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Tuesday, December 28, 2010

Tomato

Tomato

The tomato is a plant in the Solanaceae or nightshade family. The taxonomic name is eitherSolanum lycopersicum or Lycopersicon esculentum depending on the reference. Originating in South and Central America, the tomato is now grown world-wide for its brightly coloured (usually red, from the pigment lycopene) edible fruits. The word tomato derives from Náhuatltomatl 
Contents 

Pre-historytomatoes-red.jpg

The tomato is believed to have been first cultivated in ancient Peru, where several wild species of green tomatoes still grow. Then about three thousand years ago it was brought to Mexico. It is an offshoot of the Mexican lineage L. esculentum cerasiforme which is thought to be the direct ancestor of the modern tomato. The pottery of ancient Peruvian city-states do not appear to mention the tomato, this has led some botanists to conclude that the cultivation of the tomato was done in Mexico. However this is not conclusive as many other fruits in continuous cultivation in Peru are not present in the pottery. Also much horticultural knowledge was lost after the arrival of Europeans, and the Christian Church had a policy of burning all pagan books and quartering their keepers.

Early history


In the 16th and 17th centuries, many Europeans believed tomatoes were poisonous because of the plant's relationship to nightshade and tobacco, although they were grown as garden ornamentals.
The first traces of use of tomato as food date back to South Europe in the first half of the 18th century. Only in the second half of the 19th century cultivation of the tomato as food begins to be widespread, mainly in southern Italy and in France.
Vincenzo Corrado, a cook in the Neapolitan court, describes recipes with tomatoes in the bookIl cuoco galante, first edition 1773, adding more recipes with tomatoes in the 1819 edition.
In 1809, Nicolas Appert, a chef from Paris, published L'art de conserver le substances alimentaires d'origine animale et végétale pour plusieurs années, a book on food conservation where he deals also with preserving tomato.
Thomas Jefferson was a pioneer in growing tomatoes, beginning in 1809. He grew large ribbed "Spanish" tomatoes. Jefferson's daughters left numerous recipes that involved tomatoes, including gumbo soups, cayenne-spiced tomato soup, green tomato pickles, tomato preserves, and tomato omelettes. Tomatoes were purchased in 1806 for Presidential dinners. Randolph'sThe Virginia Housewife has seventeen recipes for tomatoes, including gazpacho, gumbo, and catsup. In an 1824 speech before the Albemarle Agricultural Society, Jefferson's son-in-law, Thomas Mann Randolph discussed the transformation of Virginia farming due to the introduction of new crops. He mentioned how tomatoes were virtually unknown ten years earlier, but by 1824 everyone was eating them because they believed they kept one's blood pure in the heat of summer."[1]
The following story is widely cited, but there are doubts by many historians that it ever happened. Some lingering doubts about the safety of the tomato in the United States were largely put to rest in 1820, when Colonel Robert Gibbon Johnson announced that at noon onSeptember 28, he would eat a basket of tomatoes in front of the Salem, New Jerseycourthouse. Reportedly, a crowd of more than 2,000 persons gathered in front of the courthouse to watch the poor man die after eating the poisonous fruits, and were shocked when he lived.

Modern uses of tomatoes

Tomatoes are now eaten freely in Europe as well as in the rest of the world; in fact, periodically since their exoneration, they have been esteemed as a purported aphrodisiac. Today, their consumption is believed to benefit the heart.
Lycopene, one of nature's most powerful antioxidants, is present in tomatoes and has been found to be beneficial in preventing prostate cancer, among other things.
Botanically a berry, the tomato is generally thought of and used as a vegetable: it's more likely to be part of a sauce or a salad than eaten whole as a snack, let alone as part of a dessert (though, depending on the variety, they can be quite sweet, especially roasted).
Tomatoes are used extensively in Mediterranean and Middle Eastern cuisines, especially Italianones. The tomato has an acidic property that is used to bring out other flavors. This same acidity makes tomatoes especially easy to preserve in home canning as tomato sauce or paste.Tomato juice is often canned and sold as a beverage. Unripe green tomatoes can also be used to make salsa, or they can be batter-dipped and fried.
The town of Buñol, Spain annually celebrates La Tomatina, a festival centered on an enormous tomato fight. Tomatoes are also a popular "non-lethal" throwing weapon in mass protests, and there is a common tradition of throwing rotten tomatoes at bad actors or singers on a stage.

Controversies


Fruit or vegetable?

Botanically speaking a tomato is the ovary, together with its seeds, of a flowering plant. This would mean that technically it would be considered a fruit. However, speaking from a culinary perspective the tomato is typically served as or part of a main course of a meal meaning that it would be considered a vegetable. This argument has lead to actual legal implications in the United States. In 1887, U.S. tariff laws which imposed a duty on vegetables but not on fruits caused the tomato's status to become a matter of legal importance. The U.S. Supreme Courtsettled this controversy in 1893, declaring that the tomato is a vegetable, along withcucumberssquashesbeans, and peas, using the popular definition which classifies vegetables by use: they are generally served with dinner and not dessert. The case is known as Nix v. Hedden
In concordance with this classification, the tomato is the state vegetable of New Jersey

The pronunciation conundrum

In some English speaking countries, the pronunciation of tomato is in dispute: it can either be pronounced to-MAY-to or to-MAH-to. The difference is inherent in the dialects: British Englishspeakers typically favor to-MAH-to, while American English speakers have a tendency to say to-MAY-to. The word's multiple pronunciations were immortalized in song in Gershwin's 1937 song,Let's Call the Whole Thing Off (You say to-may-to and I say to-mah-to / you say po-tay-to and I say po-tah-to), and have become a symbol for nitpicking pronunciation disputes. In this capacity it has even become an American slang term: saying "to-may-to, to-mah-to" when presented with two choices can mean "what's the big deal, there's no real difference."

Proper storage

Many people believe that tomatoes should be stored refrigerated. This actually destroys the flavor and texture. Ideally tomatoes should be stored between 55–65°F (13–18°C) at 80–95% relative humidity.

Picking and ripening

Tomatoes sold in American grocery stores are often picked unripe, and ripened in storage withethylene. Ethylene is the plant hormone produced by many fruits and acts as the cue to begin the ripening process. These tend to keep longer — but have poorer flavor and a mealier, starchier texture than tomatoes ripened on the plant. They may be recognized by their color, which is more pink or orange than the ripe tomato's deep red.
Recently, stores have begun selling "tomatoes on the vine" which are ripened still connected to a piece of vine. These tend to be much more flavorful (at a price premium) than artificially-ripened tomatoes, but still may not be the equal of local garden produce.
Also relatively recently, slow-ripening varieties of tomato have been developed by crossing a non-ripening variety with ordinary tomato varieties. Varieties were selected whose fruits have a long shelf life and at least reasonable flavor

Bananas Are Radioactive

Kevin Rosseel, morguefile.comHomework Helpers: Chemistry
Did you know bananas are slightly radioactive? Bananas contain high levels of potassium. Radioactive K-40 has an isotopic abundance of 0.01% and a half-life of 1.25 billion years. The average banana contains around 450 mg of potassium and will experience about 14 decays each second. It's not something you need to worry about, since 0.01% of the potassium already in your body is K-40, plus the element is essential for proper nutrition. If you have a banana for your lunch you aren't going to set off a Geiger counter. If you carry a produce truck full of them, then you might have a noticeable radiation signature. The same is true if you are carrying a lot of potatoes or potassium fertilizer.

Friday, December 3, 2010

H2O

Water is, in fact, a chemical. Its chemical formula is H2O (or, less 
commonly, HOH), which is what this website is named after. H2O is 
also one of the most well-known chemical formulas. When properly 
written, the "2" after the H is written in subscript (as you can see in the 
banner above), but due to formatting restrictions it will simply be 
written as "H2O" on this website.

What does H2O mean? Each water molecule is made of two hydrogen 
atoms and one oxygen atom, thus there are two "H" atoms and one 
"O". The atoms are joined by covalent bonding, meaning that they 
share electrons (as opposed to ionic bonding, in which atoms 
completely transfer electrons). On the right is an image of water's 
molecular structure.

Water is the most abundant molecule on Earth. Approximately 70% of 
the Earth's surface is water. Water is also the only substance on Earth 
which naturally occurs in a solid, liquid and gas form.
The Celsius temperature scale is based on waters' freezing point (0 
degrees) and boiling point (100 degrees). Unlike most substances, 
water's solid from is less dense than its liquid form - this is why ice 
cubes will float in your drinks. Water is also capable of absorbing a lot 
of heat before its temperature increases; thus it is used in things such 
as a radiator coolant in cars.

Water has a high surface tension. This is why some bugs like water 
striders (of the Gerridae family) can walk on water - because they weigh 
less than the surface tension of the water. Due to the shape of a water 
molecule, molecules stick and clump together to form this high 
tension (the two lighter hydrogen atoms in the image on the right 
could attach to the oxygen atom of another water molecule, and so 
forth). That's why water comes together in the form of drops - if it wasn't 
for gravity water would attach together in a spherical shape.