Which certifications and hygienic design standards, for example EHEDG, are relevant for milk powder mixers?
For milk powder mixers, hygienic design standards, food contact conformity and explosion protection requirements are the relevant considerations above all. In practice it is less a matter of a single overall certification than of demonstrating that the machine is hygienically constructed, readily cleanable, materially conformant and safe for the respective application.
Relevant standards and evidence
EHEDG is one of the most important reference frameworks for hygienic machine design in the food sector. For milk powder plants, the principles for hygienic construction and dry products are particularly relevant, because powder plants react sensitively to residues, caking and the ingress of moisture.
The 3-A Sanitary Standards are relevant above all for the US market and the dairy environment. They address hygienic construction, materials, seals and cleanability; they are therefore particularly important where international customers, audits or dairy applications play a role.
EN 1672-2 and EN ISO 14159 provide the general constructional basis for hygienically designed machines and cleanability. They are not "certificates" in the narrower sense, but they are important standards for hygienic design.
Food contact conformity under EU law is equally central, in particular via (EC) 1935/2004 and the appropriate material regulations for plastics, elastomers and coatings. What matters here is that no substances of health concern migrate and that the odour, taste or composition of the milk powder is not impaired.
FDA conformity is relevant where plants or components are supplied to the USA. What matters above all is the conformity of the product-contact materials and seals with the requirements applicable there.
ATEX and explosion protection must not be overlooked with milk powder, because it can be a combustible dust. Depending on the plant, zone classification, avoidance of ignition sources and constructional protective measures are to be taken into account.
What matters in the construction
For milk powder mixers, low-dead-space geometries, complete dischargeability, smooth surfaces and hygienically designed seals are decisive above all. Documented materials, clean weld seams and a cleaning concept that suits the application are equally important, usually dry cleaning and in some cases WIP or CIP.
With powder applications, dry cleanability is particularly important, because moisture can encourage residues, lump formation and microbiological risks. It is therefore not only the cleaning itself but also the avoidance of caking and product carry-over that is a core point of hygienic design.
The certifications and hygiene standards amixon® meets
amixon® combines international regulatory conformity with hygienically designed apparatus and gentle mixing technology. The requirements are not merely met formally. They are integrated into the plant by design. Compliance, cleanability, residual discharge, mixing quality and validatability can thereby be demonstrated in production operation.
amixon® industrial mixers can be adapted to various international standards. Depending on the requirement, designs according to EHEDG, FDA, 3-A, GMP, USDA, ATEX and ASME are possible. The plants are therefore suitable for regulated industries. These include in particular the food, pharmaceutical and process industries.
Vertical and conical mixers can also be executed as sterile mixers or reactors. The construction can be FDA-compliant in this case. This broadens the field of application of the plants.
The basis is a consistent hygienic design. The mixing chamber and mixing tools are welded free of joints. The weld seams are hygienically ground. This creates smooth and readily cleanable surfaces.
The mixing shafts are arranged vertically or at an incline. They are supported exclusively in the upper region. No additional shaft passage is therefore required in the product-contact area. Critical sealing points are reduced.
Standard connections, discharge flaps and inspection doors are likewise executed in a hygienic manner. Dead spaces are minimised by design. Inspection doors can be fitted with the OmgaSeal® seal. Integrated washing systems support CIP and WIP processes.
Special amixon® technologies are available for residual discharge. These include the ComDisc® tool for flat-bottom mixers. The tool lowers during discharge. It conveys remaining product purposefully to the outlet. The residual quantity in the mixing chamber is thereby reduced.
SinConcave® and SinConvex® mixing helices combine mixing action and discharge performance. They are particularly suitable for free-flowing products. Even with inclined apparatus geometries they support extensive residual discharge. Existing machines can in part be retrofitted with these helix geometries. This can extend the service life of existing plants.
A further focus is safe accessibility of the mixing chamber. Inspection doors with OmgaSeal® sit close to the product area. The adjoining dead spaces therefore remain small. The construction facilitates inspection, cleaning and maintenance.
The KwickKlamp® closure allows opening and closing with little effort. At the same time the closure is of self-locking design. This supports safe and hygienic sealing.
The WaterDragon® system is available for automated wet cleaning. Programmable washing nozzles clean the mixing chamber. The nozzle movement and the washing sequence can be adapted to the plant. After cleaning, the interior is dried with warm air. The mixing tool rotates slowly during this.
Cleaning remains confined to the interior. This is particularly relevant in sensitive dry mixing processes. The sequence is reproducible and controllable. Cleaning time and media consumption can be set purposefully.
Alongside hygiene, product protection is an essential design aspect. amixon® mixers operate at low rotational speeds. Typical circumferential speeds lie between approximately 0.8 and 3.5 m/s.
The SinConvex® mixing helix generates a defined forced restratification. The product is conveyed upwards in the outer region. In the centre it flows downwards again under gravity. This creates a three-dimensional product flow.
The mixing action is intensive yet mechanically gentle. Pronounced throw, impact and crushing zones are avoided. The heat input remains low. Sensitive agglomerates, coatings and fragile product structures can be preserved.
Additional cutting rotors can be used for targeted deagglomeration tasks. These act locally in the mixing chamber. The entire batch is therefore not permanently subjected to high shear energy. Intensity and duration of use can be adapted to the product.
Mixing quality is also an important design parameter. A high degree of homogeneity can be achieved after just a few tool revolutions. Conical mixers can achieve good mixing qualities even at low fill levels.
This is particularly important with high-value and functional ingredients. Typical applications are found in the milk powder, infant food and pharmaceutical industries. Small quantities have to be distributed evenly there.
Typical components include vitamins, minerals, trace elements and probiotics. Sensitive fat components can also be blended in. The product structure and the functional properties are to be preserved in the process.
A further quality factor is the depth of manufacture at the Paderborn site. amixon® develops and produces the plants at this site. Components from Germany are used in doing so.
Every apparatus is designed on the basis of the operator's requirements. The User Requirement Specification, URS for short, forms an important planning basis. The plant is therefore designed and manufactured on a project-specific basis.
Quality control, documentation and evidence remain in-house. This facilitates traceability. At the same time, the depth of manufacture supports long-term spare parts supply. Components can be reproduced even after many years of operation.
amixon® additionally accompanies the qualification and validation of the plants. The support can encompass Design Qualification, Installation Qualification and Operational Qualification. These steps are referred to as DQ, IQ and OQ.
Documentation and execution follow, on request, requirements such as EU GMP and FDA 21 CFR Part 11. The specific implementation depends on the operator's requirements and on the field of application of the plant.
Trials can be carried out in the amixon® pilot plant before the investment. 35 test units of various sizes are available there. The trials are carried out with the original product.
Real fill levels, batch sizes and process conditions can be taken into account in doing so. Mixing quality, product protection, residual discharge and cleanability are examined, among other things. Energy input and reproducibility can also be assessed.
The trial results are evaluated and documented. They serve as the basis for the later machine design. Technical and economic risks can thereby be reduced before the investment.
amixon® understands compliance as a constructional system property. It arises from the interplay of apparatus design, manufacture, documentation and process evidence. Regulatory conformity is therefore not described by certificates alone. It is supported by the technical execution of the plant.
The combination of international standards, hygienic design, gentle mixing technology and a high depth of manufacture is suited to demanding production processes. This applies in particular to applications in food, dairy, infant formula and pharma.