MOSCOW, 18 Jul – RIA Novosti. American scientists have uncovered molecular and genetic mechanisms of why tomatoes collected from the garden and eaten on the spot, much tastier tomatoes out of the fridge or the shops, according to a paper published in the journal PNAS.
Cultural tomato (Solanum lycopersicum) were first discovered and domesticated by the ancient South American Indians, where this culture has spread to Central America and came to Europe with the conquistadors in the 16th century. It is believed that the seeds of this plant was brought to Spain by Christopher Columbus or hernán cortés. Today there are thousands of commercial and “homemade” varieties of tomatoes.
Harry Klee (Harry Klee) at the University of Florida in Gainesville (USA) and his colleagues pondered one of the main issues for all lovers of this fruit is why tomatoes lying a long time in the fridge or store-bought, have less vivid and interesting flavor than fresh tomatoes from the garden.
Four years ago the Kli and his colleagues have solved part of this mystery, discovering “secret ingredient” in homemade tomato – a set of eight aromatic molecules and sugars that give tomatoes their flavor. Interestingly, most of these substances did not act on the language of the people, and in their nose.
These substances, as shown by the new team experiences Kli gradually disappear after being hit by tomatoes in the fridge, and they disappear, and a very interesting genetic reasons.
Comparing the sets of aromatic substances in the cells of the tomatoes have been in fridge and just plucked from the Bush, scientists have noticed the strange thing – it turned out that it’s not just “secret ingredient” taste of tomatoes, but also changed how I was “Packed” their DNA.
As the scientists explain, the genetic material of humans and all other creatures with the isolated cell nucleus, including tomato, Packed in special proteins-histones, which hold the folded DNA in place and do affect “readability” of individual genes.
This packing, as shown by experiments Kli and his colleagues, irreversible change in the cells of the tomatoes in if they are for a long time at temperatures below 12 degrees Celsius. As a result, the work of many genes involved in the synthesis of substances that give tomatoes the “tomato” taste and smell, almost completely stops and is not restored even when the tomato is transferred back to a warm room.
Interestingly, all the rest of the taste of the tomato, including the content of sugars and acids in the pulp do not change after hitting the fridge and remain the same. Accordingly, adverse changes in taste happen just because tomato is deprived of the natural “flavors”.
Why is this happening? Most likely, as observations show, the Kli and his colleagues, tomatoes suppresses the synthesis of this “secret ingredient” for the reason that in this way he is trying to defend against overly rapid water evaporation in the cold. In addition, the enzymes responsible for Assembly of molecules of smell and taste, working much more slowly at low temperatures, which may explain the rapid disappearance of taste and smell have a tomato in the fridge. The discovery of this fact, as scientists hope, will help create new varieties of tomatoes, do not lose the flavor of the cold.