Lactose, SUGAR MILK, Aletobiose, β-Lactose, LACTIN, Osmolactan, Galactinum, 63-42-3

Chemical & Physical Properties

Synonyms:

Lactose, a major sugar in the milk of most species, could regulate human’s intestinal microflora.

The main sugar in milk, about 5% of cow’s milk is lactose. In human milk, it’s over 7%. Lactose provides great nutritional value from an early age. It is an integral part of baby milk formulas for infant nutrition. It is also used for many other applications.

 The role of lactose in fooD

Lactose is part of the carbohydrate family. This disaccharide, empirical formula C₁₂H₂₂O₁₁, is broken down in the gut by an enzyme, lactase, which provides two simple sugars: one molecule of D-glucose and one molecule of D-galactose.

The effects of galactose on our bodies

Although glucose is present in many foods, lactose is the sole source of galactose in our diet. And yet this is a molecule known for its biological benefits and its role in the construction of nerve tissues. Galactose is involved in the composition of nerve-tissue sphingoglycolipids (cerebrosides, gangliosides and mucoproteins) essential for the functioning of nerve cells.

For example, gangliosides present in the external plasma membrane act as membrane receptors and are highly concentrated in the ganglion cells of the central nervous system. They are thus involved in protecting membranes from the external environment.

The benefits of lactose

Recent studies highlight the role of lactose in the bodily absorption of minerals such as calcium, copper or zinc in infants.

Lactose is also believed to promote the growth of intestinal bifidobacteria, which fight the decline of certain immune functions associated with aging.

 In what areas is lactose used?

In infant nutrition

Breast milk contains 50% more lactose than cow's milk. It is therefore an essential ingredient in infant nutrition. When a baby is unable to be breastfed, it is fed with infant milk formulated to meet its needs as closely as possible, taking breast milk as a model. Formulators use refined lactose crystals to make infant milk.

This “refined lactose” has a higher degree of purity (99.4%) than “edible lactose” (99.0%). This difference in purity is observed in a more pronounced whiteness.

In the food industry

In the food industry, lactose is used for many reasons; for example, to improve the taste and texture of food. Because this sugar crystallizes better than dextrose and sucrose, it is used in the manufacture of confectionery and chocolate bars.

Food lactose is also widely used in bakeries, since its low sweetness and low solubility promote caramelization. This feature is also used to standardize the color of chips and fries.

But lactose has many other properties of interest to the food industry:

• It has the property of fixing food fragrances and amplifying aromas
• It absorbs pigments and is used to prepare food dyes
• It facilitates drying and dispersion
• It has emulsifying properties

 In the pharmaceutical industry

Lactose is one of the main pharmaceutical excipients. Due to its properties, it is used in the manufacture of tablets or capsules:

• As a filler to increase the volume of tablets
• As a binder for tablets
• It facilitates the administration and effect of the drug

In the cosmetics industry

Finally, in the cosmetics industry, lactose can also:

• Play the role of humectant to maintain moisture in the product
• Be used as a skin care product

What is lactose?

Lactose is a natural sugar that is present in cow’s milk and breast milk.

Lactose is obtained by a technical process (ultra-filtration, crystallisation and drying) from the whey of cow’s milk. This technology enables the production of a highly pure product.

As a sugar, lactose belongs to the carbohydrates group, as do fructose and glucose, for example. Lactose consists of two different sugar moecules, one molecule being galactose and the other being glucose.

In relation to conventional household sugar, lactose is split relatively slowly and can therefore reach deeper areas of the intestines, where it has a positive effect. Lactose gently regulates digestion.

Lactose is partially fermented in the intestines. The resulting lactic acid ensures healthy intestinal flora and simultaneously stimulates intestinal movement. Furthermore, lactose also promotes the intake of calcium and zinc from the intestine.

Lactose and BSE

According to todays knowledge, it has so far not been possible to transfer the BSE pathogen onto milk. There is therefore no need to worry about consuming milk or milk products.

Lactose is a natural sugar that's found in milk.

It is a carbohydrate. Structurally,

it is a disaccharide— a sugar molecule that’s composed of two simple sugars: glucose and galactose. Lactose is an important source of energy for babies, and it is also commonly used in food processing and pharmaceutical drug manufacturing.

Lactose is one of the major components of milk. Structurally, it is a disaccharide— a sugar molecule that’s composed of two simple sugars. Glucose can be found in many other food substances, but lactose is the only known source of galactose.

Lactose is white and odorless, and you may sometimes see or hear it referred to as "milk sugar." Lactose is only found in milk from mammals, so plant-based milk products like almond milk and soy milk don’t contain it.

The enzyme lactase helps the human body digest lactose. It does this by breaking and splitting lactose into glucose and galactose, a process that prepares these sugars for use as energy by the body.

Uses

Lactose has several uses, including drug manufacturing, food processing, and fermentation.

Pharmaceutical Uses

Lactose is widely used in the pharmaceutical industry in the preparation and manufacturing of drugs. Pharmaceutical-grade lactose is produced from whey—the liquid that’s left after milk has been curdled and strained during the making of cheese.

In most of its applications, lactose is used as an excipient (inactive ingredient). Its primary purpose is to aid the delivery of the active ingredient in the body. It’s mostly used in tablets, capsules, and dry powder inhalers.

Lactose is present in about 60-70% of all pharmaceutical dosage forms—like capsules, tablets, syrups, creams, and pastes.1 And about 45% of drugs contain a combination of lactose and microcrystalline cellulose (MCC).

Some of the roles lactose performs in drugs are:

• It acts as a filler: Sometimes the active ingredient in a drug is present in very small quantities. Fillers like lactose bulk up the drug, helping it flow better. Fillers also make it easier to measure the active ingredient in drugs.
• It acts as a binder: Lactose binds pills together by helping the other ingredients in a tablet mix and stick together.

Some of the characteristics of lactose that make it work well for these purposes are its blandness, chemical and physical stability, easy availability, compatibility with active ingredients, and ability to dissolve in water. 

Pharmaceutical-grade lactose is produced and processed to meet industry purity standards.

Food Processing

Lactose is used in several facets of food processing. Edible lactose that’s used in food processing is also mostly produced from whey.

It’s used in seasonings and baked goods due to its ability to carry colors and flavors well. It’s also added to foods and edibles like ice cream, skim milk, condensed milk, dry soups, coffee creamers, chocolate and candies, meat products, and canned fruit and vegetables.

When added to food, lactose may reduce cost and regulate sweetness.

Fermentation

Lactose is fermented to produce foods like cheese, yogurt, kefir, and acidified (sour) milk. Lactose is also fermented to produce lactic acid, which has a number of uses in the pharmaceutical, cosmetic, and food industries.

The process of fermentation involves adding lactic acid bacteria (and less commonly, yeast) to milk or to a milk product.

The Benefits of Fermented Foods

Bacterial Identification

In the clinical laboratory, the ability of bacteria to ferment lactose might help differentiate which bacterial species is causing an infection, such as food poisoning. For example, Escherichia coli ferments lactose while most Salmonella species do not.2

Cutting Agent

Lactose is commonly used as a cutting agent for illegal recreational drugs. Cutting agents are chemicals or drugs that are used to dilute and add bulk to recreational drugs.

The use of cutting agents is prevalent in illegal drug production, and the substances used for this process are typically less expensive than the recreational drug itself.

Health Benefits

Lactose has some health benefits for babies. Human breast milk is composed of 7.2% lactose, and this sugar provides up to half of the energy needs of breastfeeding babies. 

The lactose found in human milk has a beneficial effect on the development of microorganisms that live in the digestive tract of babies. It also helps babies absorb calcium better.

Lactose Intolerance

Lactose intolerance is when your body is unable to break down and digest lactose that's consumed in milk and other dairy products. The condition usually causes stomach discomfort.

Normally, lactase enzymes help to break down lactose. But when the body doesn’t produce enough lactase, you can have lactose intolerance. Lactose intolerance is very common, and it causes symptoms like bloating, diarrhea, cramps, and flatulence after consumption of dairy products that contain lactose.

Lactose intolerance is somewhat different from lactose maldigestion. With lactose maldigestion, the activity of the lactase enzyme is reduced—making lactose digestion difficult. But it causes little or no symptoms at all.

Lactose maldigestion affects 70-75% of people in the world.3

Some babies are born with a lactase deficiency and cannot digest lactose in breast milk or formula. Severe diarrhea is the major symptom of this kind of lactose intolerance, and babies with this condition may develop dehydration and weight loss. Often, lactose-free formula is recommended.3

A Word From Verywell

Lactose is a natural sugar that's present in dairy foods. It also has a number of uses in the food processing and pharmaceutical industries. While lactose has many health benefits for babies in their development stage, adults can do without it. So if you find that you’re lactose intolerant, you can avoid lactose-containing foods without the fear of adverse health effects due to lactose deficiency. Instead, look for foods that are labeled lactose-free or lactose-reduced. But keep in mind that there are other important components of dairy products—such as calcium and protein—that you need to make sure you are getting in adequate amounts.

Frequently Asked Questions

• What are the benefits of lactose-free milk?

  The main benefit in lactose-free milk is allowing people with lactose intolerance to enjoy milk and dairy products without triggering uncomfortable symptoms. However, it may also benefit people without a lactose intolerance, since lactose-free milk contains fewer added sugars and a lower calorie count.4

• What are the symptoms of lactose intolerance?

  The symptoms of lactose intolerance include bloating, gas, diarrhea, nausea, and stomach cramps or pain. These symptoms and their severity will differ among people with lactose intolerance. Symptoms usually occur within 30 minutes to two hours after ingesting lactose.5

• Does milk powder have lactose?

  Yes, milk powder (powdered milk) does have lactose. However, there are low-lactose varieties of milk powder that allow people with lactose intolerance to safely use them. These products will say "lactose-free" on the packaging.