Scientists have discovered why tomatoes are tasteless in the refrigerator
MOSCOW, October 18 - RIA Novosti . US scientists have uncovered the molecular genetic mechanisms of why tomatoes collected from the garden and eaten on the spot, much tastier tomatoes from the fridge or stores, according to an article published in the PNAS .
Cultivated tomato (Solanum lycopersicum) were first discovered and domesticated by the ancient South American Indians, where this culture spread to Central America and came to Europe with the conquistadors in the 16th century. It is believed that the seeds of this plant were brought to Spain by Christopher Columbus and Hernan Cortes. Today there are thousands of commercial and "home" tomato varieties.
Harry Klee (Harry Klee) from the University of Florida in Gainesville (USA) and his colleagues reflect on one of the major issues for all lovers of this fruit - why tomatoes lying a long time in the refrigerator or store-bought, have a less vivid and interesting taste than fresh tomatoes from the garden.
Four years ago, Klee and his colleagues have uncovered part of this mystery, discovering a "secret ingredient" in house tomatoes - a set of eight aromatic molecules and sugars, which gave them tomatoes taste good. Interestingly, most of these substances are not acted on the language of the people, and in their nose.
These materials, as shown by new experiences Klee team gradually disappear after being hit by tomatoes in the refrigerator, where they disappear for a reason, and a very interesting genetic reasons.
Comparing aromatics sets in tomato cells, have been in the fridge and had just plucked from the bush, the researchers noticed an unusual thing - it turned out that disappeared not only the "secret ingredient" the taste of tomatoes, but also changed the way was "packed" their DNA .
As explained scientists human genetic material and all other living creatures to separate the cell nucleus, including tomato, packaged in special-histone proteins, which hold the coiled DNA in place and influence the "readability" of individual genes.
This packaging, as shown by experiments Klee and his colleagues, irreversibly changes into tomato cells 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 "tomato" taste and smell, almost completely stops and can not be restored even if the tomato is transferred back to a warm room.
Interestingly, all the other taste qualities of tomatoes, including the content of sugars and acids in its pulp, do not change after being hit in the refrigerator, and remain the same. Accordingly, all the negative changes in taste occur only because the tomato loses natural "flavorings".
Why is this happening? Most likely, the observations show Klee and his colleagues, tomato inhibits the synthesis of the "secret ingredient" for the reason that in this way he is trying to guard against overly rapid water evaporation in the cold. In addition, the enzymes responsible for the assembly of taste and odor molecules, operate much more slowly at low temperatures, which may explain the rapid disappearance from the taste and tomato smell in refrigerator. The discovery of this fact, as the scientists hope, will help to create new varieties of tomatoes without losing the taste of the cold.
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