Gluten-free products

The production of gluten-free foods is now one of the most challenging areas of the food industry. Whilst gluten-free products were originally aimed exclusively at people with coeliac disease or a diagnosed gluten intolerance, this market segment has expanded significantly in recent years. Consumers increasingly associate gluten-free foods with a health-conscious diet, high product quality and innovative recipes. Consequently, demand for high-quality baking mixes, protein products, snacks, instant products and functional food mixes is growing steadily. Challenges in production and requirements for industrial mixing technology.

For manufacturers, however, this development places significantly greater demands on production. In traditional cereal products, gluten fulfils a wide range of technological functions. It provides elasticity, stability, water-binding capacity and a uniform pore structure. If gluten is removed from a recipe, these properties must be replaced by a precisely balanced combination of different raw materials.

The production of gluten-free products therefore usually begins with a complex powder mixture. It is at this stage that it is determined whether the final product will possess the desired properties. An uneven distribution of individual components can lead to significant variations in quality and affects, amongst other things, flavour, texture, water absorption and baking behaviour.

For this reason, industrial mixing technology is now one of the most important process steps in the production of gluten-free foods. Modern industrial powder mixers, food mixers and powder mixers for bulk materials enable the reproducible homogenisation of a wide variety of raw materials, thereby making a crucial contribution to product quality.

The global market for gluten-free foods has been growing steadily for years. In addition to medical reasons, changing dietary habits and the demand for functional foods are key factors driving this trend. At the same time, the variety of products on offer is increasing. Whereas in the past the range consisted mainly of gluten-free breads and flours, it now encompasses almost all product groups within the food industry.

What they all have in common is that they are based on complex dry mixtures, the quality of which depends directly on the mixing process used.

As product variety increases, so too do the demands on flexibility, process reliability and cost-effectiveness. Production lines often have to switch between different recipes whilst meeting the highest hygiene standards. Particularly in the case of gluten-free products, it is essential to reliably prevent cross-contamination.

Unlike traditional wheat-based products, gluten-free recipes consist of a wide variety of different ingredients, each of which fulfils specific technological functions.

Typical basic ingredients include various gluten-free flours such as rice, maize, millet, buckwheat or oat flour (certified gluten-free). These are supplemented by starches derived from potatoes, tapioca or maize, which have a significant influence on the texture and water-binding properties.

In addition, a wide range of functional ingredients are used:

• plant-based proteins
• dietary fibre
• thickening agents
• emulsifiers
• enzymes
• raising agents
• minerals
• vitamins
• natural flavourings

From a process engineering perspective, this presents a particular challenge. Whilst rice flour, for example, has a comparatively low bulk density, potato starches or mineral mixtures often exhibit completely different flow properties. Added to this are significant differences in particle size, particle shape, dust generation and moisture absorption.

For a powder mixer, this means that all components must be distributed evenly, despite their differing physical properties. At the same time, sensitive ingredients must not be mechanically damaged or adversely affected by excessive shear forces.

In many production facilities, the mixing process is often regarded as a simple step in the process. In fact, however, it is one of the key quality parameters in the entire food production process.

Inadequate powder homogenisation can have numerous consequences:

• variations in baking characteristics within a single batch
• fluctuating flavour
• uneven colouring
• localised over-concentrations of additives
• reduced solubility
• segregation during transport and storage
• increased wastage
• complaints from end customers

The aim of any industrial mixing process is therefore to produce a statistically perfectly homogeneous mixture. This is particularly true when micro-components such as vitamins, minerals or enzymes are added in very small quantities.

Even ingredients making up less than one per cent of the total must be evenly distributed throughout the product after the mixing process. This requirement places high demands on the design of an industrial powder mixer, as mixing does not depend solely on the mixing time. The product flows generated within the mixing chamber are equally crucial.

The requirements for a modern industrial powder mixer have changed significantly in recent years. Whilst high throughput rates used to be the main priority, product quality, energy efficiency and hygienic plant design are now becoming increasingly important.

A modern food mixer should combine the following features:

• very high mixing homogeneity
• short mixing cycles
• gentle mixing of products
• processing of a wide variety of bulk material
• incorporation of liquids
• hygienic design in accordance with EHEDG principles
• complete discharge
• low residual quantities
• easy maintenance
• high energy efficiency; reproducible batch quality

Avoiding cross-contamination is of paramount importance, particularly in the gluten-free food sector. Smooth surfaces, designs with no dead spaces and rapid cleaning all help to ensure that product changeovers can be carried out safely and cost-effectively.

The production of gluten-free foods places particularly high demands on the mixing technology used. Different bulk densities, varying particle sizes and sensitive functional additives require a mixing system that ensures both a high degree of mixing homogeneity and gentle processing of the product. Against this backdrop, innovative mixing processes are becoming increasingly important.

With the Glaxiaris®, GloMix has developed an industrial powder mixer that has been specifically designed for demanding mixing processes in the food industry. The system is suitable for processing powders, granules and bulk materials and is used, amongst other things, for baking mixes, spices, protein powders, instant products and functional food blends.

At the heart of the Glaxiaris® is its spherical mixing chamber, combined with a mixing axis inclined at an angle of approximately 23°. This design principle generates three-dimensional product movement, in which all product particles are continuously redistributed. Unlike conventional mixing systems, this results in virtually no dead zones, meaning that even raw materials with very different physical properties can be reliably homogenised.

This mixing principle offers significant advantages, particularly in gluten-free recipes. Flours, starches, plant-based proteins and functional additives often have different particle sizes, bulk densities and flow properties. Whilst conventional mixing systems sometimes tend to suffer from segregation or uneven concentrations under these conditions, the Glaxiaris’s three-dimensional product movement ensures thorough and uniform mixing of the entire batch.

A further advantage is the gentle handling of the products. As the mixing process is carried out predominantly by the movement of the entire product volume and high shear forces are avoided, sensitive ingredients such as enzymes, vitamins, probiotics and natural flavourings largely retain their functionality. This is particularly important in the case of high-quality gluten-free baking mixes and functional foods.

In addition to dry mixing, the Glaxiaris® also allows for the controlled addition of liquid components during the mixing process. Vegetable oils, lecithins or liquid flavourings can be incorporated into the powder mixture in a finely dispersed form. This ensures uniform wetting of the particles without the formation of agglomerates or locally over-moistened areas. This improves both the mixing quality and the subsequent processability of the product.

From a hygiene perspective, too, the Glaxiaris® meets the requirements of modern food production. Its design allows the mixing chamber to be emptied almost completely, thereby reducing product losses. At the same time, the hygienic design facilitates cleaning and helps to prevent cross-contamination – a crucial aspect in the production of gluten-free foods.

The Glaxiaris® thus meets the key requirements of a modern industrial powder mixer for the food industry. Particularly in the manufacture of gluten-free products, the combination of high mixing quality, gentle processing and hygienic design helps to ensure reproducible production processes and consistently high product quality.

The quality of gluten-free foods is largely determined by the homogeneity of the powder mixtures used. As the recipes consist of numerous raw materials with different physical properties, the selection of a suitable powder mixer is of crucial importance. Today, modern industrial powder mixers must not only achieve a high standard of mixing quality, but also ensure short processing times, meet hygiene requirements and handle the product gently.

With its innovative mixing principle, the Glaxiaris® offers a high-performance solution to these requirements. Thanks to the three-dimensional product movement, the high mixing homogeneity and the hygienic design, the system is particularly well-suited to demanding applications in the food industry. In the manufacture of gluten-free baking mixes, protein powders or functional dry mixes, the Glaxiaris® thus makes a significant contribution to efficient, safe and high-quality production.

Glomix informiert