Posts Tagged ‘oxidation’
Study Questions Life of White Wine in Plastic Containers
Wednesday, June 9th, 2010Wine Chemistry in a Bottle: The Role of Oxygen
Monday, February 22nd, 2010I’ve been reading The Billionaire’s Vinegar recently, the story about wine unearthed allegedly owned by our third President, Thomas Jefferson. While I’m only half way through, this “mystery” revolves around the discovery and authenticity of wine bottles with the inscription “Th J” and the intense bidding wars for these prizes unleashed at auction. You can read my review on the book by clicking here. What caught my eye was a discussion about the roll that oxygen plays in the maturation or spoiling of wine, in this case, a wine allegedly two hundred year old. It caused me to pause, reminding me that basic chemistry is so vital to the quality of the end product that we enjoy.
Oxygen was discovered by Joseph Priestly in 1774 when upon burning Mercury Oxide, noted that an odorless gas allowed a candle flame to burn far longer than anticipated. In 1775, Priestly placed a mouse in a closed jar with oxygen and to his astonishment, it survived 30 minutes and was revived without incident. Oxygen is the third most abundant element in the universe after hydrogen and helium and constitutes just short of 21% of our atmosphere. There are two forms of the element that make life possible for all of us. One is diatomic oxygen (two atoms combined to form O2) and the other O3 or Ozone, a layer high up in the atmosphere that protects us down here from the hazards of ultra violet radiation. Ironically, Ozone is a pollutant at the surface and can be a component of smog.
Resveratrol, Compound du Jour: Facts and Fiction
Thursday, September 24th, 2009Resveratrol, it seems, just can’t seem to catch its breath. Whether the focus of still another research study on its potential health benefits (see archived articles: Wine and Inflammation, Radioprotective Effects of Wine, Alcohol Impact on Alzheimer’s in the Elderly, Wine Consumption in Males May Extend Life, Grape Seed Extracts May Suppress Leukemic Cells, Study Finds Heightened Risk of Breast Cancer With Wine, Resveratrol May Counteract Obesity and Resveratrol May Limit Damage Post Stroke) or advertised as a “cure all for what ails ya,” word of the compound seems to be everywhere. So what is resveratrol?
Resveratrol is what is known as a polyphenol found in, amongst other things, the skin of red grapes. Phenolic compounds, a type of antioxidant, are divided into flavinoids (those compounds that are responsible for the flavor and taste of grapes and other fruits such as tannins) and non flavinoids, of which resveratrol is a member. Resveratrol is also found in peanuts, mulberries, blueberries, cranberries, spruce, eucalyptus and various Chinese herbs. Now that I have bored you with some very basic chemistry, lets get into the facts.
Tannins: A Lesson In Wine Chemistry
Wednesday, July 22nd, 2009In order to understand the chemistry of wine, you must first understand that the basic building block for much of wine chemistry centers on the organic molecule called a “phenol.” In chemistry terms, “phenols” are a circular molecule of carbon and oxygen. That said, think of phenols as the basic building block upon which other phenol molecules (poly phenols) or other organic molecules are added to make larger molecules. Each one of these larger molecules interacts with other (organic and inorganic) molecules to produce other molecules to include acids, esters, aldehydes, and a whole range of the chemicals that make wine what is it. You can think of these molecules as the chemical components that make up wine. Remember, 80% of wine is hydrogen and oxygen molecules combined: H2O.
Tannins are astringent, bitter plant polyphenols that either break up or shrink proteins. The key words being “bitter,” “plant,” “polyphenols” that attack proteins. Our mouths are full of protein, so when you put a bitter, polyphenol, from a plant in your mouth, a chemical reaction takes place and the astringency from the tannins causes the dry and puckery feeling in the mouth.
Loading ...
Visit us on…