Which hygiene standards such as EHEDG and GMP should be observed for mixers used with dairy and milk powder?
For dairy and milk powder applications, hygienic design, validatable cleaning, controlled drying and documented process management are decisive in mixers. In practice, EHEDG, GMP, 3-A Sanitary Standards and the relevant requirements for food-contact materials are applied above all; with milk powder, dry hygiene, moisture control and dust explosion protection are added.
Relevant standards
EHEDG
EHEDG describes principles for hygienic design, that is plants that are easy to clean, can be inspected and are safe on the product side, without dead spaces, gaps or areas that are difficult to access.
GMP
GMP requires controlled, reproducible and documented processes. For mixers, qualification, cleaning evidence, maintenance, traceability and change control are particularly relevant.
3-A Sanitary Standards
3-A is particularly relevant in the dairy environment and defines hygienic requirements for the design, materials, surfaces and cleanability of food plants. Specific hygienic criteria exist for mixers and mixing systems.
Material conformity
Product-contact materials must be suitable for food contact and documented. Suitable stainless steels, food-compliant elastomers and tested plastics are typical.
Important design features
- Dead-space-free geometry that drains well.
- Smooth product-contact surfaces with few crevices and good accessibility.
- Hygienic seals and suitable shaft seals.
- Good cleanability and inspectability.
- Documented materials and surface quality.
Particularities with milk powder
Milk powder is hygroscopic, which makes moisture ingress and condensation particularly critical. After wet cleaning, the plant must be fully capable of being dried so that no caking or microbiological risks arise.
In addition, dust explosion protection has to be considered in the plant concept for fine powders. Strictly speaking this is not a question of hygiene standards, but in practice it is part of the safe design of milk powder plants.
Documentation
Important evidence includes material certificates, hygienic design evidence, cleaning validation, qualification documents and documented operating and maintenance processes. Depending on the project, riboflavin tests, ATP measurements or other cleaning checks can also be useful.
These are the standards amixon® meets – and this is how compliance becomes demonstrable
International standards on request
On request, amixon® industrial mixers meet the relevant international standards: the EHEDG guidelines (for dry and wet cleaning regimes), the FDA hygiene guidelines, the design rules of the 3-A Sanitary Standards, USDA requirements, GMP and the ATEX directives; pressure vessels are executed to ASME on request. Vertical and conical mixers (VM, HM, AM) can be used in FDA-compliant form as sterile mixers and reactors.
The design basis of conformity
Certifiability rests on hygienic design: mixing chamber and mixing tool welded free of crevices and ground smooth, the mixing tool supported only at the top (no lower shaft passage), dead-space-free standard connections with a discharge flap, Clever-Cut® inspection doors with the permanently dead-space-free OmgaSeal® seal, integrated washing lances for CIP/WIP. Product-contact materials range from austenitic stainless steels (1.4301, 1.4404, 1.4539 and others) to Alloy 59 and Hastelloy-C22.
Qualification and documentation
amixon® supplies more than apparatus: every mixer is a one-off, designed on the basis of the URS (user requirement specification) and manufactured in-house – quality control remains complete. amixon® assists on request with DQ, IQ and OQ; documentation and execution follow, on request, EU GMP and FDA 21 CFR Part 11. Integration follows the operator's validation concept from the URS through to commissioning.
In dairy and infant formula production, amixon® mixers are in use worldwide at manufacturers and contract manufacturers: vitamins, minerals, trace elements, encapsulated omega-3 fatty acids and probiotics are mixed in homogeneously and gently downstream of the spray tower – without destroying agglomerates.
Manufacture in Paderborn as the quality foundation
amixon® develops and manufactures exclusively at the Paderborn works, with the greatest depth of fabrication and all components from Germany. As a certified welding company with European, Japanese, Korean and American qualifications, amixon® designs every apparatus as a one-off on the basis of the operator's URS; quality control remains entirely in-house, and every specification is verifiable down to component level. This manufacturing sovereignty also secures long-term supply: every component can still be reproduced decades later.
Product protection as a system property
amixon® mixers operate at low speed: the circumferential speed of the tools is adjustable between approximately 0.8 and 3.5 m/s, and mixing takes place through SinConvex® forced restratification – upwards at the periphery, downwards under gravity in the centre – with no throwing, impact or crushing zones and no appreciable heat input. Sensitive structures, coatings and agglomerates are preserved; where targeted de-agglomeration is required, cutting rotors can be switched on to act in a locally confined manner, without stressing the entire batch.
Verification in the amixon® pilot plant
amixon® checks in advance in the pilot plant whether the specific formulation delivers the expected results: 35 test units, trials with the original product under real conditions, carried out, evaluated and documented jointly – as a robust basis for decision-making before the investment.