Are you storing your condiments correctly?

When we quizzed people on how they store their sauces, we discovered a lot of confusion, misinformation and downright bad habits – including ones that could be putting your health at risk.

By law, manufacturers are required to put storage guidance on their products. But more than a third of people we asked in a 2020 poll said they never check to see where condiments should be stored, or for how long.*

We consulted food experts, including a registered dietitian, for the definitive guide to what goes where and why.

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What sauce goes where?

Condiments and sauces you should keep in the fridge

Mayonnaise

What the label advises: After opening, keep refrigerated and use within three months (Hellmann's Real Mayonnaise).

What the experts say: Although it contains vinegar, there's not enough in there to safely store this creamy, egg-rich condiment outside the fridge.

Dietitian Dr Sarah Schenker says: 'Pasteurisation provides an extra layer of safety, but it should still be refrigerated.'

Refrigerating mayonnaise will limit the growth of bacteria that you might have introduced by dipping cutlery into the jar.

Pesto

What the label advises: Keep in the fridge for two weeks after opening (Sacla Classic Basil Pesto).

What the experts say: Pesto should definitely be refrigerated.

Nuts in pesto mean it can end up developing mould that produces toxic compounds called mycotoxins – this includes aflatoxin, a dangerous bacteria that can cause serious liver damage.

The trouble is, you can't see these toxins, so you won't even know if they're there – or if you've eaten them.

Dr Schenker says: 'Mould can be hard to see on pesto, especially if it's green, so don't take any chances either way, and stick to the label advice.'

• Find out more: the unexpected ingredients in your shop-bought pesto

Salad cream

What the label advises: After opening, refrigerate and eat within eight weeks (Heinz Salad Cream).

What the experts say: Although salad cream typically contains the preservative potassium sorbate, as well as spirit vinegar, it also contains egg.

Therefore, like mayonnaise and tartare sauce, it should be refrigerated.

Dr Schenker says: 'Condiments like salad cream are often left lingering outside during summer parties and barbecues. It's best to decant some into a bowl to use, to prevent the entire bottle lying around in warm conditions.'

Maple syrup

What the label advises: Refrigerate after opening and use within four weeks (Buckwud Organic Canadian Maple Syrup).

What the experts say: In anything with a sugar content of more than 60%, the sugar acts as a preservative to keep microbial degradation at bay.

Maple syrup falls just short of this, allowing some moulds to take hold, so store it in the fridge.

If you keep it in a cupboard, you may find mould forming, especially on the lid because of its exposure to air when you open it.

Dr Schenker says: 'People may think that because it's a syrup, it can be treated like others syrups such as golden syrup. But they're from different plants and have different properties, so require different treatment.'

Tartare sauce

What the label advises: Refrigerate after opening and use within two months (Colman's Tartare Sauce).

What the experts say: Tartare sauce contains egg, so this is definitely one to keep in the fridge.

It also has low acidity and a high water content, which microorganisms love.

Dr Schenker says: 'Remember to check opened jars of so-called "occasion" sauces, such as tartare sauce or cranberry sauce, before you eat them, because it may be some time since you last had the need to use them.'

Redcurrant jelly

What the label advises: Once opened, refrigerate and consume within four weeks (Baxters Redcurrant Jelly).

What the experts say: This is best stored in the fridge once opened.

Dr Schenker says: 'There can be a separation of water on the surface that creates a layer with low sugar content, which is an ideal breeding ground for mould.'

Best cheap supermarket food and drink – discover the own-brands that bested the big brands in our taste tests

Condiments you can keep in the cupboard

Ketchup

What the label advises: Refrigerate once open and eat within eight weeks (Heinz Tomato Ketchup).

What the experts say: It's not essential to keep ketchup in the fridge.

Not only does it contain vinegar, but tomatoes are naturally acidic, and this helps to preserve the product in ambient (room temperature) conditions.

Dr Schenker says: 'Sometimes people keep ketchup in the fridge, simply because they prefer a chilled taste, but otherwise it doesn't need to be refrigerated.'

This can be a hotly contested one, but ultimately it depends on your preference, home environment (if your kitchen tends to be cool or really hot, for example) and how much space you have. 

In 2017, Heinz issued a statement saying: 'Because of its natural acidity, Heinz Ketchup is shelf-stable. However, its stability after opening can be affected by storage conditions. We recommend that this product, like any processed food, be refrigerated after opening. Refrigeration will maintain the best product quality after opening.' 

Brown sauce

What the label advises: No guidance about refrigeration, just 'Best before: see cap' (HP Sauce).

What the experts say: HP Sauce contains preservative ingredients including both malt vinegar and spirit vinegar, so it's fine to keep in the cupboard, along with your ketchup.

Dr Schenker says: 'It's vinegar-based, so keeping it in the fridge isn't necessary.'

Honey

What the label advises: Store at room temperature (Rowse Squeezy Clear Honey).

What the experts say: Honey naturally contains the preservative hydrogen peroxide.

Not only that, but a high sugar content forces water out by osmosis, creating an inhospitable environment for microorganisms – even at room temperature.

Dr Schenker says: 'Honey is found in hives at an ambient temperature - much like keeping it in a cupboard – so refrigeration isn't necessary.'

Mint sauce

What the label advises: Refrigerate after opening and use within four weeks (Colman's Mint Sauce).

What the experts say: After mint, the second most abundant ingredient in this is spirit vinegar.

This acts as a preservative, so it's not essential to keep it in the fridge.

Dr Schenker, however, does warn this is another one to be careful of because it's an 'occasion sauce' that might languish in your cupboards for years. She says: 'The trouble with "occasion" sauces is that they can sit around for a long time between uses. That's why it's best to refrigerate them and throw them out if you can't recall when you opened them.'

It goes without saying that if it looks or smells iffy, or has any sign of mould, you should discard it. It's another one that's worth decanting for the table too, to avoid people dipping in and out with different cutlery.

Pickle

What the label advises: Once opened, keep in the fridge and use within six weeks (Branston Original Pickle).

What the experts say: This is fine to keep in the cupboard, as it contains preservatives including vinegar.

The main problem with pickles is that stray crumbs of bread, or morsels of food such as cheese, can be introduced when you stick a knife in – so make sure you use a clean one.

Dr Schenker says: 'Pickles and chutneys originally came about as a way of preserving fresh fruit and vegetables so, by their very nature, they're OK outside the fridge.'

Olive oil

What the label advises: Store at room temperature, away from heat and direct sunlight (Filippo Berio Extra Virgin Olive Oil).

What the experts say: Storing olive oil in the fridge will cause it to solidify, so keep it in a cupboard instead.

Dr Schenker says: 'This is just a pure ingredient, so there is nothing that can contaminate it, such as bacteria. Therefore it's fine at an ambient temperature.'

See which products impressed the experts in our extra virgin olive oil taste test.

Soy sauce

What the label advises: Refrigerate after opening (Kikkoman Soy Sauce).

What the experts say: Refrigeration is only required if you're concerned about keeping the quality and flavour at their peak for longer.

Dr Schenker says: 'There's no need to refrigerate soy sauce, because anything with such a high salt content is highly preserved.'

Mango chutney

What the label advises: Once opened, keep refrigerated and use within six weeks (Sharwood's Green Label Mango Chutney).

What the experts say: Acetic acid and a high sugar content act as preservatives to keep microbial degradation at bay, so mango chutney doesn't need refrigeration.

Dr Schenker says: 'Much like pickle, mango chutney has also gone through a process of being preserved, so it doesn't need to be in the fridge.'

Malt vinegar

What the label advises: Ensure the lid is closed and store in a cool, dry place out of direct sunlight (Sarsons Malt Vinegar).

What the experts say: Vinegar has an indefinite shelf life at room temperature, and can therefore be safely kept in a cupboard for years.

Dr Schenker says: 'The high acidity of vinegar means that any contaminant such as bacteria or mould getting into the bottle wouldn't stand a chance of living.'

Hot pepper sauce

What the label advises: Keep refrigerated and use within three months (Nando's Peri-Peri Sauce Medium).

What the experts say: This contains vinegar as one of the main ingredients, which helps to preserve it.

Although the suggestion is to keep it refrigerated, it can be safely kept in a cupboard in ambient conditions.

Dr Schenker says: 'Some chilli sauces also contain high amounts of sugar, which give extra preservative protection.'

Worcestershire sauce

What the label advises: Best before end: see cap (Lea & Perrins Worcestershire Sauce).

What the experts say: Some people think that because it contains fish, it has to be refrigerated once opened.

However, because it's already a fermented product, it won't go off and it's fine to store it in a cupboard.

Dr Schenker says: 'Fermented foods can last for ages because, technically, they've already “gone off”. However, like wine, they will eventually oxidise, especially as you get towards the end of the bottle and more air gets in.'

Oxidation is when a food starts reacting to oxygen – like cut apples going brown – and the process can affect such things as flavour or appearance, including colour.

English mustard

What the label advises: After opening, keep refrigerated and use within three months (Colman's Original English Mustard).

What the experts say: Feel free to either refrigerate or keep this vinegar-rich condiment in a cupboard – it's more a matter of preference.

Dr Schenker says: 'Storing mustard in the fridge is more about preserving the colour, which may change in a warmer environment.'

Dijon mustard

What the label advises: After opening, keep refrigerated and use within one month (Maille Dijon Original Mustard).

What the experts say: Made with wine, this French mustard also contains the preservatives potassium metabisulphite and citric acid.

Dr Schenker says: 'These preservatives mean it's fine to keep it in a cupboard, although keeping it in the fridge may help to preserve its kick and punchiness for longer.'

Wholegrain mustard

What the label advises: After opening, keep refrigerated and use within three months (Maille Wholegrain Mustard).

What the experts say: Like Dijon mustard, this can be kept in the cupboard, thanks to preservatives including vinegar and lactic acid.

Dr Schenker does warn though: 'Be extra vigilant about not contaminating the product with bits of other food, as the texture could make it hard to see whether mould is developing.'

Piccalilli

What the label advises: Once opened, keep refrigerated and consume within six weeks (Haywards Piccalilli).

What the experts say: This pickle contains enough vinegar, as well as preservative potassium sorbate, to be kept in ambient conditions after opening.

However, storing it in the fridge may help to keep the colour true, so either solution is fine.

Dr Schenker says: 'Keeping it in the fridge might also help to keep the vegetables in it crispy, but that's down to preference.'

How to store sauces safely

Do

• understand that 'use-by' dates are about safety, while 'best-before' relates to quality. An easy way to remember it is, 'Use-by; say goodbye. Best-before; eat some more.'
• what the Food Standards Agency advises. Use common sense and sensory cues such as smell and taste to determine whether a food can be eaten beyond its 'best-before' date. However, 'use-by' dates should be strictly adhered to – no guesswork.
• remember we typically live in warmer homes than in the past. Homes are generally warmer by four degrees Celsius than they were in 1970, so bear this in mind if you're still making decisions about where to store food – fridge or cupboard – based on what you've always done.
• choose 'top down' bottles with silicone valves where possible. These will help to keep products fresher for longer by keeping air out and dispensing with mucky bottle tops.

Don't

• keep olive oil in clear bottles out on worktops. This is especially important if it's a sunny room. Instead, keep it in a cupboard or choose green-bottled brands, which will be more resistant to light degradation. Keep away from heat too.
• worry about a little bit of mould on products such as jams, jellies and fruit sauces. Experts say if you're in good health, scrape it off and eat what's underneath. Avoid breathing in spores, and discard if the food tastes 'fizzy' and you're prone to an unsettled stomach.
• risk cross-contamination. Putting your toast knife into the honey or dipping a sausage in the mayonnaise could introduce morsels of perishable foodstuffs that could shorten their shelf life, so use clean cutlery if you're dipping into a jar.

Story originally published February 2020, but checked and updated for October 2024. Poll results based on a Which? Twitter poll of 444 respondents, January 2020, which asked 'Do you ever look at the label of condiments to check where they should be stored and for how long?'.