Malt sugar (maltose, organic?, raw?)

Malt sugar is a breakdown product of starch that is created when grain germinates. Due to the higher temperatures used during production, malt sugar is no longer raw. Chemically, malt sugar is called maltose.

Use in the kitchen

Before using malt sugar in the kitchen, it is important to understand what type of sugar it is.

What is maltose? Where does maltose occur? What is maltose made of?

Maltose, also known as malt sugar, is a disaccharide. This means that it consists of two glucose molecules linked together. Maltose is found in free form in various raw and cooked fruits, grains, nuts and vegetables; including soy, sweet potatoes, watermelon, peaches and pistachios. ^18,10 Maltose can also be produced from starch through artificial biochemical processes or through natural processes - through enzymatic breakdown. The necessary enzyme is produced naturally, for example, during the germination of grains. The germinated grains produce enzymes that convert starch into sugar to promote the growth of the seedling. The namesake, malting, refers to the controlled germination of grain to produce malt for beer production, for example. ⁵

A particularly high level of maltose is found in processed foods. Hydrolysis occurs when heating or cooking; the breakdown of starch, cellulose and other polysaccharides. Therefore, the end product or the finished dish has a higher maltose content than the underlying food. A clear example of this process is ketchup. Raw tomatoes are much less sweet than heated and concentrated tomato puree. ¹⁸ For this reason, fried or baked sweet potatoes also contain a particularly high level of maltose. ⁹ The malt sugar contained in foods is not raw.

By the way, maltose is also formed when starch is digested. In the mouth, or more precisely in the saliva, amylase is used to break down starch into sugar. If you keep a salty cereal cracker in your mouth for too long, you can taste the formation of maltose. The biochemical breakdown of the polysaccharide starch, under the influence of the enzyme β-amylase, produces maltose (there are other enzymes with this ability). The enzyme maltase then breaks down the maltose into glucose. ^1,6,10 You will learn how to turn the maltose in the cereal into a syrup or granulated sugar in the following chapters.

Are malt sugar and grain sugar the same? No, the main difference between the two types of sugar lies in their chemical structure and origin. Grain sugar generally consists of glucose obtained from grain. Grain sugar is usually dried glucose syrup based on corn. Glucose, also called dextrose or grape sugar, is a simple sugar (monosaccharide). This sugar is the main energy supplier for the human body and plays a central role in metabolism. Glucose tastes sweet, but not as sweet as sucrose (table sugar), which consists of glucose and fructose. This is why grain sugar is particularly interesting for people who cannot tolerate fructose. Grain sugar made from dried corn glucose syrup can be found in stores, including organic quality. Glucose has a sweetness of 0.7. For comparison: The sweetening power of household sugar (sucrose) is 1, fructose has 1.5 and malt sugar 0.4. ¹¹

Corn sugar should not be confused with ' high-fructose corn syrup '. In this sugar, part of the glucose is converted enzymatically to fructose. In Europe, this syrup is called isoglucose. ¹¹

Which foods contain maltose ? Maltose is used commercially in baked goods, jams, breakfast cereals, confectionery, in beer brewing and in whisky production.

Malt sugar is rarely used in private kitchens in the western world. However, malt sugar is an integral part of Chinese cuisine. Meat dishes in particular are brushed with maltose to give them a brown crust. A classic dish is 'Peking duck'. In general, malt sugar offers a special viscosity/stickiness with less sweetness than most other types of sugar. It can be used for both sweet and savory dishes. The terms malt sugar and malt syrup are often used synonymously; however, there is a subtle but significant difference. Malt sugar is the colloquial term for maltose. While malt syrup can also contain other types of sugar such as fructose. Due to the very high maltose content, the term maltose is used, also often synonymously for rice syrup. The production of rice syrup illustrates very well the formation of maltose (rice could be replaced with other starchy plants such as potatoes or corn):

Homemade rice syrup Ingredients

(approx. 250ml syrup): 50 g wheat grains, 500 g sticky rice, water.

Preparation: First, soak 50 g of wheat in cold water overnight. The next day, spread the grain evenly on a baking tray lined with a tea towel. Now germination begins. To ensure the survival of the seedlings, you should spray them with water twice a day and store them at room temperature. After about two days, the seedlings will be visible; after a week, you should see the blades of grass (wheat belongs to the grass family).

Before harvesting the grass: soak 500 g of sticky rice in cold water overnight. Then steam the rice until it is soft and sticky. Now harvest the grass including the germinated seeds and wash it thoroughly. Mix the germinated wheat and 3 tablespoons of the rice to form a green paste. Add the mixture to the rice and stir well. The amylase in the germinated wheat converts the starch into maltose. In other words, into a shorter-chain carbohydrate, i.e. a sweeter molecule. Leave the porridge to warm for 6-7 hours at 40-50 °C (in a rice cooker, on the stove or in the oven). Cover the porridge so that the liquid does not evaporate. Then strain the liquid. Cook at a low heat for about an hour until the syrup has thickened. Allow to cool slightly and pour into a screw-top jar.

Attention: The malt sugar produced in this way is not raw. In addition, there is no guarantee that homemade malt sugar consists of 100% maltose. It may also contain traces of fructose. You can find more information under the ingredient rice syrup. If you want to use maltose in its pure form, you should use industrially produced products.

Vegan recipes with malt sugar can be found under the note: " Recipes that have the most of this ingredient ".

Purchasing - Storage

At major retailers such as Coop, Migros, Denner, Volg, Spar, Aldi, Lidl, Rewe, Edeka, Hofer, Billa, malt sugar (maltose) is only seen as an additive in a wide variety of foods. In organic supermarkets such as Denn's Biomarkt or Alnatura, malt sugar is not found in its pure form either, but is very much an ingredient or as a naturally occurring component.

Malt sugar is available online or in Asian shops that specialize in Chinese ingredients. The term is not always clear; extract, sugar and syrup are often used synonymously. Occasionally you can find products made from grains (rice, barley, corn) in organic quality, but then it is hardly pure maltose.

The availability of malt sugar varies depending on the size of the store, catchment area, etc. Our recorded food prices for the DA-CH countries can be found above under the ingredient image - and by clicking you can see their development at various suppliers.

Storage tips

Maltose, like any other type of sugar, must be stored in a dry place, protected from light and ideally airtight. This way, the maltose will last for years.

Ingredients - Nutritional values - Calories

Maltose is a disaccharide and is made up of carbohydrates. Pure maltose does not contain any other substances such as fats or proteins, nor vitamins or trace elements. Depending on its purity and form, maltose can still contain small amounts of vitamins. Maltose, which tastes less sweet, has 405 kcal/100g ²¹, almost the same number of calories as household sugar (387 kcal/100g). ¹⁹

Malt sugar does not contain any ingredients of animal origin: malt sugar (maltose) is vegan.

The complete ingredients of malt sugar, the coverage of the daily requirement and comparison values with other ingredients can be found in our nutrient tables. In the article Nutrients explained you will get a detailed insight into the topic.

Effects on health

Is maltose healthy? Like all sugars, maltose has both good and bad sides. Maltose provides a lot of quickly available calories; depending on the situation, this can be positive, but it can also be very unhealthy. However, it does not contain any important nutrients such as vitamins, minerals and fiber - they are empty calories, so to speak. ¹³

When cooking and frying, foods brown at different rates. The strength of the browning reaction varies depending on the type of sugar; malt sugar is very reactive in this respect. A chemical reaction during browning produces acrylamide. This substance is potentially carcinogenic. Even without the use of heat, it is believed that excessive consumption of sugar, especially fructose, promotes the development of cancer. ^6,10,12

The body quickly processes maltose into the monosaccharide glucose and can therefore absorb it quickly. ¹¹ This simple sugar supports cognitive performance and can temporarily improve memory performance. This is not surprising, as glucose (which can of course also be obtained from relevant disaccharides and starch) is the most important source of energy for the brain. The brain needs a constant supply of glucose from food. In fact, an adult's brain needs about 100 mg/min of glucose and infants need twice as much. ⁶ But you should also eat foods with a low glycemic index!

Maltose is an important substance in nature. However, excessive consumption, especially maltose in its pure form, is associated with health risks. Since maltose is quickly available to the body, blood sugar levels rise quickly: the glycemic index is high. A diet with an excessive intake of carbohydrates with a high glycemic index (GI) is associated with diseases such as diabetes or obesity. ^{14,15, 16}

Dangers - Intolerances - Side effects

Approximately 2% of people lack the enzyme maltase-glucoamylase. They cannot convert maltose into glucose and therefore suffer from chronic diarrhea. These people must avoid consuming malt sugar and starch. ⁶

People with diabetes should avoid maltose. The body breaks down this sugar into glucose and blood sugar levels rise quickly. ¹⁵

For people who cannot tolerate fructose: Although malt sugar only consists of glucose, products sold as maltose may also contain fructose. The terms maltose, malt sugar or malt syrup can be found on sugar products that do not necessarily contain maltose in its pure form.

Folk medicine - natural medicine

Malt sugar is traditionally used to make cough drops. Sucking the drops, also called malt sugar biscuits, is said to relieve coughing and catarrh of the upper respiratory tract. ⁴

Ecological footprint - animal welfare

The production of malt sugar is complex. ^5,6 And when you consider that the body produces maltose from starch itself, it is questionable whether it is worth the energy expenditure required.

Malt extract powder has a CO ₂ footprint of 4.26 kg CO2eq/kg. ²³ This is a large footprint, comparable to the average of pork (4.6 kg CO ₂ eq/kg) or cream (4.2 kg CO ₂ eq/kg). Honey in a jar has only half as large a footprint (2.0 kg CO2eq/kg), organic cane sugar has 0.9 kg CO2eq/kg and organic beet sugar has only 0.5 kg CO2eq/kg. ²⁴

On average, grain has a global water footprint of 1644 l/kg. Barley has an average of 1423 l/kg and malt 1950 l/kg. ²⁵ Unfortunately, we were unable to find out how much water is needed to process it into malt sugar. The water consumption of barley production is far higher than the average for growing vegetables (322 l/kg) or fruit (962 l/kg); however, the water footprint can still be classified as good. Nuts (9063 l/kg) or meat (e.g. chicken 4325 l/kg or beef 15,415 l/kg) have a much larger footprint. ²² Sugars that use less water are raw cane sugar (1666) from sugar cane (210 l/kg) or raw beet sugar (865 l/kg). ²⁵

For detailed explanations of various sustainability indicators (such as ecological footprint, _CO2 footprint, water footprint), see our article: What does the ecological footprint mean?

Worldwide occurrence - cultivation

Unlike corn syrup, the predominant grain-based sweetener today, malt sugar (malt syrup) has been around for several millennia. There is evidence that malt syrup and honey were the main sweeteners in China from about 1000 BC to 1000 AD. Table sugar was too expensive for rural populations, but malt syrup could be made from common grains such as rice or wheat. ⁷

Industrial production

The process begins with malting. Grains are first soaked in water. Barley is a popular grain because it produces unusually active and abundant malt enzymes. Enzyme activity is stopped by quickly drying the germinating seed, which kills the seed embryo. The malted grains are then ground. Soaked in hot water and mixed with cooked grains (unless it is a malt extract, in which case no cooked grains are added). The malt enzymes break down the long-chain starch contained in the cooked grains into shorter molecular chains - malt sugar is formed. What remains is a sticky, brown syrup. The taste differs depending on the technique. Malt sugar generally tastes like biscuit or honey, and is reminiscent of chocolate and coffee. ⁷ Such syrups consist of about 60% maltose. ⁵ To obtain maltose in its pure form, further chemical steps are required. The still unsplit starch in this syrup can be removed by precipitation using ethanol. The ethanol is then allowed to evaporate by heating. What remains is maltose. If you then dry this malt sugar, you get maltose crystals. ¹⁷

Further information

In addition to beer, Ovomaltine also contains barley malt. In Switzerland, this drink mix does not contain cane sugar, but internationally it does. Malt coffee contains the malt of various ingredients such as barley, rye, acorns or beech nuts and gives the coffee alternative a sweet taste. Malt is also often added to bread. By germinating the grain, it contains many enzymes and also sugars that improve the fermentation process in the bread. The malt reacts with various amino acids in the bread to create special flavors. ²⁰

Maltose is often confused with maltulose. However, maltulose is a naturally occurring chemical compound of reducing disaccharides and consists of glucose and fructose. In addition to the isomer isomaltulose, maltulose is also found in honey and beer. At high temperatures, existing maltose is converted into maltulose. If the maltulose content is low or the maltose to maltulose ratio is high, this indicates gentle preparation processes (low temperatures). ^2,3

Alternative names

In addition to the names 'malt sugar' and 'maltose', 'malt syrup' is also common. Strictly speaking, however, malt syrup is a different product. Malt syrup can consist largely of maltose, but it does not have to; unlike malt sugar. ⁸

In English, malt sugar is called 'maltose' or 'malt sugar'.

Other applications

In the biological laboratory, maltose is used to fill culture media and is also used to chemically produce lactic acid. ²⁰