Is there any sugar in mozzarella cheese? The truth about dairy carbs

December 19, 2025 •

3 min read

Most mozzarella cheese contains only trace amounts of sugar, with some varieties reporting as low as 0 grams per serving. The misconception about sugar in mozzarella cheese stems from milk's natural lactose content, but the cheesemaking process largely eliminates this sugar.

Quick Summary

The vast majority of milk's natural lactose is removed or fermented during cheesemaking, resulting in mozzarella with very little to no sugar. This makes it an ideal option for low-carb diets, although the exact amount can vary by type.

Key Points

Minimal Sugar: Mozzarella cheese contains only trace amounts of sugar, typically less than 1 gram per ounce, with some types reporting 0g.
Lactose is Converted: The sugar that does exist in milk, lactose, is converted to lactic acid by bacteria during the cheesemaking process.
Whey Removal is Key: The majority of lactose is washed away with the liquid whey when the cheese curds are formed and drained.
Different Types Vary: Fresh mozzarella has slightly more residual lactose (2-3g per 100g) than low-moisture varieties, but both are low-sugar.
Low-Carb Friendly: Due to its low carbohydrate and sugar count, mozzarella is an excellent option for those on a keto or other low-carb diet.
Check Labels: Nutrition labels can confirm the specific sugar content, which may differ slightly between whole milk and part-skim versions.

The Mozzarella-Making Process: Where Does the Sugar Go?

Milk, the primary ingredient for cheese, naturally contains a sugar called lactose. However, the process of making mozzarella is key to why the final product contains minimal sugar. Cheese production involves several steps that systematically reduce the lactose content:

Curdling and Separation: The process begins with adding a starter culture of lactic acid bacteria and an enzyme (rennet) to milk. The bacteria ferment the lactose, converting it into lactic acid. The enzymes cause the milk to separate into solid curds and liquid whey.
Whey Drainage: Most of the lactose is water-soluble and is drained away with the whey. This single step removes approximately 90% of the original lactose from the milk.
Fermentation and Aging: The lactic acid bacteria continue to metabolize any remaining lactose in the cheese curds, further reducing its quantity. While mozzarella is not a long-aged cheese, this fermentation contributes to its low sugar content.
Heating and Stretching (Pasta Filata): In the unique 'pasta filata' method for fresh mozzarella, the curds are heated and stretched. This step forces out even more whey, effectively reducing the lactose even further and contributing to the cheese's signature texture.

Why Aged Cheeses Have Less Lactose

The longer a cheese is aged, the longer the bacteria have to consume the lactose, leading to an even lower sugar content. Fresh mozzarella, having a shorter production time and higher moisture, contains slightly more lactose than hard, aged varieties like Parmesan.

How Much Sugar is in Your Mozzarella?

The sugar content in mozzarella can vary depending on whether it's fresh, low-moisture, whole milk, or part-skim. All varieties are considered very low-sugar, making them suitable for most diets.

Here are some typical sugar values based on nutrition data:

Whole Milk Mozzarella (1 oz): Reports show around 0.29g of sugar.
Part-Skim Low-Moisture Mozzarella (1 oz): This variety often has even less sugar, around 0.17g.
Fresh Mozzarella (100g): This can contain slightly more lactose, with some sources listing around 2.5g.

Comparing Mozzarella Sugar Content

To put mozzarella's sugar content in perspective, here is a comparison with other common cheeses:


Cheese Type	Lactose/Sugar (g per 100g)	Notes
Mozzarella (Fresh)	1-3g	Lower due to whey reduction and fermentation.
Cottage Cheese	2.5-4.1g	Higher moisture content retains more whey.
Cream Cheese	~3.5g	Retains more whey than mozzarella.
Cheddar (Aged)	<0.1g	Aged longer, allowing more time for lactose to break down.
Parmesan (Hard)	<0.1g	Very low lactose due to extensive aging.

Mozzarella and Low-Carb Diets

Thanks to its minimal carbohydrate and sugar content, mozzarella is a staple for those following low-carb or ketogenic diets. It provides flavor, texture, and satiating protein and fat without impacting carbohydrate intake significantly. A typical one-ounce serving contains around 1 gram of total carbs, most of which are not sugar. This makes it a safe and delicious option for managing blood sugar and remaining in ketosis.

Conclusion

In summary, while all dairy products begin with lactose, the cheesemaking process for mozzarella—involving whey separation and bacterial fermentation—ensures the final product contains only trace amounts of sugar. Whether it's fresh or low-moisture, mozzarella is a very low-sugar, low-carb food that can be enjoyed as part of a balanced diet or specific dietary plan. Its minimal sugar content is a result of a natural, traditional process rather than a processed alteration. For more on the health benefits of dairy, the National Institutes of Health (NIH) is a great resource.

Outbound Link: Learn More – Shopping tips for lactose-intolerant people

Frequently Asked Questions

No, mozzarella cheese is not technically sugar-free, but its sugar content is extremely low. The sugar present is lactose, and most of it is removed during the cheesemaking process.

The sugar in cheese, specifically mozzarella, comes from lactose, which is the natural sugar found in milk. However, fermentation by bacteria consumes this lactose, resulting in minimal sugar in the final product.

Many people with lactose intolerance can tolerate mozzarella cheese in moderation. The cheesemaking process significantly reduces lactose, and individual tolerance levels for the small amount that remains can vary.

No, mozzarella is not high in carbohydrates. A one-ounce serving typically contains only about 1 gram of total carbohydrates, making it a low-carb food.

Yes, fresh mozzarella typically contains slightly more lactose than low-moisture versions because it retains more moisture and has a shorter production time. However, both are considered low-sugar.

To produce lactose-free mozzarella, the enzyme lactase is added during the cheesemaking process. This enzyme breaks down the lactose into simpler, more easily digestible sugars, resulting in a product without detectable lactose.

Mozzarella generally has a moderate to low lactose content compared to cheeses like cottage cheese but higher than aged, hard cheeses like Parmesan, which have virtually no lactose.