Deconstructing the Cheesemaking Process: What Happens to the Sugar?
At its core, cheesemaking is a controlled fermentation process that involves milk, cultures, and an enzyme called rennet. Milk contains a natural sugar called lactose. The key to understanding the sugar content of cheese lies in how cheesemakers handle this lactose.
The Role of Lactic Acid Bacteria
- Acids are essential: Starter cultures, which are cocktails of bacteria, are added to milk to begin the process of acidification.
- Lactose conversion: These bacteria consume the lactose and convert it into lactic acid.
- Flavor development: This conversion not only aids in the coagulation of milk proteins into curds but also develops the characteristic flavors of the cheese during ripening or aging.
- Final product: For aged cheeses like cheddar, gouda, and parmesan, the fermentation process is so complete that there is very little to no lactose remaining in the final product.
Natural Cheese vs. Processed Cheese: A Sweet Distinction
While natural cheese production actively reduces the amount of milk sugar, the situation changes drastically with processed cheese products. Consumers need to be vigilant and read ingredient labels carefully to distinguish between the two.
Natural Cheese
Natural cheese is made directly from milk using starter cultures and rennet. The primary sugar is lactose, but as outlined above, the fermentation process eliminates most of it, especially in hard, aged varieties. Some fresher, softer natural cheeses like ricotta or mascarpone, which are not aged as long, may retain higher levels of lactose.
Processed Cheese
Processed cheese is a food product created by mixing natural cheese with other ingredients, including emulsifying agents and sometimes added sugars. These additions are used to enhance flavor, improve texture, and extend shelf life. Added sugars can include corn syrup, dextrose, or maltodextrin. Dessert-style cheeses can contain higher concentrations of sweeteners for their intended flavor profile.
How to spot the difference
To identify added sugars in processed cheese, always check the ingredient list on the packaging. Look for terms like "sugar," "corn syrup," "dextrose," or other sweeteners. Unlike natural cheese, which contains minimal carbohydrates and naturally occurring milk sugars, processed cheese often lists sugar as a distinct added ingredient.
Naturally Sweet-Flavored Cheeses: An Exception
Some cheeses are perceived as 'sweet' not because of added sugar, but due to their unique production methods or the diet of the dairy animals.
Gouda
To make Gouda, the curds are washed with warm water to remove excess lactose. This process leaves less food for the bacteria, resulting in less lactic acid production and a sweeter, more buttery-tasting cheese.
Alpine-style cheeses
Cheeses like Swiss or Fontina are made using specific cultures that consume lactose and produce propionic acid, which gives them their characteristic nutty and slightly sweet flavor. These cultures also produce carbon dioxide, creating the distinctive "eyes" or holes in the cheese.
Mascarpone
This Italian cheese is not aged and is made by warming cream and adding an acid, such as citric acid, to thicken it. Because it's not fermented by lactic acid bacteria, it retains a creamy, slightly sweet flavor from the lactose present in the cream.
Comparison Table: Sugar in Different Cheese Types
| Feature | Natural Aged Cheese (e.g., Cheddar, Parmesan) | Fresh Cheese (e.g., Cottage, Ricotta) | Processed Cheese (e.g., American Slices) |
|---|---|---|---|
| Added Sugar | No | No (except dessert preparations) | Yes, for flavor and texture |
| Lactose Content | Very low to trace amounts | Moderate, as it is not fully fermented | Can be low depending on the formulation |
| Sweetness Source | Byproducts of fermentation, lack of acid | Residual lactose from the milk | Added sweeteners like corn syrup and maltodextrin |
| Texture | Firm to hard | Soft, moist, or creamy | Smooth, uniform, and meltable |
| Primary Use | Savory applications, cheese boards | Desserts (cheesecake, cannoli), sauces | Sandwiches, melting applications |
Conclusion: Interpreting Sweetness in Cheese
In summary, the assumption that all cheese is made without added sugar is a half-truth. While traditional, natural cheesemaking relies on bacterial cultures to consume lactose, the naturally occurring sugar in milk, this is not universally true. The key difference lies in the cheese type: natural, aged cheeses contain minimal residual lactose, resulting in very low sugar content. However, consumers should be aware that many processed cheeses and dessert-style variations do contain intentionally added sugar or other sweeteners to achieve their specific flavor and texture profiles. Therefore, checking the ingredient label is the most reliable way to determine if a cheese contains added sugars beyond the natural components of milk. A classic example is the Italian dessert cheese tiramisu, which prominently features the creamy, slightly sweet mascarpone cheese.
