Is It Possible to Remove Sugar From Milk? Yes, With Specific Methods

November 16, 2025 •

5 min read

Milk's natural sugar is a disaccharide called lactose. While you can't simply stir it out, it is possible to remove sugar from milk using specific processes developed by food scientists and available to consumers. This makes dairy products accessible to the approximately 68% of the global population with lactose intolerance.

Quick Summary

The natural sugar (lactose) in milk can be removed or broken down using industrial filtration, enzymatic hydrolysis, or simple at-home methods. This yields lactose-free milk, which can have a slightly different taste but retains its core nutritional value.

Key Points

Lactose is Milk's Sugar: The natural sugar in milk is lactose, a disaccharide composed of glucose and galactose, which is what is modified or removed.
Enzymatic Hydrolysis (At-Home & Industrial): This method uses the lactase enzyme to break down lactose into simpler, more digestible sugars, resulting in a sweeter-tasting milk.
Membrane Filtration (Industrial Only): For a flavor closer to regular milk, industrial producers use ultrafiltration and nanofiltration to physically remove the lactose from the milk.
DIY Method Is Cost-Effective: You can make your own lactose-free milk by adding lactase enzyme drops to regular milk and refrigerating it, offering a convenient and cheaper alternative.
Taste Difference Depends on Method: Enzymatic hydrolysis results in a sweeter product, whereas filtration yields a taste profile much closer to original milk.
Processing Targets Lactose Intolerance: The primary motivation for removing lactose is to help people with lactase deficiency, but the process does not fundamentally alter the milk's other nutrients like protein, fat, and calcium.

The short answer is yes, it is possible to remove sugar from milk, though not in the same way you might strain sugar from a liquid. The 'sugar' in milk is actually lactose, a disaccharide that is naturally dissolved in the liquid. Removing it requires specialized techniques, which range from industrial-scale processes to simple, at-home methods using a special enzyme. The primary purpose for removing milk's lactose is to produce lactose-free dairy products for individuals who lack the enzyme lactase, which is necessary to digest lactose properly.

Understanding Lactose, the Sugar in Milk

Lactose is a disaccharide, meaning it's composed of two smaller sugar molecules: glucose and galactose. Unlike added sugars, lactose is an inherent component of milk and serves as a vital energy source for young mammals. For those with lactose intolerance, the body produces insufficient amounts of the enzyme lactase to break down this sugar in the small intestine. As a result, the undigested lactose travels to the large intestine, where gut bacteria ferment it, leading to uncomfortable symptoms like bloating, gas, and abdominal pain. Food scientists have developed effective methods to address this issue.

Industrial Methods for Removing Sugar from Milk

Commercial dairy producers employ several sophisticated techniques to create lactose-free products. These methods ensure consistency, safety, and a final product that closely resembles regular milk in texture and nutritional content.

Enzymatic Hydrolysis

This is one of the most common methods for producing lactose-free milk. The process involves adding the lactase enzyme to milk, which breaks down the lactose into its more digestible monosaccharide components, glucose and galactose.

The Process: The lactase enzyme is added to pasteurized milk and held at a specific temperature for several hours. This allows the enzyme time to break down the lactose. Afterward, the milk is typically re-pasteurized or ultra-pasteurized to deactivate the enzyme and ensure a long shelf life.
Effect on Taste: The resulting milk often tastes sweeter than regular milk. This is because glucose and galactose are perceived as having a higher sweetness intensity than lactose, even though the total sugar content remains the same.

Membrane Filtration (Ultrafiltration and Nanofiltration)

This method physically separates the lactose from the milk using fine-pored membranes. Unlike enzymatic hydrolysis, this process actually removes the sugar rather than just changing its form.

The Process: Milk is pushed through a series of specialized membranes under pressure. The pores in the membrane are large enough to let small molecules like water and some minerals pass through but small enough to trap larger components like fats and proteins. To remove lactose, nanofiltration is used, which separates the smaller lactose molecules from the rest of the milk components. Water and minerals are then returned to the protein and fat-rich concentrate to achieve the desired milk composition.
Effect on Taste: Because the lactose is physically removed, milk produced via this method doesn't have the sweeter taste associated with enzymatic breakdown, resulting in a flavor profile closer to regular milk. Some producers combine this method with enzymatic hydrolysis to achieve a taste closer to conventional milk.

How to Remove Sugar from Milk at Home

For a simpler, more cost-effective option, consumers can make their own lactose-free milk at home using readily available lactase drops.

Steps for At-Home Lactose Reduction

Purchase Lactase Drops: These can be found at most pharmacies or online retailers.
Add Drops to Milk: Follow the package instructions, which typically recommend a certain number of drops per liter of milk.
Refrigerate: The bottle should be shaken and then refrigerated for at least 24 hours to allow the enzyme to break down the lactose effectively. Waiting longer may break down more lactose.
Test for Conversion (Optional): For the truly curious, glucose testing strips can be used to see if the lactose has been converted into glucose and galactose. A positive test indicates the process is working.

Comparison of Lactose Removal Methods


Feature	Enzymatic Hydrolysis	Membrane Filtration	At-Home Enzymatic Method
Equipment	Industrial-grade pasteurizers, mixing tanks	Complex filtration units, pumps	Standard refrigerator, lactase drops
Process	Lactase enzyme added, held at temperature, re-pasteurized	Pressure-driven filtration through fine membranes	Lactase drops added to milk, time in fridge
Lactose Removal	Broken down into glucose and galactose	Physically separated and removed	Broken down into glucose and galactose
Taste Profile	Sweeter than regular milk	Less sweet, closer to regular milk	Sweeter than regular milk
Cost	Industrial scale, high upfront cost	Industrial scale, high upfront cost	Low cost, uses existing milk
Convenience	Highly controlled, consistent industrial process	Highly technical, industrial process	Very simple for consumers

Choosing the Right Method for Your Needs

For most people seeking lactose-free milk, purchasing a pre-made product from the supermarket is the easiest route. These products are carefully formulated for taste and consistency. For those who want a more cost-effective solution or need to reduce lactose in other dairy products like cream, the at-home enzymatic method is a great choice. Industrial filtration, while not accessible for the average consumer, is a critical process for manufacturers who aim to produce a product with a neutral taste profile more akin to regular milk, a key driver for products like certain cheeses and yogurts. Ultimately, the method of removing sugar from milk depends on the desired outcome—whether it is a slightly sweeter, enzyme-treated product or a filtered product that maintains its original flavor complexity.

Conclusion: A Matter of Method and Taste

In summary, the idea of removing sugar from milk is not a myth but a standard practice in the food industry for creating lactose-free products. The process involves either adding the enzyme lactase to hydrolyze the lactose or using high-tech membrane filtration to separate the sugar entirely. While both methods are effective, they produce different results in terms of taste and are undertaken at different scales. Consumers can also perform a basic version of the enzymatic method at home with lactase drops. This technological advancement has made it possible for millions of people with lactose intolerance to enjoy dairy, proving that milk's sugar content can indeed be modified with the right approach.

NIH.gov on Dairy Food Sugar Reduction

Frequently Asked Questions

The natural sugar found in milk is called lactose. It is a disaccharide made of two smaller sugar molecules, glucose and galactose.

When using membrane filtration, the lactose is physically removed, which reduces the total sugar content. However, with enzymatic hydrolysis, the lactose is simply broken down into smaller, simpler sugars, so the total sugar and calorie content remains the same.

Lactose-free milk made with the enzymatic method tastes sweeter because the lactase enzyme breaks down lactose into glucose and galactose. Our taste buds perceive these simple sugars as sweeter than lactose, even though the overall sugar amount is unchanged.

Yes, you can easily make your own lactose-reduced milk at home by adding lactase enzyme drops to a container of regular milk and refrigerating it for at least 24 hours.

Industrially, lactose is removed using two primary methods: enzymatic hydrolysis by adding the lactase enzyme, or membrane filtration (like ultrafiltration) to physically separate the lactose.

For individuals with lactose intolerance, lactose-free milk is a healthier option as it prevents digestive discomfort. For those without intolerance, the nutritional content is essentially the same as regular milk.

No, whether by enzymatic or filtration methods, removing or converting lactose does not typically affect the core nutritional value of milk, including its protein, calcium, and vitamin content.

The key difference is how the sugar is handled. The enzymatic method breaks the lactose molecule apart, keeping the components in the milk, while the filtration method physically separates and removes the lactose.