow Your Heart says Vegenaise stored too cold can break its emulsion and separate, and wants it on the door or anywhere away from the fan. Hellmann’s gives the same advice for its egg mayo and names the back of the fridge as the place to avoid. So pushing the jar to the coldest corner to make it last is how you end up with a split one. The tub of butter next to it has its own rules, covered in our guide to how long vegan butter lasts.

What the date on the jar actually means

According to the USDA’s Food Safety and Inspection Service (FSIS), a “Best if Used By” date tells you when a product will be at its best flavor or quality, and it is not a purchase or safety date. Except for infant formula, federal rules do not require a date on food at all. If the date passes while the food is in your home, FSIS says it should still be safe if “handled properly”, until spoilage is evident.

So the date on a jar of mayo is the maker’s promise about taste, and the part of the FSIS sentence to hold on to is the handling. A jar that spent an afternoon on a picnic table doesn’t qualify, whatever the lid says.

How long each brand says an opened jar keeps

We read what five makers publish about their egg-free mayo. Two answer the question for the jar you’re holding. For the other three, read the label on the jar you actually bought. If it gives an opened shelf life, that beats anything on this page.

Brand and product	Vegan status	Preservatives	What the maker says about an opened jar
Follow Your Heart Vegenaise	Maker says all its products are vegan	None; made without preservatives	Good until the “Best if Used by” date, opened or unopened
Chosen Foods Vegan Avocado Oil Mayo	“totally vegan”, per the maker	None on the ingredient list; rosemary extract “for freshness”	Keep in the fridge and eat within 2 months of opening
Hellmann’s Plant Based Mayo Spread & Dressing	Certified Vegan	Sorbic acid (E200) and calcium disodium EDTA (E385)	Nothing on the product page
Sir Kensington’s Vegan Mayo Classic	Egg-free, made with aquafaba	None on the ingredient list	Nothing on the product page we read
Just Mayo	Plant-based and egg-free, per the maker	Maker says no artificial preservatives; no ingredient list on its page	Nothing on the product page

Follow Your Heart Vegenaise

Follow Your Heart gives the most generous answer of the five. Vegenaise is good until the “Best if Used by” date on the side of the jar, whether it has been opened or not. It wants the jar at 36 to 41°F (about 2 to 5°C; the Celsius figures in this article are our conversions). The catch is that the whole answer rests on a date FSIS calls a quality date, so the picnic-table jar still doesn’t get the full run.

Chosen Foods Vegan Avocado Oil Mayo

Chosen Foods is stricter. Its vegan mayo, made with avocado oil and a chickpea protein blend, should go in the fridge once opened and be eaten within 2 months. The company also says its avocado oil mayo has a shelf life of up to 12 months and asks you to stick to the best-by date. It sells the vegan one in a 24 fl oz jar as well as the 12. If your household won’t get through 24 fl oz in 2 months, don’t buy the big one. The maker has already told you how that ends.

Hellmann’s Plant Based Mayo Spread & Dressing

Hellmann’s lists its plant-based jar as Certified Vegan and free from eggs, and it is the only one of the five whose published ingredients include preservatives, which the list says are “used to protect quality”. It also has no storage line on its product page. The company FAQ tells you to refrigerate its egg-based Real Mayonnaise after opening and sends vegan shoppers to the plant-based jar. Its storage guide gives opened mayo 2 to 3 months in the fridge without saying whether that covers the plant-based one, and introduces that jar with “New name, same great recipe”. On Hellmann’s own site, the jar got a new name before it got a shelf life.

If you open a jar and then forget it for a season, this is not the one to buy on the strength of a stated shelf life, because there isn’t one.

Sir Kensington’s Vegan Mayo Classic

Sir Kensington’s builds its vegan mayo on sunflower oil and organic aquafaba, the liquid chickpeas are cooked in, with no sorbic acid or EDTA on the list. The page we read is the foodservice listing for the gallon jar, and it says nothing about storage.

Just Mayo

Just’s mayo page lists egg-free and no artificial preservatives among its claims, but no ingredients and no storage advice.

Where to keep it, and how long it can sit out

In the fridge door, never the freezer. Follow Your Heart says Vegenaise should never be frozen, and Chosen Foods warns that freezing temperatures in transit can separate its jars. Freezing a jar to make it last longer just gets you a separated jar.

None of the five makers says how long its vegan jar can sit out. We use the FSIS rule for perishable food: no more than 2 hours between 40 and 140°F (about 4 and 60°C), and no more than 1 hour above 90°F (about 32°C). Hellmann’s storage guide allows mayo up to 4 hours, but it doesn’t say that applies to the plant-based jar, so we don’t borrow it. On a hot day that means an hour, then it goes back in the fridge or in the trash.

How to tell a jar has turned

FSIS’s general test is that spoiled food develops an off odor, flavor or texture. Hellmann’s describes what that looks like in mayo. Any darkening is a reason to throw it out, and a jar that has gone watery or unusually oily has a broken emulsion. Those signs were written for mayo in general. We use them for vegan jars too, because they describe what you can see rather than what went into it.

Separation is the confusing one, since the makers give it two causes. Follow Your Heart and Chosen Foods blame cold. Hellmann’s treats a broken emulsion as a jar that is no longer good. None of them says stirring it back together fixes anything, so we don’t say it either. A separated jar near or past its date goes out.

Mold is the one sign with no gray area. Hellmann’s says not to scoop it out and eat the rest. FSIS does not list mayonnaise in its mold guidance, but it says foods with high moisture content can be contaminated below the surface, and it tells you to throw out jams and jellies rather than scoop. A jar of mayo is moist all the way through, so the whole jar goes, not the top spoonful. That is our line, not an FSIS one.

Homemade vegan mayo

Nothing we read for this article gives a fridge life for homemade vegan mayo, aquafaba or otherwise. The old version of this page gave three different figures for it, none with a source behind it, so this version gives none.

Instead, we make a small batch, put it in a clean jar, get it into the fridge straight away, and hold it to the FSIS 2-hour rule while it is out. If it smells off or the texture has changed, it goes in the trash.

When you buy the next jar, pick one whose maker tells you how long it lasts once open, and check the label for egg while you’re holding it. Our roundup of the best vegan mayo shows which jars pass and which lookalikes carry egg.