Cheese Safety: 55 Degrees — How Long Is Too Long?

Cheese is a staple in many households and is a beloved snack at parties. But how long can it be left out of the fridge before it goes bad? The answer depends on the type of cheese and how it's made. Hard cheeses, such as cheddar and parmesan, can be left out for longer than soft cheeses like mozzarella or cream cheese. However, it's important to note that the ideal temperature for ageing cheese is between 45-58°F, and at 55°F, cheese can last almost indefinitely.

Cheese at 55 degrees is safe for a long time

Cheese at 55 degrees Fahrenheit is safe for a long time. In fact, cheese can be stored at temperatures ranging from 50 to 59 degrees Fahrenheit during the ageing process, which can last for several weeks, months, or even years. This temperature range is considered ideal for ageing cheese as it allows for the development of complex flavours and textures.

Cheese is a very resilient food item and can be left out at room temperature for a considerable amount of time without spoiling. The exact duration depends on various factors such as moisture content, acidity, salt content, and the type of cheese. Hard cheeses like Cheddar and Parmesan can be left out at room temperature for up to 8 hours, while soft cheeses like Brie and Camembert should not be left out for more than 2 to 4 hours.

At 55 degrees Fahrenheit, which is within the optimal temperature range for ageing cheese, hard cheeses can be stored safely for extended periods. This temperature allows the cheese to mature and develop its unique characteristics without spoilage. However, it is important to note that the cheese should be stored in a controlled environment, away from direct sunlight, and consumed within a reasonable timeframe.

The ageing process is crucial in cheesemaking, and higher temperatures can accelerate the development of bacteria that contribute to the cheese's flavour and texture. While 55 degrees Fahrenheit is considered safe, it is still important to monitor the cheese for any signs of spoilage, such as changes in colour, texture, or the presence of mould. Proper storage practices, such as wrapping the cheese in parchment paper or cheesecloth, can also help extend its shelf life.

In summary, cheese stored at 55 degrees Fahrenheit is generally safe for a long period, especially for hard cheeses. This temperature is within the optimal range for ageing cheese, and it allows for the development of flavour and texture without compromising food safety. However, it is important to consider the type of cheese, monitor for any signs of spoilage, and practise proper storage techniques to ensure the cheese remains safe and enjoyable.

Hard cheeses are safer than soft cheeses

Research has shown that hard cheeses like Parmesan can be left out for up to 24 hours and remain safe to eat. In contrast, soft cheeses like ricotta, queso blanco, and mascarpone will deteriorate faster when left out at room temperature. According to food safety experts, all cheeses should be discarded after being left out for more than four hours to prevent bacterial growth and spoilage. However, hard cheeses will visually appear unappealing before they make someone sick, so it is unlikely that consuming them after a prolonged period at room temperature will be dangerous.

The process of making hard and soft cheeses differs, which contributes to their varying safety profiles. To make soft cheese, curds are slowly drained over several hours, retaining moisture. The curds for hard cheeses, on the other hand, are cut into smaller pieces to release more whey, and then heated and pressed to remove even more moisture. The higher temperature and pressure used in the production of hard cheeses contribute to their lower moisture content and, consequently, their increased safety.

The aging process also affects the texture of the cheese. Some cheeses, like Brie, become softer as they age, while others, like Parmigiano Reggiano, harden over time. Sealing cheeses in wax or plastic before aging can prevent moisture evaporation, while aging without a seal allows moisture to escape, resulting in a harder cheese.

In summary, hard cheeses are generally safer than soft cheeses due to their lower moisture content, which inhibits bacterial growth. The production methods and aging processes of hard cheeses contribute to their drier texture, making them less perishable and more resilient to temperature fluctuations.

Fresh cheeses are more perishable

While cheese is generally a very resilient food, some cheeses are more perishable than others. Fresh cheeses, which are made from fresh curds that have not been pressed or aged, have the highest moisture content of all cheeses. This makes them more susceptible to bacterial growth and spoilage.

Soft, unripened cheeses such as cottage cheese, cream cheese, and Queso Fresco, as well as soft, ripened cheeses like Brie, Camembert, and fresh mozzarella, are more perishable than harder cheeses. This is because they have a higher moisture content and are not aged, which makes them more susceptible to bacteria. These cheeses should be discarded if left out at room temperature for more than two hours.

On the other hand, harder cheeses like Cheddar, Parmesan, and Gouda have a lower moisture content, which makes them less likely to have bacterial growth. They can be left out at room temperature for up to four hours and can be rewrapped and refrigerated if any signs of spoilage are absent.

The longevity of a cheese depends on its proper storage. For optimal preservation, soft and semi-soft cheeses should be stored in their natural liquid in a plastic container, while hard and semi-hard cheeses should be wrapped in butcher paper or wax paper, which allows the cheese to breathe without drying out.

Bacterial growth is unlikely at 55 degrees

The temperature range in which bacteria thrive varies depending on the bacterial species. Some bacteria, known as hyperthermophiles, have an optimal growth range of 60 degrees Celsius and above. Thermophiles, on the other hand, have an optimal growth range between 45 and 122 degrees Celsius. In contrast, mesophiles, which include many foodborne pathogenic bacteria, have an optimal growth range between 20 and 45 degrees Celsius.

Research has shown that at temperatures above 51.7 degrees Celsius (125 degrees Fahrenheit), microbial death increases progressively. This temperature falls within the range commonly referred to as the "danger zone" for food safety. However, the danger zone is not a static range, and the upper limit has changed over the years, previously being set at 45 degrees Fahrenheit (7.2 degrees Celsius) and more recently at 41 degrees Fahrenheit (5 degrees Celsius).

At 55 degrees Celsius, the growth of common foodborne pathogens, such as Bacillus cereus, is inhibited. While some strains of B. cereus can grow at this temperature in supplemented media, they are unable to do so in rice, which is a common vehicle for foodborne disease outbreaks. Additionally, studies have shown that temperatures within the upper portion of the danger zone, including 55 degrees Celsius, are lethal for vegetative cells of foodborne pathogens if the duration of exposure is sufficiently long. For example, salmonellae in egg white solids died after 7 to 10 days of exposure at temperatures from 51.7 to 54.4 degrees Celsius.

Furthermore, the rate of bacterial growth is influenced by various factors beyond temperature, including water activity, pH, salt content, oxidation-reduction potential, buffering capacity of the food, competition from other microorganisms, initial population sizes, and nutrients present in the substrate. These factors interact with temperature to determine the rate of bacterial growth or death.

Therefore, while bacterial growth may be possible at 55 degrees Celsius under certain conditions, it is generally unlikely due to the combined effects of temperature and other inhibitory factors.

Food spoilage is caused by different bacteria

Other bacteria, such as Clostridium perfringens, are also responsible for food spoilage and can cause foodborne illnesses. Spoilage bacteria are usually undetectable outside of a lab, and their waste products can be harmful. Eating deteriorated food is not considered safe due to the presence of these wastes and mycotoxins.

Food spoilage can be prevented through various methods, such as drying, salting, curing, canning, refrigeration, freezing, preservatives, irradiation, and high hydrostatic pressure. Refrigeration and freezing, in particular, are effective ways to slow down bacterial growth and maintain food quality.

Regarding cheese, it is a resilient food item and can be left at room temperature for a short period. While the ideal temperature for ageing cheese is between 45-58°F, cheese can be left at 55°F, or even slightly higher, for a few hours without spoilage. However, higher temperatures and longer durations increase the risk of bacterial growth and spoilage.

Different types of cheese also have varying resistance to spoilage. Hard, aged cheeses with low moisture content and lower pH, such as Cheddar, Parmesan, and Gouda, are less perishable and can be left out for longer. On the other hand, soft, unripened cheeses like cottage cheese and fresh soft cheeses like Queso Fresco are more perishable and should be discarded if left out for extended periods.

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