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Cork Taint
Cork taint is a broad term referring to a wine fault characterized by a set of undesirable smells or tastes found in a bottle of wine, especially spoilage that can only be detected after bottling, aging and opening. Though modern studies have shown that other factors can also be responsible for taint – including wooden barrels, storage conditions and the transport of corks and wine – the cork stopper is normally considered to be responsible, and a wine found to be tainted on opening is said to be corked or "corky". Cork taint can affect wines irrespective of price and quality level. The chief cause of cork taint is the presence of the chemical compounds 2,4,6-trichloroanisole (TCA) or 2,4,6-tribromoanisole (TBA) in the wine, which in many cases will have been transferred from the cork, but which also can have been transferred through the cork rather than from it. TCA is a compound which does not occur naturally. It is created when some fungi are treated with chlorin ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
2,4,6-Trichloroanisole
2,4,6-Trichloroanisole (TCA) is a chemical compound that is a chlorinated derivative of anisole. TCA is a fungal metabolite of 2,4,6-trichlorophenol, which is used as a fungicide. It can be found in minute traces on packaging materials stored in the presence of fiberboard treated with trichlorophenol. TCA has an unpleasant earthy, musty and moldy smell and is the chemical primarily responsible for cork taint in wines. TCA has also been implicated as a major component of the "Rio defect" in coffees from Central and South America, which refers to a taste described as medicinal, phenolic, or iodine-like. TCA is usually produced when naturally occurring airborne fungi and bacteria (usually ''Aspergillus'' sp., ''Penicillium'' sp., ''Actinomycetes'', ''Botrytis cinerea'', ''Rhizobium'' sp., or ''Streptomyces'') are presented with chlorinated phenolic compounds, which they then convert into chlorinated anisole derivatives. The chlorophenols can originate from various contaminants such ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fungus
A fungus ( : fungi or funguses) is any member of the group of eukaryotic organisms that includes microorganisms such as yeasts and molds, as well as the more familiar mushrooms. These organisms are classified as a kingdom, separately from the other eukaryotic kingdoms, which by one traditional classification include Plantae, Animalia, Protozoa, and Chromista. A characteristic that places fungi in a different kingdom from plants, bacteria, and some protists is chitin in their cell walls. Fungi, like animals, are heterotrophs; they acquire their food by absorbing dissolved molecules, typically by secreting digestive enzymes into their environment. Fungi do not photosynthesize. Growth is their means of mobility, except for spores (a few of which are flagellated), which may travel through the air or water. Fungi are the principal decomposers in ecological systems. These and other differences place fungi in a single group of related organisms, named the ''Eumycota'' (''tru ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Wine Spectator
''Wine Spectator'' is an American lifestyle magazine that focuses on wine and wine culture, and gives out ratings to certain types of wine. It publishes 15 issues per year with content that includes news, articles, profiles, and general entertainment pieces. Each issue also includes from 400 to more than 1,000 wine reviews, which consist of wine ratings and tasting notes. The publication also awards its 100 chosen top wineries each year with the ''Winery of the Year Awards''. ''Wine Spectator'', like most other major wine publications, rates wine on a 100-point scale. The magazine's policy also states that editors review wines in blind tastings. Wine Spectator's current critics include executive editor Thomas Mathews; editor-at-large Harvey Steiman; senior editors James Laube, Kim Marcus, Bruce Sanderson, Tim Fish, James Molesworth, Alison Napjus and MaryAnn Worobiec; associate editor Gillian Sciaretta and associate tasting coordinator Aleksandar Zecevic. Past critics include for ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Oct-1-en-3-one
Oct-1-en-3-one (CH2=CHC(=O)(CH2)4CH3), also known as 1-octen-3-one, is the odorant that is responsible for the typical "metallic" smell of metals and blood coming into contact with skin. Oct-1-en-3-one has a strong metallic mushroom-like odor with an odor detection threshold of 0.03–1.12 µg/m3 and it is the main compound responsible for the "smell of metal", followed by decanal (smell: orange skin, flowery) and nonanal (smell: tallowy, fruity). Oct-1-en-3-one is the degradative reduction product of the chemical reaction of skin lipid peroxides and Fe2+. Skin lipid peroxides are formed from skin lipid by oxidation, either enzymatically by lipoxygenases or by air oxygen. Oct-1-en-3-one is a ketone analog of the alkene 1-octene. Natural occurrences It is also produced by ''Uncinula necator ''Uncinula necator'' (syn. ''Erysiphe necator'') is a fungus that causes powdery mildew of grape. It is a common pathogen of Vitis species, including the wine grape, ''Vitis vinifera' ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Geosmin
Geosmin ( ) is an irregular sesquiterpenoid, produced from the universal sesquiterpene precursor farnesyl pyrophosphate (also known as farnesyl diphosphate), in a two-step -dependent reaction. Geosmin, along with the irregular monoterpene 2-methylisoborneol, together account for the majority of biologically-caused taste and odor outbreaks in drinking water worldwide. Geosmin has a distinct earthy or musty odor, which most people can easily smell. The geosmin odor detection threshold in humans is very low, ranging from 0.006 to 0.01 micrograms per liter in water. Geosmin is also responsible for the earthy taste of beetroots and a contributor to the strong scent (petrichor) that occurs in the air when rain falls after a spell of dry weather or when soil is disturbed. In chemical terms, geosmin is a bicyclic alcohol with formula , a derivative of decalin. Its name is derived from the Ancient Greek words (), meaning "earth", and (), meaning "smell". The word was coined in 196 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Guaiacol
Guaiacol () is an organic compound with the formula C6H4(OH)(OCH3). It is a phenolic compound containing an methoxy functional group. Guaiacol appears as a viscous colorless oil, although aged or impure samples are often yellowish. It occurs widely in nature and is a common product of the pyrolysis of wood. Occurrence Guaiacol is usually derived from guaiacum or wood creosote. It is produced by a variety of plants. It is also found in essential oils from celery seeds, tobacco leaves, orange leaves, and lemon peels. The pure substance is colorless, but samples become yellow upon exposure to air and light. The compound is present in wood smoke, resulting from the pyrolysis of lignin. The compound contributes to the flavor of many substances such as whiskey and roasted coffee. Preparation The compound was first isolated by Otto Unverdorben in 1826. Guaiacol is produced by methylation of ''o''-catechol, for example using potash and dimethyl sulfate: :C6H4(OH)2 + (CH3O)2SO ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Peroxide
In chemistry, peroxides are a group of compounds with the structure , where R = any element. The group in a peroxide is called the peroxide group or peroxo group. The nomenclature is somewhat variable. The most common peroxide is hydrogen peroxide (), colloquially known simply as "peroxide". It is marketed as solutions in water at various concentrations. Many organic peroxides are known as well. In addition to hydrogen peroxide, some other major classes of peroxides are: * Peroxy acids, the peroxy derivatives of many familiar acids, examples being peroxymonosulfuric acid and peracetic acid, and their salts, one example of which is potassium peroxydisulfate. * Main group peroxides, compounds with the linkage (E = main group element). * Metal peroxides, examples being barium peroxide (), sodium peroxide Sodium peroxide is an inorganic compound with the formula Na2O2. This yellowish solid is the product of sodium ignited in excess oxygen. It is a strong base. This ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sterilization (microbiology)
Sterilization refers to any process that removes, kills, or deactivates all forms of life (particularly microorganisms such as fungi, bacteria, spores, and unicellular eukaryotic organisms) and other biological agents such as prions present in or on a specific surface, object, or fluid. Sterilization can be achieved through various means, including heat, chemicals, irradiation, high pressure, and filtration. Sterilization is distinct from disinfection, sanitization, and pasteurization, in that those methods reduce rather than eliminate all forms of life and biological agents present. After sterilization, an object is referred to as being sterile or aseptic. Applications Foods One of the first steps toward modernized sterilization was made by Nicolas Appert, who discovered that application of heat over a suitable period slowed the decay of foods and various liquids, preserving them for safe consumption for a longer time than was typical. Canning of foods is an extension ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Chlorine
Chlorine is a chemical element with the symbol Cl and atomic number 17. The second-lightest of the halogens, it appears between fluorine and bromine in the periodic table and its properties are mostly intermediate between them. Chlorine is a yellow-green gas at room temperature. It is an extremely reactive element and a strong oxidising agent: among the elements, it has the highest electron affinity and the third-highest electronegativity on the revised Pauling scale, behind only oxygen and fluorine. Chlorine played an important role in the experiments conducted by medieval alchemists, which commonly involved the heating of chloride salts like ammonium chloride ( sal ammoniac) and sodium chloride (common salt), producing various chemical substances containing chlorine such as hydrogen chloride, mercury(II) chloride (corrosive sublimate), and hydrochloric acid (in the form of ). However, the nature of free chlorine gas as a separate substance was only recognised aroun ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Preservative
A preservative is a substance or a chemical that is added to products such as food products, beverages, pharmaceutical drugs, paints, biological samples, cosmetics, wood, and many other products to prevent decomposition by microbial growth or by undesirable chemical changes. In general, preservation is implemented in two modes, chemical and physical. Chemical preservation entails adding chemical compounds to the product. Physical preservation entails processes such as refrigeration or drying.Erich Lück and Gert-Wolfhard von Rymon Lipinski "Foods, 3. Food Additives" in ''Ullmann's Encyclopedia of Industrial Chemistry'', 2002, Wiley-VCH, Weinheim. Preservative food additives reduce the risk of foodborne infections, decrease microbial spoilage, and preserve fresh attributes and nutritional quality. Some physical techniques for food preservation include dehydration, UV-C radiation, freeze-drying, and refrigeration. Chemical preservation and physical preservation techniques are ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
