Aging Cheese: How Long Before It's Too Long?

The length of time cheese is aged depends on the type of cheese and the desired flavour and texture. Fresh cheeses are often not aged at all, soft cheeses are usually aged between two weeks and two months, and hard cheeses are aged for several months or years. The ageing process is also known as ripening or maturing, and it allows time for microbes and enzymes to break down proteins and fats, influencing the texture, taste, and aroma of the cheese.

The ideal environment for ageing cheese

The optimal temperature range for ageing cheese is between 48 and 57 degrees Fahrenheit (or 9 to 14 degrees Celsius), with some sources recommending a target temperature of 52 to 55 degrees Fahrenheit. It is important to ensure that the temperature remains relatively stable, as fluctuations can impact the quality of the ageing cheese.

In terms of humidity, a high humidity level of above 90% is generally recommended. This can be achieved by using techniques such as placing a damp sponge or paper towel inside the cheese cave or using a shallow pan of water with a sterilised sponge or butter muslin. However, it is crucial to monitor the humidity levels regularly, as too much moisture can lead to mould growth and other issues.

Additionally, proper ventilation is essential to prevent the build-up of gases produced by the ageing cheese. This can be achieved by regularly opening the cheese cave or using fans to circulate the air.

By maintaining the appropriate temperature, humidity, and ventilation, cheese makers can create the ideal environment for ageing cheese and develop the desired flavours, textures, and aromas.

How to prevent cheese from drying out

To prevent cheese from drying out, it is important to control the temperature and humidity of the environment in which it is stored. This space is often referred to as a "cheese cave". The ideal temperature is between 50-55°F, and humidity levels should be maintained at 70-85%. These conditions prevent the cheese from drying out while allowing for the necessary bacterial activity that contributes to flavour development.

To achieve these conditions, you can use a wine refrigerator, which allows for precise temperature control. Set the temperature to between 55° and 65°F, and place a half-full bowl or glass of water inside to achieve the necessary 70% humidity. Alternatively, the crisper drawer of a regular refrigerator can be used for small batches. While this option is less precise, it is still manageable with careful monitoring. Place a small jar filled halfway with water in the drawer to increase humidity, and set your refrigerator to its warmest setting.

If you are using a cellar to age your cheese, the key challenge is controlling humidity. Use a plastic box with a lid to regulate humidity levels around the cheese, and store the cheese in covered plastic boxes or cabinets to protect it from environmental factors.

To elevate the humidity within a container, place a damp sponge or paper towel in the corner of the container, ensuring that it does not touch the cheese. The goal is to add moisture to the air, not to the cheese itself. The air should be damp, not wet.

If you are using boxes or containers for aging cheese, the size of the container should be around 40% cheese and 60% empty space. Do not let too much moisture build up inside the container, as this can cause condensation to drip onto the cheese. Leave the container slightly ajar to allow some moisture to escape if needed.

Regularly monitor the cheese and adjust the environment as needed. Check the cheese every other day, and if it starts to feel too dry, rub it with olive or coconut oil.

The role of humidity in the ageing process

During the ageing process, humidity needs to be removed from the cheese. This is done through equilibration, where the humidity moves from the cheese to the air. The air in the chamber is frequently replaced with warmer air from outside, which has a higher capacity to hold moisture. Therefore, the air in the chamber is saturated, and dehumidification is necessary.

The optimum humidity conditions vary depending on the type of cheese. For instance, Cheddar cheeses require low temperatures of 4 to 8°C and a relative humidity lower than 80%. In contrast, semi-hard cheeses like Tilsiter or Havarti are initially aged at a higher humidity of about 90% and then moved to a lower humidity environment of 70 to 75% during the final storage stage.

Maintaining the proper humidity during cheese ageing is crucial to achieving the desired characteristics of the final product. The humidity levels impact the decomposition of proteins, which in turn affects the consistency and taste of the cheese.

Additionally, the amount of cheese inside the ageing space, such as a cheese cave, also influences the humidity levels. As cheese ages, it naturally adds moisture to the air. Therefore, the amount of cheese in the cave will determine how much additional humidity is required to maintain the desired levels.

To regulate humidity, techniques such as using damp sponges or paper towels, shallow pans of water, or spraying the walls with sterile water are employed. The goal is to add moisture to the air without causing condensation or standing water, as this can lead to mould growth and other issues.

The importance of temperature control

Temperature control is crucial when aging cheese. The temperature of the aging space significantly influences the rate of ripening, microbial growth, and humidity. The optimal maturing temperature for most cheeses is between 10°C and 15°C (50°F and 59°F), which is generally warmer than a refrigerator but cooler than room temperature. This temperature range allows the cheese to develop its unique flavour profiles and textures. Warmer temperatures may cause the cheese to age too rapidly, and in the case of high-moisture cheeses, they might even spoil.

Colder temperatures can prevent spoilage but will dramatically slow down the aging process. Some cheeses, such as blues and bloomy rinds, benefit from a slower, colder ripening period, allowing microbes to alter the cheese without growing too quickly. Most large-scale cheddars are aged in vacuum-sealed bags at temperatures of about 35 to 40°F (1.6 to 4.4°C). Temperature changes can produce subtle differences in the resulting cheeses.

To maintain the right temperature, it is recommended to use a dedicated mini-fridge or wine cooler with adjustable temperature settings. Alternatively, a cool basement or cellar can also be used. For precise temperature regulation, investing in a temperature controller is advised. Consistency is vital, and fluctuations in temperature can negatively affect the aging process.

The temperature during the aging process also depends on the type of cheese. For example, soft-ripened cheeses like Brie and Camembert are typically aged at cooler temperatures of 6-8°C (43-46°F). In contrast, hard cheeses like Cheddar and Parmesan are aged at temperatures of 10-15°C (50-59°F).

Temperature control is a key factor in the cheesemaking process, influencing the texture, aging potential, and flavour development of the final product.

How to identify when cheese has gone bad

There is no single answer to how long cheese can be aged, as it depends on the type of cheese. Hard cheeses with low moisture content, like Parmesan, can be aged for years and years, while soft cheeses with high water content, like Chevre or Ricotta, are best eaten fresh. Soft cheeses like Camembert or Brie can be aged, but usually no longer than a month. Hard cheeses can be aged for over a decade.

Smell

Because cheese is a dairy product, one sign that it has spoiled is an "off" smell. This could be of spoiled milk, ammonia, or even of a refrigerator or freezer. A good tip is to smell the cheese when you first purchase it, so you know how it is supposed to smell and can identify any changes. However, some cheeses are naturally pungent, so smell alone may not be enough to determine if the cheese has gone bad. If a mild cheese, like Monterey Jack, smells strong like blue cheese, then it has likely gone bad.

Appearance

Cheese naturally grows mould, so if you see small amounts of surface mould, try trimming it off. If the cheese below the mould is clean and shows no other signs of spoilage, it is likely still safe to eat. However, if the entire piece is covered in thick mould, it may be best to discard it. Other appearance indicators include changes in colour, texture, sliminess, oil, or bloated packaging.

Taste

As a last resort, you may have to taste a small piece of the cheese to determine if it has gone bad. If the cheese tastes sour or has an unpleasant aftertaste, it has likely spoiled.

Frequently asked questions