Chapter 2: Production and forms of allulose
Allulose StoreBasics of allulose production
Allulose, also known as psicose, is a naturally occurring rare sugar, which can only be extracted in negligible quantities from natural sources – such as raisins, figs or maple syrup – and therefore its industrial production is essential.
In the modern food industry, allulose is produced almost exclusively from plant sources, most often corn starch, using biological conversion processes.
Natural sources vs. industrial production
Although allulose is naturally present in some fruits and plants, its amount in these is so low that it cannot be economically extracted.
Therefore, in the food industry, the starting material is usually corn starch, but other plant starches (such as wheat) can also be used.
The goal is to produce allulose in large quantities, with stable quality, and cost-effectively.
The process of industrial production of allulose
The process of producing allulose consists of several steps, during which the starch-based raw material is gradually converted into simple sugars and then into allulose.
Below we present the main steps in detail.
1. Raw material selection
The first step in production is selecting the right raw material.
Most often, corn or wheat are used, which contain large amounts of starch, i.e. complex carbohydrates.
2. Extraction and hydrolysis
Starch is extracted from the selected plant material using various methods (such as hydrolysis or enzymatic conversion), and then broken down into simple sugars, mainly glucose and fructose.
This step is important because fructose is required as a starting material to produce allulose.
3. Cleaning
The extracted sugar solution is freed from impurities (proteins, minerals, other unwanted components) through various purification processes.
This could include filtration, ion exchange or activated carbon treatment.
4. Enzymatic conversion
The fructose in the purified sugar solution is converted into allulose by special enzymes (e.g. D-xylose isomerase, psicose epimerase).
This is one of the most important steps, as this is where the structure of the fructose molecule is modified to produce allulose.
5. Filtration and concentration
The enzymatically converted solution is filtered again to remove any remaining impurities and then concentrated by evaporation or membrane filtration to ensure that the proportion of allulose in the solution is as high as possible.
6. Crystallization
The concentrated solution is cooled to promote the crystallization of allulose, allowing the allulose to separate from the liquid in solid form.
7. Separation and drying
The resulting allulose crystals are separated from the liquid by centrifugation or filtration and then dried to ensure that the final product is stable and can be stored for a long time.
8. Packaging and storage
Dried, pure allulose is packaged according to food safety regulations and then stored in a cool, dry place to preserve its quality and sweetening power.
So the entire industrial process looks like this
• Selection of starch-based raw materials (e.g. corn)
• Starch extraction and hydrolysis
• Cleaning
• Production of fructose
• Enzymatic conversion to allulose
• Filtration, concentration
• Crystallization
• Separation, drying
• Packaging, storage
Allulose forms: granular, crystalline and powdered
At the end of the industrial process, allulose can be marketed in several forms, depending on the intended use:
Granulated allulose
The appearance and texture of granulated allulose is very similar to traditional granulated sugar.
This form is excellent for baking and cooking, as it is easy to dose, dissolves easily, and can be a one-to-one replacement for sugar in most recipes.
Crystalline allulose
Crystalline allulose contains slightly larger crystals than the granulated version.
This texture can be beneficial for certain food applications, such as adding a unique texture to baked goods or sweets.
Powdered allulose
Powdered allulose is finely ground, with an almost powdery consistency.
This form is particularly suitable for sweetening drinks, as it dissolves quickly and completely, and is also ideal for making smooth frostings and creams.
The advantage of powdered allulose is that it does not leave a grainy texture, making it a perfect choice for sweetening mousses, glazes, and beverages.
Liquid allulose
Although not detailed in the sources searched, liquid allulose is also available from manufacturers, which is mainly used in beverage production, syrups, or for special food industry purposes.
Comparison of shapes
Form, Texture, Main area of use
• Granulated
Crystal Baking, cooking, sugar substitution
• Crystalline
Larger grain Unique texture, baked goods, sweets
• Powdered
Fine powder Drinks, icing, mousses, creams
• Liquid
Syrup Beverage production, syrups, special products
The choice depends on the desired texture, dissolution rate, and intended use.
Quality characteristics of allulose
Allulose for the food industry must meet strict quality requirements.
The final product is usually a white crystalline powder or granules with a purity of at least 99%.
The quality is checked by HPLC (high-performance liquid chromatography) testing, and the product also has ISO, HALAL, KOSHER certificates.
Packaging is usually done in airtight foil bags or paper drums, and the shelf life can be up to 2 years if stored properly.
Development of allulose production methods
There are three theoretical ways to produce allulose: plant extraction, chemical synthesis, and biological conversion:
Plant extraction
Extraction from natural sources (e.g. fruits, plants) is not economical from an industrial point of view due to the very low yield.
Chemical synthesis
Allulose is produced through chemical reactions, but this method is complicated, expensive, and difficult to purify.
Biological transformation (biocatalysis)
This is the most common industrial method, which uses enzymes to convert fructose into allulose with high efficiency and good purity.
The advantage of the biological conversion method is that it is more environmentally friendly, produces fewer by-products, and provides stable, high-purity allulose.
The use of allulose in practice
Various forms of allulose appear in many food products, such as:
• In baked goods and cakes, where the granular or crystalline form is most common
• In beverages, where powdered or liquid allulose dissolves quickly and leaves no aftertaste
• In icings, mousses, creams, where the advantages of the powdered form are exploited
• In protein bars, dietary supplements, where stability and low calorie content are the main considerations
The advantage of allulose is that it not only sweetens, but also preserves the functional properties of sugar: it adds volume, texture, and browning to products, thus providing an experience very similar to sugar.
Storage and shelf life
Allulose should be stored in a cool, dry place, away from direct light and heat, to maintain its quality and sweetness.
Packaging is usually done in airtight bags or paper drums.
With proper storage, the shelf life of allulose can be up to 2 years.
Summary
The industrial production of allulose is carried out using modern biotechnological methods, mainly from corn starch, through enzymatic conversion.
During the process, the starch is converted into simple sugars, then into allulose with the help of special enzymes, and finally purified, crystallized, and dried.
Allulose is available in several forms (granulated, crystalline, powdered, liquid), making it suitable for a wide range of food and home uses.
The quality requirements are strict, and the product's stability and shelf life are excellent.
Allulose is thus one of the most promising and versatile members of modern sugar substitutes.
