European Food Research and Technology

, Volume 245, Issue 2, pp 411–418 | Cite as

Vitamin D enhanced pork from pigs exposed to artificial UVB light in indoor facilities

  • Line Lundbaek Barnkob
  • Paul Michael Petersen
  • Jens Peter Nielsen
  • Jette JakobsenEmail author
Original Paper


Vitamin D deficiency is a recognized problem in Europe; this can be minimized by fortifying a broader range of foods. Our aim was to investigate the potential for enhancing the vitamin D content of pork from pigs raised in indoor facilities, by exposing the pigs to UVB for a period just before slaughter. Three groups of six pigs were exposed to 0, 0.7 or 1 SED/day for 28 days. A fourth group was exposed to 2 SED; this treatment was not completed due to mild erythema. The highest increase of vitamin D3 was achieved with 1 SED; the vitamin D3 content in loin was 3.7 ng/g; more than a factor of 2 higher compared to previously reported results from studies using 2000 IU/kg feed, the maximum allowed level in Europe. This is the first time an increase in the vitamin D content of pork has been reported as a result of using artificial UVB exposure of slaughter pigs in indoor facilities. However, the maximum production of vitamin D was probably not reached as a linear relationship between UVB dose and vitamin D content was found; therefore, the UVB-lighting method described still calls for further investigation to realise its full potential to enhance vitamin D in pork.


Vitamin D UVB Pork Pigs 



We would like to acknowledge the staff at Rørrendegård (University of Copenhagen) for their commitment to take care of the pigs, Heidi Jahn and Tamaris Phipps (DTU Food) for their skillful performance of the analysis for vitamin D and fat, and Dennis Dan Corell (DTU Fotonik) for performing the UVB measurements.


A grant from the European Commission under its Seventh Framework Programme (ODIN; Grant agreement no. 613977) and the Technical University of Denmark funded the project. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.

Compliance with ethical standards

Conflict of interest

The authors’ declares that they have no conflict of interest.

Compliance with ethics requirements

The Animal Experiments Inspectorate, part of the Danish Veterinary Food and Administration, judged that the trial did not need a governmental approval. No ethics committee was involved as the pigs lived similar to pigs at a farm except that they were exposed to UVB light similar to a daily exposure of approximately 5–20 min summer sunshine in Denmark. The project plan was assessed and approved by a veterinarian at the Department of Experimental Medicine at University of Copenhagen (Number P16-414). The animals were overseen by keepers and veterinarians during the trial.

Supplementary material

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Supplementary material 1 (PDF 62 KB)
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Supplementary material 2 (PDF 64 KB)
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Supplementary material 3 (PDF 90 KB)
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Supplementary material 4 (PDF 28 KB)
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Supplementary material 5 (PDF 65 KB)


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Copyright information

© Springer-Verlag GmbH Germany, part of Springer Nature 2018

Authors and Affiliations

  • Line Lundbaek Barnkob
    • 1
  • Paul Michael Petersen
    • 2
  • Jens Peter Nielsen
    • 3
  • Jette Jakobsen
    • 1
    Email author
  1. 1.Research Group for Bioactives - Analysis and ApplicationNational Food Institute, Technical University of DenmarkKgs. LyngbyDenmark
  2. 2.Department of Photonics EngineeringTechnical University of DenmarkRoskildeDenmark
  3. 3.Division for Production, Nutrition and HealthUniversity of CopenhagenFrederiksberg CDenmark

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