Preparing milk for trace analysis of contaminants and residues can be cumbersome.

The well-known methods such as Quechers or Quppe require time, extraction agents and personnel and are potentially associated with a risk of contamination.




Our FraMiTrACR® fractionation unit offers a new passive method for separating raw milk phases that does not require any additional extraction agents. For the first time, it enables a cost-effective just-in-time analysis of milk raw materials for various residues and contaminants, such as chlorate and perchlorate (C/PC) or antibiotic substances (AB).



Unprocessed raw milk is put into a fractionation unit (FraMiTrACR®) and simply centrifuged in a benchtop centrifuge. This separates milk into the phases “water” and “fat/protein”.

More information can be found here.

The FraMiTrACR®

  • easy to use
  • safe separation
  • savings in labor and costs
  • suitable for different analytes
  • suitable for many benchtop centrifuges
  • no extractants or additives

The FraMiTrACR®

  • easy to use
  • safe separation
  • savings in labor and costs
  • suitable for different analytes
  • suitable for many benchtop centrifuges
  • no extractants or additives

Contact Person:
Dr. Christian Baumgartner

Product Data Sheet


The Function

Unprocessed raw milk is placed in a fractionation unit (FraMiTrACR®) and simply centrifuged in a benchtop centrifuge. This separates milk into the phases “water” and “fat/protein”.

In principle, different sample volumes up to 10 mL can be processed. We examined many variants and found the following parameters as optimal:

Fixed-angle rotor: 10 mL raw milk | 30 minutes | 2.000 x g
Swing Out– rotor: 5 mL raw milk | 30 minutes | 4.000 x g

With both settings, about half of the supplied sample volume could be obtained as the water phase.

In direct comparison to established sample preparation methods such as Quechers and Quppe, passive sample preparation with FraMiTrACR® results in significant savings in working time and thus personnel costs. In addition, the complete avoidance of extraction solvents or other additives leads to further savings in personnel costs and in the laboratory process chain, while at the same time eliminating the risk of unwanted contamination.


Modern materials and separation techniques make it possible to process milk for residue analysis in a short time and without great effort, without the addition of extraction agents or other additives. With one of our FraMiTrACR® fractionation units and your benchtop centrifuge, you can easily save time and money.

How much time and effort can I save by using the FraMiTrACR®?

Depending on the method used for a target analyte, sample preparation takes a defined amount of time for active and passive working steps. This time can be shortened with the help of FraMiTrACR®. Let us demonstrate this by using the example of characterizing inhibitory substances.

Suppose the laboratory wants to test 16 milk samples for the antibiotic drug groups penicillins, cephalosporins, macrolides, sulfonamides, tetracyclines and quinolones. In this case, a laboratory employee needs about 6 hours to actively produce the final extracts for the individual groups of antibiotic compounds for testing.

Due to its special properties, the FraMiTrACR® passively separates the 16 milk samples into the phases “water” and “fat/protein”, for all the active antibiotic groups mentioned, within 30 minutes.

Also compared to the Quppe method, the sample preparation time for defined target substances can be reduced by clearly more than 50%. For testing chlorate/perchlorate in milk samples, the FraMiTrACR® only needs 9 minutes of active working time and 15 minutes of passive working time for the preparation of milk samples. In contrast, the Quppe method requires more than 80 minutes for the same number of samples.

But not only the working hours and the effort play an important role in the laboratory. The feasibility and quality of the method are also often decisive. Since the FraMiTrACR® does not require any additional tools or solutions and the work steps hardly allow any errors, preparation using the FraMiTrACR® ensures permanently stable results.

The extensive renunciation of extraction agents and other substances is also good for the environment and your budget.

Where can I get the FraMiTrACR®?

You can purchase the FraMiTrACR® from pureMilk analytical GmbH. Write us an e-mail to or call us on +49 171 8462612 (Dr. Christian Baumgartner).

Which sample types can I process with the FraMiTrACR®?

The FraMiTrACR® has been developed especially for raw milk samples. Sample preparation of raw milk in the conventional way before was complicated and time-consuming due to the complex composition of milk.

With the help of the FraMiTrACR®, preparation of raw milk is now quick and easy. But a wide variety of milk samples arrive in a laboratory. We have therefore tested the FraMiTrACR® with skim milk, whole milk, raw milk, cream and reconstituted skimmed milk powder, whole milk powder, whey powder and even lactose as well as baby food. We have successfully produced a final extract for further analyses for all sample types.

Can the FraMiTrACR® prepare samples other than raw milk?

Basically yes, if certain conditions are met. It is best to send us an e-mail with your specific request so that we can individually support you.

Which technique can I use to analyze the aqueous phase from the FraMiTrACR®?

In our investigations, we analyzed FraMiTrACR® extracts using IC-CD and LC-MS/MS. However, our extracts can also be used for other analytical devices and methods. It is best to send us an e-mail with your specific request so that we can support you individually.

Which laboratories are already using the FraMiTrACR®? Are there reference customers?

The FraMiTrACR® is still brand new and has just appeared on the market. In the validation, we worked closely with the Milchpruefring Baden-Wuerttemberg e.V., which is available to you as a reference customer and contact point. Contact Dr. Markus Albrecht, with an e-mail ( or by telephone (+49 7021 505203).

Are there any publications on the FraMiTrACR®?

The FraMiTrACR® has now been presented at a number of conferences and events. For more information, please have a look to our NEWS section.


Christian Baumgartner (63) and Jan-Michael-Steils (38) met in 2018 in the dairy industry. Initial ideas to utilize modern separation processes for sample preparation in milk analysis led to a joint project in which they quickly learned to appreciate each other. In February 2021, they founded pureMilk analytical GmbH together, with which they have set themselves the goal of introducing the fractionation of milk into the practice of checking residues in milk and thus opening up great potential for saving time and money.

Dr. med. vet. Christian Baumgartner

vet, author, journalist

see CV

Jan-Michael Steils

Jan-Michael Steils

vet, product developer, farmer

see CV



Do you have any questions or would you like to know more? Then write to us!

pureMilk analytical GmbH
Freyunger Straße 15 · D-94065 Waldkirchen
Telefon: +49 8581/9882625 · Mobil: +49 171/8462612