In the food industry, fats and oils are important raw materials for the production of a wide variety of products. A key quality parameter of any fat or oil is the Solid Fat Content (SFC) value. Nowadays the SFC value is measured using advanced NMR techniques.

The procedure to determine SFC has been documented in the standard ISO 8292:1991 (AOCS Cd 16b-93 for the US), which describes the precisely controlled sample conditioning and measuring procedures. In cooperation with industry, Da Vinci Europe Laboratory Solutions B.V. (DVE) has developed a robot system that automates all requirements.

A fat sample is taken from a production batch and is divided over a number of 150 x 10 mm glass test tubes. The sample type determines the number of test tubes to be used. Electronics control various peltier-effect heated/cooled tubes racks in a range of 0.0 – 80.0 ± 0.1°C, water/oils baths are no longer required. According to the ISO standard the operator positions the tubes in the 'in-tray' (60.0°C). From now on, the robot takes care of tube transfers to other trays, the NMR for final SFC reading, and discarding analyzed tubes.

After melting at 60.0°C, all sample tubes are cooled to 0.0°C in the following tray, then individual tubes are typically distributed to 10.0, 20.0, 30.0, 35.0, and 40.0°C trays. After a (ISO) specified time, the SFC value is determined by the NMR and the test tube is discarded.

Critical for the SFC measurement are the accuracy and stability of the tray temperatures, and the custom peltier-effect trays were designed to easily comply with the ISO standards.

Another critical factor is the period of time a tube resides in a tray. The ISO standard specifies these residence times to be in the range 1-180 minutes. The advanced DVE robot scheduling software guaranties accuracy, no matter where the tube is located

The DVE application software integrates NMR control SW (Bruker), temperature control and logging, all wrapped in a comprehensive easy-to-use operator interface. For example, the interface allows easy sample registration using barcodes and each barcode is used to certify all measured details per tubes including tray position, current temperature, origin and NMR results.

After SFC determination, a data set is stored in a local database for laboratory reporting and a sub-set of abstracted data is transmitted to the company LIMS.

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