Mexican Cheese: How Long Does It Last?

The shelf life of cheese depends on its moisture content, with soft cheeses having a shorter shelf life than harder varieties. This means that Mexican soft cheeses like queso fresco, cotija, and queso blanco will have a shorter shelf life than harder Mexican cheeses like queso asadero. For example, queso fresco should be consumed within 3-5 days of purchase if it does not have preservatives, and it can last up to 2 weeks if it does. On the other hand, harder cheeses like cheddar can last 6 to 8 weeks after opening, and Parmesan can last 3 months.

Queso fresco: lasts 3-5 days without preservatives, 2 weeks with preservatives

Queso fresco, or "fresh cheese" in Spanish, is a crumbly white cheese usually made from cow's milk. It is also sometimes made with goat's milk or a combination of the two. This versatile cheese is often used as a topping for tacos, rice, enchiladas, refried beans, and quesadillas. It can also be baked and used as a dip or in a taco filling.

Queso fresco has a limited shelf life. Without preservatives, it should be used within 3-5 days of purchase. If it contains preservatives, it can last up to 2 weeks. To maximise the shelf life of queso fresco, it should be stored in a sealed, airtight container in the refrigerator. It cannot be stored at room temperature for more than two hours, as bacteria will start to grow and the cheese will spoil.

When reheating queso fresco, it is important to ensure that it reaches a temperature of at least 165°F (74°C) to guarantee safety. It can be reheated in a microwave, on the stove, or in a slow cooker.

Soft cheeses: last 1-2 weeks in the fridge

Soft cheeses, such as ricotta, feta, mozzarella, cottage cheese, and cream cheese, are highly perishable due to their high moisture content. They typically last for about 1-2 weeks in the fridge, but their quality and taste will be best before that time is up. To maximise their shelf life, soft cheeses should be stored in an airtight container, with the container placed on the top shelf or in a drawer in the fridge.

For soft cheese sold in brine, such as feta or fresh mozzarella, it is important to keep it in the liquid and ensure the container's lid is secure. For blue cheese, wrapping it in foil is recommended. Soft-ripened cheese, like Brie, has a delicate rind, so it needs more care than other soft cheeses. It is best wrapped in cheese paper, but parchment paper and an airtight container can also be used.

It is important to note that soft cheeses are more susceptible to bacterial growth and spoilage due to their high moisture content. Therefore, proper storage is crucial to maintain their quality and freshness. Additionally, soft cheeses should be consumed within a few days of purchase if they do not contain preservatives.

Hard cheeses: last 3-4 weeks in the fridge

Hard cheeses, such as aged cheddar, aged gouda, and Parmigiano Reggiano, are low in moisture, making it difficult for bacteria to flourish. This means that once opened, hard cheeses can last a long time in the fridge—approximately three to four weeks, according to experts. Unopened packages of hard cheese will last about six months, according to the USDA.

To store hard cheese in the refrigerator, follow these steps:

• Remove the cheese from its plastic packaging.
• Wrap it loosely in cheese paper or wax paper.
• Put the cheese in a container with an airtight lid.

It is important to note that hard cheeses are more prone to mould the longer they are stored, so be sure to inspect the cheese for any signs of mould before consuming. If mould is present, simply cut off at least 1 inch (2.5 cm) around and below the affected areas.

Additionally, hard cheeses can be frozen for up to six months at a safe temperature of 0°F (-18°C) or below.

Freezing cheese: can extend shelf life, but may ruin flavour and texture

Freezing cheese is a great way to extend its shelf life, but it can negatively impact the flavour and texture. Freezing is an ancient food preservation method that has been used for over 3,000 years. It's an effective way to stop food from spoiling, reduce waste, and save money.

Freezing cheese can, however, affect its texture and quality. When cheese is frozen, small ice crystals form on the inside, disrupting the internal structure of the cheese. When it’s thawed, water is released, causing the cheese to dry out, become crumbly, and potentially develop a mealy texture. Freezing can also make the cheese less meltable.

The impact of freezing varies depending on the type of cheese. Hard and semi-hard cheeses with lower moisture and higher fat contents are best suited for freezing. Delicate, hand-crafted cheeses, processed varieties, and most soft cheeses are generally unsuited to this preservation method.

Freezing cheese can also affect its flavour. The freezing process can impact the volatile compounds responsible for the cheese’s aroma and flavour. Some of these compounds may be lost or altered during freezing, leading to a less intense or nuanced flavour profile once the cheese is thawed.

Freezing cheese can be a convenient way to keep some cheeses on hand for use in cooking. However, cheese is best enjoyed fresh to maximise its flavour and texture.

Signs of spoilage: mould, drastic texture changes, fermented/yeasty/ammonia smell

Mould, drastic texture changes, and fermented/yeasty/ammonia smells are all signs that your Mexican cheese has spoiled and should not be consumed.

Mould

Mould growth on cheese can be desirable or undesirable. Some cheeses, like Stilton or Brie, are intentionally inoculated with moulds to achieve a specific flavour or texture. However, if mould grows on cheese unintentionally, it may produce spores and toxins that can make the cheese unsafe to eat. Different types of mould can cause different colours and patterns on the cheese, such as blue, red, or white spots. While some moulds on cheese are harmless, others can be toxic and potentially dangerous if consumed in large amounts. It is important to check for signs of unsafe mould growth, such as unusual colours, textures, or odours, and discard any cheese that appears spoiled or contaminated.

Drastic Texture Changes

The texture of the cheese can also indicate spoilage. Hard cheeses like Cheddar can start to crack when they spoil due to changes in moisture content and the growth of unwanted bacteria. As hard cheeses age, they lose moisture, becoming brittle and prone to cracking. To prevent cracking, store your cheese in a cool place with good air circulation and the right humidity conditions.

Soft white mould cheeses like Camembert can become slimy when they spoil due to the growth of unwanted bacteria. This can also develop an off-putting odour. If your cheese's rind is excessively gritty and slimy, it has likely gone wrong, and you should discard it.

Fermented/Yeasty/Ammonia Smell

A strong ammonia smell is one of the most common indicators of spoilage in cheese. It is produced by bacteria breaking down the protein in the cheese and has a pungent, acrid odour similar to cleaning products or urine. Excessive ammonia can indicate spoilage and may give the cheese a bitter or sour taste.

A rancid and vomit-like smell is another sign of spoilage, caused by the presence of butyric acid, a short-chain fatty acid produced by bacteria breaking down fat in the cheese. It is often associated with soft, creamy cheeses like Brie, which have a higher moisture content and are more prone to spoilage.

In general, any significant change in the smell of cheese from its normal odour can be a sign that it has gone off and should be avoided. Trust your senses, and if something seems off, it is better to err on the side of caution and discard the cheese.

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