Cheese Storage: How Long Can You Keep Unrefrigerated Cheese?

Cheese is a staple in many households and is a favourite at parties, but how long does it keep without refrigeration? The answer depends on the type of cheese, with hard cheeses like cheddar and parmesan lasting longer than soft cheeses like mozzarella or cream cheese. The US Department of Health recommends not keeping perishable food out of the fridge for more than two hours, and this is especially true for soft cheeses. Harder cheeses can be left out for up to four hours and will last a little longer due to their lower moisture content, which makes them less susceptible to bacterial growth.

Hard cheeses can be left out of the fridge for longer than soft cheeses

The length of time cheese can be left out of the fridge depends on its moisture content, with softer cheeses tending to spoil more quickly than harder ones. Soft cheeses, such as mozzarella, cream cheese, cottage cheese, brie, and fresh ricotta, have a high moisture content, making them more perishable and susceptible to bacterial growth than harder cheeses. The U.S. Department of Health recommends that perishable foods, including soft cheeses, are not left out of the fridge for more than two hours.

Hard cheeses, on the other hand, like cheddar, Parmesan, and Gouda, have a lower moisture content, which makes them less susceptible to bacterial growth and able to be left out of the fridge for longer. If they have been sitting out for four hours or less, they can be rewrapped and put back in the fridge. Harder cheeses are also less likely to pose a health risk if left out of the fridge for longer than soft cheeses, although their quality and taste may be impacted.

The aging process also plays a role in how long a cheese can be left out of the fridge. Hard cheeses are aged for longer periods of time, during which much of the moisture is removed. They are then either brined to create a hard rind or waxed and aged for between two and 36 months, or even longer. This aging process results in a lower moisture content, which contributes to their longer shelf life out of the fridge.

In addition to moisture content and aging, other factors such as the cheese-making process, freshness, and storage method can also affect how long a cheese can be left out of the fridge. For example, cheeses stored in brine or oil, such as feta, can last for a long time at room temperature. Proper storage, such as wrapping hard cheeses in breathable materials like wax or parchment paper, can also help extend their shelf life outside of the fridge.

Soft cheeses should be discarded after two hours at room temperature

Soft cheeses, also known as fresh cheeses, are more delicate and creamy, and are made from fresh curds that have not been pressed or aged. Examples include cottage cheese, cream cheese, mozzarella, burrata, and feta. These cheeses have a high moisture content, ranging from grainy textures to smooth and spreadable consistencies.

Due to their high moisture content, soft cheeses are more perishable and should not be left out at room temperature for extended periods. The U.S. Department of Health recommends discarding perishable foods, including soft cheeses, if they have been left out of the refrigerator for more than two hours.

Leaving soft cheeses unrefrigerated for longer than two hours increases the risk of bacterial growth and spoilage. This can lead to food safety issues and potential health risks. Therefore, it is essential to follow the two-hour guideline for soft cheeses to prevent foodborne illnesses.

Additionally, the quality and taste of soft cheeses can be impacted if left out for longer than two hours. They may become dry, develop cracks, or form mould. To maintain the freshness and safety of soft cheeses, it is best to store them in the refrigerator and consume them within the recommended time frame.

Hard cheeses are less likely to encourage bacterial growth

The process of making hard cheese also contributes to its longevity. During the cheesemaking process, most of the whey is removed from the curds, which further reduces the moisture content. The cheese is then either brined or waxed and aged for an extended period, typically between two and 36 months. This aging process not only develops complex flavours but also helps to preserve the cheese.

Additionally, hard cheeses often have a lower pH, making them more acidic. The higher acidity also inhibits bacterial growth. Cheeses like Cheddar, Parmesan, and Gouda fall into this category. These cheeses are made from pasteurized milk and have a lower moisture content, making them less perishable.

It is important to note that while hard cheeses can be left out of the fridge for longer periods, they should still be stored properly to maintain their quality. They should be wrapped in a breathable material like parchment paper or cheesecloth and stored in a cool, dry place.

In summary, hard cheeses are less likely to encourage bacterial growth due to their lower moisture content, longer aging process, and higher acidity. When stored properly, they can be left out of the fridge for extended periods without posing a health risk or significant changes in taste and quality.

The more acidic the cheese, the safer it is to be stored at higher temperatures

The length of time cheese can be kept without refrigeration depends on several factors, including the type of cheese, moisture content, salt content, and acidity. Generally, harder cheeses with lower moisture content, such as Cheddar, Parmesan, or Gouda, can be left out of the fridge for longer than softer, higher-moisture cheeses like mozzarella or cream cheese.

Among the different types of cheese, the more acidic the cheese, the safer it is to be stored at higher temperatures. For example, feta cheese, which has a similar acidity to yogurt, can be stored at room temperature if it is sitting in brine at the correct acidity. Other very acidic cheeses include cheddar and mozzarella, which have a pH of around 5.3. Havarti, with a pH of about 5.5, is slightly less acidic. These rindless cheeses are more susceptible to mold growth, which can transport bacteria to the inside of the cheese. However, if these harder cheeses are salted appropriately (2% salt by weight) and have a reasonable pH (5.5 or below), the risk of spoilage is still fairly low.

On the other hand, "rind-ripened" cheeses like Muenster and Brie have higher pH levels (above 6) and are more susceptible to spoilage. These cheeses tend to have softer centers due to reduced acidity. While the rind acts as a protective barrier, once the cheese is cut or the rind is broken, it should be consumed within a week or so, even if stored in the fridge.

In summary, the acidity level of cheese plays a crucial role in determining its shelf life outside of refrigeration. The more acidic cheeses, such as feta, cheddar, and mozzarella, can be stored at higher temperatures for longer periods, while less acidic "rind-ripened" cheeses like Muenster and Brie are more susceptible to spoilage and should be consumed more quickly.

Leaving cheese out of the fridge may impact its quality and taste

Soft cheeses with high moisture content, such as cottage cheese, cream cheese, and fresh mozzarella, are more perishable and should not be left unrefrigerated for more than two hours. These types of cheeses are more susceptible to bacterial growth and spoilage due to their higher moisture content. Leaving soft cheeses out for longer periods can affect their quality, taste, and safety.

On the other hand, hard cheeses like cheddar, Parmesan, and Swiss cheese have a lower moisture content, which makes them less prone to bacterial growth. They can be left out of the fridge for up to four hours, but it is still important to check for signs of spoilage before consuming them. Harder cheeses may also experience changes in quality and taste if left unrefrigerated for extended periods.

The acidity and salt content of cheese also play a role in its perishability. More acidic and well-salted cheeses can inhibit the growth of harmful bacteria and prolong their shelf life at room temperature. Additionally, the presence of a rind on aged cheeses acts as a barrier against unwanted microorganisms.

Overall, while leaving cheese out of the fridge may not always pose immediate health risks, it can definitely impact its quality and taste over time. To maintain optimal flavour and safety, it is generally recommended to keep perishable cheeses refrigerated and to let them come to room temperature for about 20-30 minutes before serving.

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