Soil bacteria contribute to the taste and smell
FRANKFURT. Truffles, along with caviar, are among the most expensive foods in the world. Because they grow underground, people use trained dogs or pigs to find them. But the distinctive smell of truffles is not only of interest to gourmets. A group of German and French scientists under the direction of the Goethe University Frankfurt have discovered that the smell of white truffles is largely produced by soil bacteria which are trapped inside truffle fruiting bodies.
White truffles from the Piedmont region in Italy can reach 5,000 Euro per kilogram, and black truffles from the Périgord region in Southern France as much as 2,000 Euro per kilogram. Particularly large specimens even fetch prices of up to 50,000 Euro per kilogram at auctions. Connoisseurs search for the precious delicacies near hazelnut trees, oaks and some species of pine. This is because truffles grow in a symbiotic relationship with the trees. For scientists truffles are therefore a model organism to investigate how symbiosis evolved between plants and fungi.
Truffles are also useful to study fungal smell and flavour. Understanding how flavours are created is indeed very important to the food industry. Yeasts and bacteria which make cheese and wine have been researched in depth, but little is known about how the flavour of other organisms, including truffles, is created.
Over the past 10 years, researchers already suspected that micro-organisms trapped inside truffle fruiting bodies contributed to the flavour. "When the genome of the black Perigord truffle was mapped in 2010, we thought that the fungus had sufficient genes to create its flavour on its own", junior professor Richard Splivallo from the Institute for Molecular Life Sciences at the Goethe University explained.
The team made up of German and French scientists studied the white truffle Tuber borchii. It is native to Europe but has been recently introduced in New Zealand and Argentina. The researchers were able to show that bacteria produce a specific class of volatile cyclic sulphur compounds, which make up part of the distinctive truffle smell. Dogs and pigs are able to find truffles underground thanks to the slightly sulphuric smell.
"However, our results cannot be transferred to other types of truffles", Splivallo says, "because the compounds we investigated are only found in the white truffle Tuber borchii." For this reason, in the future they plan to study compounds which are found in the Périgord and Piermont truffles and are common to all types of truffles. "We don't just want to know which part of the truffle flavour is produced by bacteria. We are also interested in how the symbiosis between fungi and microorganisms has evolved and how this benefits both symbiotic partners."
Splivallo R, Deveau A, Valdez N, Kirchhoff N, Frey-Klett P, Karlovsky P. (2014). Bacteria associated with truffle-fruiting bodies contribute to truffle aroma. Environmental Microbiology. DOI: 10.1111/1462-2920.12521
Information: Junior-Prof. Richard Splivallo, Institute for Molecular Bio Sciences, Campus Riedberg, Tel.: 0049(0)69/ 798- 42193, Splivallo@bio.uni-frankfurt.de.
Long lost Roman fort discovered
FRANKFURT. In the course of an educational dig in Gernsheim in the Hessian Ried, archaeologists from Frankfurt University have discovered a long lost Roman fort: A troop unit made up out of approximately 500 soldiers (known as a cohort) was stationed there between 70/80 and 110/120 AD. Over the past weeks, the archaeologists found two V-shaped ditches, typical of this type of fort, and the post holes of a wooden defensive tower as well as other evidence from the time after the fort was abandoned.
An unusually large number of finds were made. This is because the Roman troops dismantled the fort and filled in the ditches when they left. In the process they disposed of a lot of waste, especially in the inner ditch. "A bonanza for us," according to Prof. Dr. Hans-Markus von Kaenel from the Goethe University Institute of Archaeology. "We filled box after box with shards of fine, coarse and transport ceramics; dating them will allow us to determine when the fort was abandoned with greater accuracy than was possible before".
Up until now, little was known about Roman Gernsheim, even though findings from the Roman era have been cropping up here since the 19th century. "Previously, the only thing that seemed certain based on the finds was that an important village-like settlement, or "vicus", must have been located here from the 1st to the 3rd century, comparable with similar villages which have already been shown to have existed in Groß-Gerau, Dieburg or Ladenburg", explained dig leader Dr. Thomas Maurer. He has been travelling from Frankfurt to South Hessia for years and has published his findings in a large publication about the North Hessian Ried during Roman imperial times.
"It was assumed", continued Maurer, "that this settlement had to have been based on a fort, since it was customary for the families of the soldiers to live outside the fort in a village-like settlement." "We really hit the jackpot with this excavation campaign", said a delighted Prof. Dr. Hans-Markus von Kaenel. "The results are a milestone in reconstructing the history of the Hessian Ried during Roman times." For almost 20 years now, von Kaenel has been studying this area with the help of his colleagues and students using surveys, digs, material processing and analyses. The results have been published in over 50 articles.
The Romans built the fort in Gernsheim in order to take control of large areas to the east of the Rhine in the seventh decade of the 1st century AD and to expand the traffic infrastructure from and to the centre of Mainz-Mogontiac. The fact that Gernsheim am Rhein was very important during Roman times is supported by its favourable location for travel: A road branches off from the Mainz – Ladenburg – Augsburg highway in the direction of the Main Limes. One can assume that a Rhine harbour existed as well, but this couldn't be verified during the course of this dig. "That was always unlikely on account of the chosen location", according to Maurer. Gernsheim continued to expand during the 20th century, and this expansion threatened to wipe out more and more of the archaeological traces. While the Roman remains were mostly still hidden under fields and gardens in the year 1900, they were gradually built over and thus lost to methodical archaeological research. The last plot of any measurable size where it might still be possible to make findings from the Roman era was an area in the south west of the city between the B44 and the River Winkelbach. But in 1971 the excavators moved in here as well. Maurer added: "At the time, a few volunteers from the Heritage Conservation Society were barely able to save a few Roman finds.
On August 4 of this year, the annual educational dig run by the Goethe University Institute of Archaeology began on one of the few remaining properties which had not been built on; a double lot at Nibelungenstraße 10-12. "According to my maps of those Gernsheim sites which could be located, we are at the far western edge of the area in which the finds are concentrated, right at the edge of the lower terrace, since the nearby River Winkelbach flows into the Rhine basin from here", explained dig leader Maurer. Isolated Roman finds were made on almost all neighbouring properties during the 1970s and 1980s. "Thus the site seemed to be a worthwhile location for a dig, which turned out to be very much the case."
Over the past five weeks, 15 students of the "Archaeology and History of the Roman Provinces" course carefully stripped away the soil, mapped and documented the finds, and recovered and packaged them by type. The work was supported by Frankfurt archaeologists from the Hessian State Office for the Preservation of Historical Monuments (Hessen ARCHÄOLOGIE, Darmstadt branch) and by the Art and History Society of Schöfferstadt Gernsheim. Some members of this society, which also operates the local museum, supported the dig team on a daily basis. The documentation and the findings from this excavation campaign form the basis for a thesis at the University, work on which will start in the winter semester.
Pictures can be downloaded from: www.muk.uni-frankfurt.de/51885456
Information: Dr. Thomas Maurer, Institute of Archaeology, West End Campus, Phone: 0177-5672114, firstname.lastname@example.org
The authority as to the interpretation of the Islamic faith must not be left to militant extremists
FRANKFURT. At the start of the congress 'Horizons of Islamic Theology' taking place at the Goethe University in Frankfurt, representatives of the departments for Islamic Theological Studies in Germany have published a statement on the current political developments in the Middle East They state that the authority in terms of interpreting the Islamic faith must not be left to militant extremists, who are also increasingly finding followers amongst young people in Europe, but must come from the centre of German society -- including the universities.
They express their grave concern about the brutal methods being employed by followers of Islamic State. The signatories to the statement believe the causes of such a violence-centred understanding of the religion lie in the desperate socio-political situation in the Middle East and other parts of the world.
Below is the actual wording of the statement, which has now also been signed by many more academics.
“We are deeply shocked and appalled by the current political developments in the Middle East and by the terror to which the so-called “Islamic State” (IS) is subjecting civilians and prisoners of all religions and ethnicities. The outrageous violence displayed by the followers of the IS violates all principles of humanity and civilisational norms; principles which Islam itself has shared over centuries and to which it has significantly contributed. We strongly reject and condemn interpretations of Islam that pervert this religion into an anachronistic ideology of hate and violence.
Given the increasing number of young people in Europe who are aligning themselves with the ideology of the IS and similar extremist formations, we are, as representatives of Islamic theological studies, fully aware of the responsibility and the necessity to counter such interpretations of Islam by referring to the Islamic traditions themselves. The authority, in matters of interpretation of Islam, has to be based in the societal mainstream, including the universities, and must not be ceded to extremists and violent perpetrators.
In our university work and beyond, we are committed to an interpretation of Islam that is based on the ideas of humanity and non-violence, on appreciation of pluralism and on respect towards human beings regardless of their religious and other affiliations.
The current conflicts in the Middle East and in other parts of the world clearly show how quickly violence-centered interpretations of religion can emerge under desolate sociopolitical conditions.
By contrast, in the free democratic societies of Europe we see a chance to relate to the rich intellectual and religious history of Islam in a reflective way and to engage positively with other perspectives, including the critical ones. Students of Islamic theological studies in Germany should utilize their religious resources as a means to creatively shape a common future with other members of society. Muslims are an integral part of the German society, and recognition of this fact is an important stage in this endeavour. At the same time, the past and recent Islamophobic and anti-Muslim assaults have to be recognized as obstacles along this way.
It is only through a reflective approach to the Islamic teaching and practice under conditions of freedom that the production of Islamic knowledge and norms can be disassociated from the contexts of crises and political repressions. And it is only through such an approach that Islam will be able to provide productive answers to the challenges of the global coexistence. The free proliferation of academic knowledge at the universities is an important precondition for this process.”
Prof. Dr. Bekim Agai, Director of the Institute for the Studies of the Culture and Religion of Islam, Goethe University Frankfurt am Main
Prof. Dr. Maha El-Kaisy Friemuth, Director of the Department of Islamic Religious Studies, Friedrich Alexander University Erlangen-Nürnberg
Prof. Dr. Mouhanad Khorchide, Director of the Center for Islamic Theology, University of Münster
Prof. Dr. Yasar Sarikaya, Professor for Islamic Theology and its Didactics, Justus Liebig University Gießen
Prof. Dr. Erdal Toprakyaran, Director of the Center for Islamic Theology, Eberhard Karls University Tübingen
Prof. Dr. Bülent Ucar, Director of the Institute for Islamic Theology, University Osnabrück
You can sign the statement by sending your name and your institutional affiliation to: email@example.com
Information: Tim Sievers, B.A., Institute for the Study of Islamic Culture and Religion, Dept. of Linguistics and Cultural Studies, Tel. +49 (0)69-798-32767; firstname.lastname@example.org