The demand for gluten-free bakery products is rising - and not just because a growing number of people suffer from gluten intolerance, but also because food without gluten is seen as part of a trend towards healthy nutrition. The packing of gluten-free bakery products does however place special demands on the systems that are used.
Bread, bakery products and other food that contain gluten are taboo for those affected by celiac disease. Celiac disease is a chronic, autoimmune disorder, which is caused by a lifelong intolerance to the protein composite gluten. This is contained in cereals such as wheat, spelt, rye, barley, oats and green spelt, as well as in old types of wheat, such as emmer or einkorn wheat. Gluten-containing cereals and all food that contains these cereals, even in small traces, are unsuitable for those affected by celiac disease.
It is estimated that 70 million people(1) are affected by this food intolerance worldwide, of which 400,000 alone are in Germany(2) - a rising trend due to improved diagnosis and a growing awareness of the disorder. The only treatment for celiac disease is gluten-free nutrition for life.
Although the products on offer are still limited in some countries, a large number of manufacturers are now offering gluten-free food. The market volume for gluten-free products in Germany is around 40 million euros(3). In addition to inherently gluten-free food, there are also many new product formulations in which standard food products are imitated - but without the addition of gluten-containing ingredients. Such new product formulations can involve significant technological and scientific challenges, particularly when it is a question of achieving the sensory characteristics of the comparable gluten-containing product. The ingredients have to be selected on the basis of different criteria, e.g. their function in the product or the consequences of leaving them out, the costs and availability, their reaction with other ingredients, the predisposition to changes in the manufacturing process, or other features that make the product more attractive for the consumer.(4)
Many gluten-free bakery products can be manufactured with the equipment in a conventional bakery. The greatest challenge is ensuring that the statutory limit values are maintained, since bakery products can only be declared as “gluten-free”, if the gluten content does not exceed the limit value of 20 ppm (20 mg/kg). The danger of cross-contamination during production is particularly high. The operating parameters must not be automatically transferred from the conventional manufacturing process, since the baking or cooking conditions for example have to be optimised for gluten-free products. Most gluten-free bread and rolls are par-baked which can be stored under various conditions, i.e. frozen, chilled or at room temperature. The baking is completed prior to sale or immediately before consuming.
Gluten-free bakery products also place special demands on the packaging. The shelf life of gluten-free bakery products is generally very short due to the loss of moisture and aroma. The absence of gluten often leads to a more fluid dough or to bread with a brittle texture after baking, and such bread is paler and has other negative characteristics compared with a conventional product. If gluten-free bread is stored at room temperature, there is also a loss of quality due to mould formation or staling. Packs with modified atmosphere (MAP) are generally used to extend the shelf life of gluten-free products. Carbon dioxide (CO2) inhibits the development of yeast and bacteria, and it has an anti-fungal effect against mold. For this reason it is frequently used for packing bakery products, sometimes in conjunction with nitrogen as a supporting gas to reduce the diffusion of inert gas from the pack; the nitrogen is completely neutral in its effect on the packaged product. By reducing the oxygen content in the pack to less than one percent, the growth of yeast and many bacteria can be slowed down, while mold formation is completely prevented. Due to the different consistency between gluten-free and conventional gluten-containing products, the MAP mixture has to be individually tested for each formulation when packing gluten-free bakery products.
MULTIVAC packaging solutions are suitable for the efficient and reliable packing of both conventional and gluten-free bakery products. Thermoforming packaging machines of all sizes and outputs, equipped with a gas flushing system, are particularly suitable for these products. A mixing and control unit (gas mixer) precisely control the composition of the modified atmosphere from several component gases, although special pre-mixed gas mixtures are available for many bakery products. The benefits of thermoforming packaging compared with flow-wrapped packs, which are frequently used for bakery products, include a smaller consumption of inert gas and the ability to control the atmosphere in the pack more precisely by using barrier films. It is also of benefit to be able to load product more easily from above into the pack, particularly for products such as sliced loaves.
MULTIVAC also offers fully automated thermoforming packaging solutions for packing sliced bread and bakery products in large batches. Special handling modules are used for feeding and loading the bread slices. The integration of additional functions, such as inline labelling, printing and quality inspection, offers a high degree of process reliability. This is particularly important for consumers in the labelling or marking of gluten-free bakery products.
MULTIVAC provides ideal conditions for carrying out packaging tests in its Training & Innovation Center at its headquarters in Wolfertschwenden. It is there that customers have the opportunity to develop and test a wide range of packaging concepts for their products, such as pack types and product-specific gas mixtures for gluten-free bakery products.
(1) Source: Association of European Celiac Societies (AOECS)
(2) Source: Deutsche Zöliakie Gesellschaft e.V. (DZG)
(3) Source: Lecture by Dipl.-Ing. Udo Hanneforth at the 62. Conference for Bakery Technology 2011 in Detmold.
(4) Cf. New product development: The case of gluten-free food products. In: Gluten-free Cereal Products and Beverages, 2008, p. 413-431. Alan L. Kelly, Michelle M. Moore, Elke K. Arendt.