The University of Salamanca and D.O.P Guijuelo study how to differentiate the Iberian ham with the Carbon 13 test.

They have been working for a year and a half in a scientific project based on the Carbon 13 test in order to distinguish true Iberian ham from others which are rich in oleic acid from feedstuffs. The aim of the project is to eliminate those hams that try to imitate the taste of Iberian acorn ham.

The key is the oleic acid, a type of fat that is produced by acorns. This gives the characteristic ham flavour and it can be even got if the Iberian pig is only fed on soybean or sunflower although the pig has hot eaten the acorn, explained the Secretary of the Denomination of Origin Guijuelo.

The research project was directed by Professor Clemente recio through the Department of Chemistry, University of Salamanca and the Technology Institute of Guijuelo Meat. For a year and a half they have been analysing a total of 26 Iberian pig farms located in the provinces of Salamanca, Cáceres, Badajoz, Seville and Córdoba.

Firstly, the Iberian pig is considered acorn if laboratory test results showed an 54% of oleic acid. This analysis is made with pork bacon which is at the back of the animal, next to the ham. The problem is that oleic acid not only comes from the acorn, but it can also be achieved with soybeans or oilseeds such as sunflower. To combat this potencial fraud, the research project has focused on a mass spectrometry technique that allows, through the technique of carbon 13, to differentiate whether the oleic acid comes from the acorn or from feedstuffs made with soy or sunflower.

According to D.O.P Guijuelo, this technique is similar to that of carbon 14, which is used to determine the age of prehistoric animal remains. The research achievement is to improve the quality of Iberian acorn ham. Last year, about 40% of Iberian acorn hams were rejected ”  for not eating enough acorns” as it was informned by the Denomination of Guijuelo.