Why Cheesemakers Use Citric Acid To Make Cheese

Citric acid is a popular ingredient in cheesemaking, especially for quick, unaged cheeses like Mozzarella and Paneer. It provides a simple and reliable way to acidify milk, ensuring consistent results. But what exactly is citric acid, how does it work, and is it safe to eat? This post explores the science behind citric acid, its applications in making cheese, and provides step-by-step guides for using it.

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What is citric acid?

Citric acid is an organic compound found naturally in citrus fruits such as lemons and limes. It is a weak acid with a sour taste and is widely used as a preservative and flavour enhancer in the food industry. Most food-grade citric acid is produced industrially through fermentation. It is sold as a fine, white powder that dissolves easily in water, making it ideal for culinary and cheesemaking purposes.

Role of citric acid in cheesemaking

Acidification is an essential step in cheesemaking. It lowers the pH of milk, causing the proteins to coagulate and form curds. Citric acid simplifies this process by providing immediate acidification, unlike bacterial cultures, which take hours to produce lactic acid. This makes citric acid especially useful for making fresh cheeses that do not require fermentation.

The science behind citric acid

Milk contains casein proteins suspended in a liquid called whey. These proteins remain stable at neutral pH but start to clump together as acidity increases. When citric acid lowers the pH to around 4.6, the casein proteins coagulate, forming curds. This process, called isoelectric precipitation, is key to cheesemaking.

Citric acid also affects calcium ions in milk. It chelates (binds) calcium, softening the curds and making them pliable. This property is essential for cheeses like Mozzarella, where stretchability is a hallmark.

Is citric acid safe to eat?

Citric acid is safe to consume in the amounts used for cheesemaking. It is recognised as safe by regulatory bodies like the European Food Safety Authority (EFSA) and the US Food and Drug Administration (FDA).

• Naturally occurring: Citric acid is found in many fruits and is a natural part of a balanced diet.
• Common food additive: It is used in soft drinks, candies, sauces and more as a preservative and flavour enhancer.
• Moderation is key: Cheesemaking uses only small amounts of citric acid, posing no health risks to most people.

However, excessive consumption of citric acid in processed foods can irritate the stomach or damage tooth enamel. Those sensitive to mould by-products (used in industrial citric acid production) should check product labels.

Advantages of using citric acid in cheesemaking

• Speed: It eliminates the need for slow fermentation, making the process faster.
• Precision: Citric acid allows for precise pH control, ensuring consistent results.
• Simplicity: It simplifies cheesemaking, especially for beginners and home cooks.
• Safety: Reduces the risk of contamination compared to using bacterial cultures.

Drawbacks of citric acid in cheesemaking

While citric acid offers many benefits, it is unsuitable for all cheeses. Traditional aged cheeses, like Cheddar or Brie, rely on bacterial cultures for complex flavour development. Citric acid cannot replicate the nuanced taste profiles that fermentation provides.

Case study 1: Making Mozzarella with citric acid

Making Mozzarella with citric acid is a quick and rewarding process. This method eliminates the need for bacterial cultures, providing a fast and reliable way to enjoy fresh, stretchy cheese. Citric acid helps lower the milk’s pH, enabling the formation of curds and enhancing the elasticity of the final product.

Follow this step-by-step guide to create your own homemade Mozzarella in under an hour:

1. Dissolve citric acid: Dissolve 1 ½ teaspoons of citric acid in 1 cup of cool, chlorine-free water. Stir until dissolved.
2. Heat the milk: Pour 4 litres (1 gallon) of whole milk into a pot and heat to 32°C (90°F).
3. Add citric acid: Stir the solution into the milk. Mix gently for even distribution.
4. Add rennet (optional): Dissolve ¼ teaspoon of liquid rennet in ¼ cup of water and stir it into the milk.
5. Curd formation: Heat the milk to 37°C (98°F). Curds will form and separate from the whey.
6. Cut the curds: Cut the curds into 1-inch cubes and let them rest for 5 minutes.
7. Heat the curds: Gently heat the curds to 42°C (108°F) while stirring to release more whey.
8. Drain the curds: Pour the mixture into a colander to separate curds from whey.
9. Stretch the curds: Heat the curds in a microwave for 30 seconds and knead them until they become elastic.
10. Shape the cheese: Shape the Mozzarella into balls and chill in ice water.

Case study 2: Making Paneer with citric acid

Paneer, a versatile and mild Indian cheese, is incredibly easy to make at home using citric acid. This method ensures clean curd separation and yields a soft, creamy cheese perfect for cooking or eating fresh. Citric acid simplifies the process, making it ideal for beginners.

Follow these steps to make delicious Paneer with minimal effort:

1. Dissolve citric acid: Dissolve 1 teaspoon of citric acid in 1 cup of warm water. Stir until fully dissolved.
2. Heat the milk: Pour 2 litres (½ gallon) of whole milk into a pot. Heat slowly to 85°C (185°F).
3. Add citric acid: Remove from heat and stir in the citric acid solution. Milk will curdle, forming curds and whey.
4. Rest the curds: Let the curds sit undisturbed for 5 minutes.
5. Drain the curds: Pour the curds into a cheesecloth-lined colander to separate them from the whey.
6. Rinse the curds: Rinse the curds under cool water to remove excess citric acid.
7. Press the Paneer: Gather the cheesecloth into a bundle, twist, and press under a heavy weight for 30–60 minutes.
8. Shape and store: Unwrap the Paneer and cut it into cubes. Store or use immediately.

Conclusion

Citric acid is a powerful tool for cheesemakers. It simplifies the process, offers precise control, and speeds up curd formation. While it is ideal for fresh cheeses like Mozzarella and Paneer, it cannot replace the complex flavours of cultured cheeses. Its safety, versatility, and ease of use make it a favourite among beginners and professionals alike. With citric acid, cheesemaking at home becomes an accessible and rewarding experience.

Jonah Kincaid

Jonah is a a hipster, eco-warrior and slow food afficionado. Coming from a scientific background, Jonah has a particular interest in cheese science. And yes, he loves a good cheese pun!