Cheese Left Out: What's The Worst That Could Happen?

Leaving cheese out for too long can be risky business. The US Department of Health recommends that perishable food should not be kept out of the fridge for more than two hours. However, the shelf life of cheese varies depending on its type, moisture content, and whether it is fresh or aged. Soft cheeses with high moisture content, such as Brie, Camembert, and cream cheese, are more perishable and susceptible to bacterial growth, and should be discarded if left out for over two hours. Harder cheeses, like Cheddar, Parmesan, and Gouda, have a lower moisture content, making them less prone to bacterial growth and able to sit out for up to four hours.

Soft cheeses like Brie and Camembert should be discarded after 2-4 hours

Soft cheeses like Brie and Camembert have a high moisture content, which means they are more perishable and susceptible to bacteria and spoilage. Therefore, they should be left out at room temperature for no longer than two hours. After this time, it's best to discard them.

The U.S. Department of Health advises that no perishable food should be left out of the fridge for more than two hours. Soft cheeses, like Brie and Camembert, are particularly susceptible to spoilage due to their high moisture content. This means they are at a higher risk of bacterial growth.

Hard cheeses, like Cheddar, Parmesan, and Gruyere, have a lower moisture content, which makes them less prone to bacterial growth. They can be left out for up to four hours and then rewrapped and put back in the fridge. However, it's important to check for signs of spoilage, such as a bad smell, a slimy surface, dark spots, dryness, cracks, or mould.

Soft cheeses, on the other hand, pose a higher risk and should be discarded if left out for longer than two hours. This is because their higher moisture content provides more opportunities for bacteria to grow, making them more perishable.

If you're unsure whether your cheese has gone bad, there are some tell-tale signs to look out for. Spoiled soft cheeses may exhibit a slimy texture, a yellowed colour, mould, sourness, or a scent of ammonia. If you see any of these signs, it's best to discard the cheese immediately.

Hard cheeses like Cheddar and Parmesan can be left out for up to 8 hours

Hard cheeses, such as Cheddar and Parmesan, can be left out for longer than soft cheeses. This is because they have a lower moisture content, which makes them less susceptible to bacterial growth. In fact, research has shown that most hard cheeses can slow the growth of bacteria, so the chance of foodborne illness caused by their consumption is extremely low.

The U.S. Department of Health advises that perishable foods should not be left out of the fridge for more than two hours. However, this timeframe is flexible when it comes to hard cheeses. If they have been left out for four hours or less, they can simply be rewrapped and put back in the fridge. After four hours, it is recommended to check for signs of spoilage, such as an unpleasant smell, a slimy surface, dark spots, dryness, cracks, or mould. If none of these signs are present, the cheese can still be safely consumed, although its quality and taste may be impacted.

Hard cheeses can be left out for up to eight hours, although this is not recommended as the quality of the cheese will likely suffer. After eight hours on a cheese board, Cheddar will probably not have a lot of bacterial growth, but it won't look appealing to eat. It is worth noting that the chance of bacterial growth increases as the cheese is left out for longer, so there is a small chance of illness, especially for those who are pregnant, elderly, or immunocompromised.

To summarise, hard cheeses like Cheddar and Parmesan can be safely left out of the fridge for up to eight hours. However, for the best quality and taste, it is recommended to limit this time to four hours or less.

The moisture content of cheese affects how long it can be left out

The moisture content of cheese does indeed affect how long it can be left out. The more moisture a cheese contains, the more quickly it will spoil. This is because moisture provides an environment that encourages bacterial growth.

Soft cheeses, such as cottage cheese, cream cheese, and mozzarella, have the highest moisture content. They are also the most perishable and should be discarded if left out for longer than two hours. Semi-soft cheeses, such as manchego, Gouda, and provolone, have a high moisture content and should be stored in their natural liquid in a plastic container.

Hard cheeses, such as Parmesan, Gruyere, and cheddar, have a lower moisture content and can be left out for longer—up to four hours. They are less likely to have bacterial growth and are, therefore, less perishable. However, it is still important to check for signs of spoilage, such as an unpleasant smell, a slimy surface, dark spots, dryness, cracks, or mold.

The length of time a cheese can be left out also depends on other factors, such as how it is made and how fresh it is. For example, cheeses that are not ripened (aged) are more perishable. Pasteurized processed cheeses, such as American cheese, are less perishable due to their blend of ingredients and heat treatment.

Cheese should be stored in the fridge in parchment paper or wax paper, not plastic wrap

Leaving cheese out at room temperature for too long can cause it to spoil and become unsafe to eat, especially if it's a soft cheese. Harder cheeses, like cheddar, can be left out for longer—up to four hours—but even these are best kept in the fridge if you want to maintain their quality and taste.

When storing cheese in the fridge, it's best to avoid plastic wrap. Cheese is a living thing, and it needs to breathe. Plastic wrap can suffocate the cheese, reducing its quality and flavour and encouraging the growth of unwanted bacteria. Plastic wrap can also cause the cheese to take on a plasticky taste.

Instead, opt for parchment paper or wax paper, which will allow the cheese to breathe and prevent additional moisture. Wrapping the cheese in parchment or wax paper and then placing it in a plastic bag or container can also help to maintain humidity. If you're feeling fancy, you can buy specialty cheese paper, which is coated in wax and polyethylene, or cheese storage bags, which are designed to keep the outside of the cheese from drying out while allowing it to breathe.

Signs of spoilage include a bad smell, slimy surface, dark spots, dryness, cracks, or mould

Soft cheeses, such as Brie, Camembert, cream cheese, cottage cheese, and mozzarella, are more perishable than hard cheeses. They have a higher moisture content, which encourages bacterial growth. Therefore, soft cheeses should be discarded if left out for longer than two hours.

Hard cheeses, such as cheddar, Parmesan, and Gouda, can be left out for longer—up to eight hours. This is because they have a lower moisture content, making them less susceptible to bacterial growth. However, hard cheeses can also spoil, and it's important to check for signs of spoilage before consuming them after a prolonged period at room temperature.

Signs of spoilage in hard cheeses include a bad smell, a slimy surface, dark spots, dryness, cracks, or mould. If you notice any of these signs, discard the cheese. If there is mould on a hard cheese, you can cut off the mouldy parts plus an extra inch and keep the rest. However, if the cheese is shredded or grated, throw away the entire bag as mould can contaminate the whole product.

While soft cheeses should be discarded after two hours at room temperature, hard cheeses can be wrapped and refrigerated if left out for up to four hours. However, it is important to check for the signs of spoilage mentioned above before consuming.

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