Water quality is crucial in cheesemaking, and choosing the right type—whether hard or soft—can impact the final product’s texture, taste, and yield. Here’s a deep dive into how hard and soft water affect cheesemaking, and why many cheesemakers carefully control mineral content in their process.
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How is water used in cheesemaking?
Water plays multiple essential roles in cheesemaking, from diluting ingredients to washing curds. Here’s a look at the main ways water is used:
1. Diluting rennet and cultures
- Rennet, the enzyme that helps coagulate milk, is often diluted in water before being added to milk. This allows for even distribution, so curds form consistently.
- Similarly, cultures, which add flavour and acidity to cheese, may also be diluted in water to make their distribution more even and ensure they blend smoothly with the milk.
2. Curd washing
- In certain cheeses, such as Gouda or Havarti, cheesemakers wash the curds with water after they’ve started forming. Adding water reduces lactose in the curd, which in turn slows acid development.
- This process produces a sweeter, milder cheese because lower lactose means less lactic acid will form during ageing.
3. Brine solution for salting
- Many cheeses are salted by soaking them in a saltwater brine. Brining helps salt penetrate the cheese, contributing to flavour, moisture control and rind formation.
- Brine baths can also act as a preservative, helping to protect the cheese from spoilage and unwanted bacterial growth.
Each use of water in cheesemaking affects the final texture, flavour and quality of the cheese. By controlling water quality and quantity, cheesemakers can ensure each batch is balanced and consistent.
What is water hardness?
Water hardness refers to the mineral content in water, specifically calcium and magnesium levels. These minerals influence several stages in cheesemaking, particularly curd formation and texture.
- Hard water: Contains high levels of calcium and magnesium. The hardness level varies by region, depending on the natural geology and water treatment processes.
- Soft water: Has lower mineral content, often due to natural conditions or water treatment that removes calcium and magnesium.
Understanding the water hardness scale
What does this all mean in actual numbers? Water hardness is typically measured in parts per million (ppm) or grains per gallon (gpg). The scale categorises water as follows:
- Soft water: 0-60 ppm or 0-3.5 gpg
- Moderately hard: 61-120 ppm or 3.6-7 gpg
- Hard: 121-180 ppm or 7.1-10.5 gpg
- Very hard: Over 180 ppm or 10.6+ gpg
By knowing your water’s hardness level, you can adjust the mineral content to optimise curd texture and quality.
How water hardness varies by region
Water hardness varies widely by region, largely due to local geology. Here are examples of areas known for either soft or hard water:
Regions with soft water
- Seattle, Washington, USA: The Pacific Northwest generally has soft water due to abundant rainfall and fewer mineral deposits in local rocks.
- Oslo, Norway: Norway’s soft water comes from surface sources with low mineral content, particularly from rivers and lakes.
- Scotland, UK: Many parts of Scotland have soft water, especially in the Highlands, where water flows through less mineral-rich granite and volcanic rock.
- Japan: Generally, Japan’s water is soft due to volcanic geology and rivers flowing through sedimentary rock.
Regions with hard water
- Las Vegas, Nevada, USA: High mineral deposits from groundwater sources lead to very hard water in the desert region.
- Midwest, USA: Many states in the Midwest, like Indiana and Wisconsin, have hard water due to high levels of limestone.
- London, UK: London’s water is hard because it comes from chalk and limestone aquifers, which add calcium and magnesium.
- Rome, Italy: Roman water is drawn from limestone-rich sources, making it particularly hard, which has been true since ancient times.
Knowing a region’s water hardness can be helpful for cheesemakers, as it provides insight into local mineral content and how it may impact curd formation.
The role of calcium in cheesemaking
Calcium is crucial for coagulation—the process that transforms milk into curd. It works with rennet, an enzyme added to milk, to firm up the curd. Without enough calcium, curds may remain too soft or fail to set properly. Conversely, excessive calcium can lead to overly firm curds that are difficult to cut and handle.
- Impact on curd structure: Calcium ions strengthen the bonds between casein molecules, creating a firmer, more cohesive curd.
- Texture and yield: A balanced calcium level not only improves texture but also maximises yield, giving cheesemakers more cheese per batch of milk.
How hard water impacts cheesemaking
- Curd formation: The additional calcium in hard water can improve curd formation, resulting in a denser curd structure. In theory, this may be useful for certain hard and semi-hard cheeses that benefit from a firmer texture, like Cheddar or Gouda. But the reality is more complex than this.
- Texture: Hard water can enhance the texture of certain cheeses, making them firmer and more resilient. However, in some cases, it can make the curd too tough, which complicates cutting and draining.
- Challenges: Hard water can occasionally create inconsistencies in the curd’s firmness. Excess calcium may also lead to “gritty” textures if the minerals don’t dissolve fully. Cheesemakers may find that cheese made with hard water can develop subtle, unintended changes in flavour due to mineral interactions.
How soft water impacts cheesemaking
- Milder curd structure: Soft water’s low mineral content results in a milder curd that is more suitable for fresh, soft cheeses, like Ricotta, Mascarpone and Mozzarella. These cheeses benefit from a more delicate texture and creaminess.
- Control over mineral content: Soft water allows cheesemakers to add calcium in a controlled way. They can introduce calcium chloride directly into the milk, ensuring just the right amount to produce a stable curd without excess minerals.
- Better for certain cheese types: Soft water may be advantageous when aiming for a creamier, softer cheese. Its minimal mineral content preserves the milk’s natural characteristics, which can enhance the cheese’s mildness and freshness.
Balancing minerals for optimal results
Many cheesemakers prefer to control mineral levels rather than relying on water quality alone. This is especially true in areas with hard water that might vary seasonally or be unpredictable in mineral content.
One common solution is to use filtered or distilled water, which provides a blank slate. Cheesemakers can then add calcium chloride to the milk as needed, achieving precise control over the mineral levels for consistent curd formation and texture.
- Calcium chloride: Often added to milk in cases where calcium is lacking, especially in pasteurised milk that has lost some of its natural minerals. By adding calcium chloride, cheesemakers ensure reliable curd formation without the risk of excess calcium from hard water.
Practical tips for cheesemakers
If you’re a cheesemaker, here are some tips for working with different types of water:
- Test water hardness: Use a water hardness test kit to understand your local water profile. If it’s extremely hard or soft, consider how that might affect your cheesemaking.
- Filter hard water: If you have hard water, consider filtering it before use. This can help control mineral content and create more predictable results.
- Adjust with calcium chloride: When using soft water, adding calcium chloride directly to the milk can support curd formation. A typical amount is around 0.02% of the milk volume, but it’s best to start with small amounts and adjust as needed.
- Experiment with different cheeses: Some cheeses thrive with a firmer curd, while others benefit from a creamier texture. Experiment to find which works best with your water source.
Best water hardness testing kits
For cheesemaking, testing water hardness helps ensure consistency in curd formation and texture. Here are some reliable water hardness testing kits that are easy to use:
1. API GH & KH Test Kit
- This kit tests both general hardness (GH) and carbonate hardness (KH). It’s often used in aquariums but works well for cheesemaking, offering precise measurements.
- Pros: Easy to use, affordable, provides accurate results for both GH and KH levels.
- Cons: Results are shown in ppm (parts per million) rather than degrees of hardness, so conversion might be needed.
2. Hach Total Hardness Test Strips
- These strips provide a quick and straightforward test for general hardness in ppm. They’re reliable and popular in food processing and water treatment.
- Pros: Fast, simple, and good for a rough idea of water hardness.
- Cons: Less precise than titration-based tests, though adequate for quick checks.
3. JNW Direct Water Hardness Test Strips
- These strips measure hardness in grains per gallon (GPG) and ppm, making them ideal for home cheesemakers looking for fast results without complex equipment.
- Pros: Affordable, quick, and includes a clear colour chart for easy reading.
- Cons: Not as precise as liquid kits, but sufficient for general use.
4. Tetra EasyStrips 6-in-1 Test Strips
- These strips are multipurpose, measuring general hardness along with other water parameters. Though designed for aquariums, they can be helpful for cheesemakers needing a quick hardness check.
- Pros: Convenient and versatile for testing various water parameters in one strip.
- Cons: May not provide the same accuracy as dedicated hardness-only kits.
Can you soften hard water?
Yes, you can transform hard water into soft water using a few common methods that remove or reduce minerals like calcium and magnesium. Here’s how:
1. Water softeners
- Traditional water softeners use an ion-exchange process, where calcium and magnesium ions are swapped with sodium or potassium ions, effectively softening the water.
- This method is highly effective but does introduce sodium, which may need to be considered for cheesemaking.
2. Reverse Osmosis (RO) systems
- RO systems use a semi-permeable membrane to filter out minerals, reducing water hardness and removing impurities.
- RO water is almost pure, making it ideal for cheesemaking, as you can add calcium chloride as needed to control curd formation.
3. Distillation
- Distillation involves boiling water to create steam, which is then condensed back into liquid, leaving minerals behind.
- Distilled water is very soft and can be used directly or with added minerals for cheesemaking purposes.
4. Chemical softening
- Adding chemicals like sodium carbonate (washing soda) can soften water by precipitating calcium and magnesium.
- This method is not ideal for drinking or cheesemaking, as it may leave residual chemicals.
For cheesemaking, RO systems or distilled water are often preferred because they allow you to control mineral content by reintroducing only the minerals necessary for curd formation, resulting in a more consistent cheese quality.
Why chlorinated water is bad for cheesemaking
On a side note, chlorinated water can also be problematic in cheesemaking because chlorine kills bacteria, including the beneficial cultures needed for proper fermentation. These cultures are essential for acidifying the milk, developing flavour, and creating the right texture. When chlorine disrupts these cultures, the result can be poor curd formation, off flavours and inconsistent batches of cheese.
Additionally, chlorine can interact with milk proteins, potentially impacting curd structure and leading to weaker curds. Cheesemakers often use filtered or dechlorinated water to avoid these issues, ensuring a healthy environment for beneficial bacteria and a reliable cheesemaking process.
Conclusion
For cheesemaking, soft (and dechlorinated) water is generally much better, as it offers a cleaner, more controlled starting point. Without excess calcium and magnesium, soft water allows cheesemakers to carefully manage curd formation by adding only the minerals they need, like calcium chloride, for optimal texture and consistency.
Using soft water can lead to smoother, more predictable results, especially in delicate cheeses, and ensures that no unwanted mineral interactions impact flavour or texture.
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!