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Smoke Taint
Smoke taint is a broad term for a set of smoke imparted compounds found in affected wines, constituting a wine fault. Increasing incidences of smoke tainted wines are an important issue, given the recent occurrences of wildfires or bushfires in wine grape producing regions during the growing seasons. Examples of wildfires resulting in smoke tainted wines include the fires in South Africa in late 2017, October 2017 Northern California wildfires, the 2019–20 Australian bushfire season, and the 2020 Glass Fire in Northern California. Whenever ambient smoke comes into contact with developing grapes on vines for a period of time, there is a risk that the grapes will carry smoke taint and impart this in wine made from them. The risk is higher with red wines, because their fermentation process includes the grape skins. Around 20-25 percent of people are estimated to not be able to taste the smokiness, possibly because of a lack of enzymes in their saliva. Causes Smoke taint occurs ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Smoke
Smoke is a suspension of airborne particulates and gases emitted when a material undergoes combustion or pyrolysis, together with the quantity of air that is entrained or otherwise mixed into the mass. It is commonly an unwanted by-product of fires (including stoves, candles, internal combustion engines, oil lamps, and fireplaces), but may also be used for pest control ( fumigation), communication ( smoke signals), defensive and offensive capabilities in the military (smoke screen), cooking, or smoking (tobacco, cannabis, etc.). It is used in rituals where incense, sage, or resin is burned to produce a smell for spiritual or magical purposes. It can also be a flavoring agent and preservative. Smoke inhalation is the primary cause of death in victims of indoor fires. The smoke kills by a combination of thermal damage, poisoning and pulmonary irritation caused by carbon monoxide, hydrogen cyanide and other combustion products. Smoke is an aerosol (or mist) of solid particl ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cresol
Cresols (also hydroxytoluene or cresylic acid) are a group of aromatic organic compounds. They are widely-occurring phenols (sometimes called ''phenolics'') which may be either natural or manufactured. They are also categorized as methylphenols. Cresols commonly occur as either solids or liquids because their melting points are generally close to room temperature. Like other types of phenols, they are slowly oxidized by exposure to air, and the resulting impurities often give the samples a yellow to brownish red tint. Cresols have an odor characteristic to that of other simple phenols, reminiscent to some of a "coal tar" smell. The name "cresol" is an adduct of phenol and their traditional source, creosote. Structure and production In its chemical structure, a molecule of cresol has a methyl group substituted onto the ring of phenol. There are three forms (isomers) of cresol: ''ortho''-cresol ( ''o''-cresol), ''meta''-cresol ( ''m''-cresol), and ''para''-cresol ( ''p''-cresol). ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tannin
Tannins (or tannoids) are a class of astringent, polyphenolic biomolecules that bind to and precipitate proteins and various other organic compounds including amino acids and alkaloids. The term ''tannin'' (from Anglo-Norman ''tanner'', from Medieval Latin ''tannāre'', from ''tannum'', oak bark) refers to the use of oak and other bark in tanning animal hides into leather. By extension, the term ''tannin'' is widely applied to any large polyphenolic compound containing sufficient hydroxyls and other suitable groups (such as carboxyls) to form strong complexes with various macromolecules. The tannin compounds are widely distributed in many species of plants, where they play a role in protection from predation (acting as pesticides) and might help in regulating plant growth. The astringency from the tannins is what causes the dry and puckery feeling in the mouth following the consumption of unripened fruit, red wine or tea. Likewise, the destruction or modification of t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Wine Smoke Research
Wine is an alcoholic drink typically made from fermented grapes. Yeast consumes the sugar in the grapes and converts it to ethanol and carbon dioxide, releasing heat in the process. Different varieties of grapes and strains of yeasts are major factors in different styles of wine. These differences result from the complex interactions between the biochemical development of the grape, the reactions involved in fermentation, the grape's growing environment (terroir), and the wine production process. Many countries enact legal appellations intended to define styles and qualities of wine. These typically restrict the geographical origin and permitted varieties of grapes, as well as other aspects of wine production. Wines not made from grapes involve fermentation of other crops including rice wine and other fruit wines such as plum, cherry, pomegranate, currant and elderberry. Wine has been produced for thousands of years. The earliest evidence of wine is from the Caucasus ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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 chlor ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Syringol
Syringol is the organic compound with the formula HO(CH3O)2C6H3. The molecule is a phenol, with methoxy groups in the flanking (2 and 6) positions. It is the symmetrically dimethylated derivative of pyrogallol. It is a colorless solid, although typical samples are brown owing to air-oxidized impurities. Together with guaiacol, syringol and its derivatives are produced by the pyrolysis of lignin. Specifically, syringol is derived from the thermal decomposition of the sinapyl alcohol component. As such, syringol is an important component of wood smoke. Syringyl/guaiacyl ratio Lignin, comprising a major fraction of biomass, is sometimes classified according to the syringyl component. Pyrolysis of lignin derived from sinapyl alcohol affords syringol. The conversion involves replacement of the propenyl alcohol substituent of the sinapyl alcohol by hydrogen. A high syringyl (or S) content is indicative of lignin from angiosperms. In contrast, pyrolysis of lignin from gymnosperms gi ... [...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)2SO2 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Wine
Wine is an alcoholic drink typically made from fermented grapes. Yeast consumes the sugar in the grapes and converts it to ethanol and carbon dioxide, releasing heat in the process. Different varieties of grapes and strains of yeasts are major factors in different styles of wine. These differences result from the complex interactions between the biochemical development of the grape, the reactions involved in fermentation, the grape's growing environment (terroir), and the wine production process. Many countries enact legal appellations intended to define styles and qualities of wine. These typically restrict the geographical origin and permitted varieties of grapes, as well as other aspects of wine production. Wines not made from grapes involve fermentation of other crops including rice wine and other fruit wines such as plum, cherry, pomegranate, currant and elderberry. Wine has been produced for thousands of years. The earliest evidence of wine is from the Caucasus ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Glycoside
In chemistry, a glycoside is a molecule in which a sugar is bound to another functional group via a glycosidic bond. Glycosides play numerous important roles in living organisms. Many plants store chemicals in the form of inactive glycosides. These can be activated by enzyme hydrolysis, which causes the sugar part to be broken off, making the chemical available for use. Many such plant glycosides are used as medications. Several species of ''Heliconius'' butterfly are capable of incorporating these plant compounds as a form of chemical defense against predators. In animals and humans, poisons are often bound to sugar molecules as part of their elimination from the body. In formal terms, a glycoside is any molecule in which a sugar group is bonded through its anomeric carbon to another group via a glycosidic bond. Glycosides can be linked by an O- (an ''O-glycoside''), N- (a ''glycosylamine''), S-(a ''thioglycoside''), or C- (a '' C-glycoside'') glycosidic bond. According to th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Phenols
In organic chemistry, phenols, sometimes called phenolics, are a class of chemical compounds consisting of one or more hydroxyl groups (— O H) bonded directly to an aromatic hydrocarbon group. The simplest is phenol, . Phenolic compounds are classified as simple phenols or polyphenols based on the number of phenol units in the molecule. Phenols are both synthesized industrially and produced by plants and microorganisms. Properties Acidity Phenols are more acidic than typical alcohols. The acidity of the hydroxyl group in phenols is commonly intermediate between that of aliphatic alcohols and carboxylic acids (their pKa is usually between 10 and 12). Deprotonation of a phenol forms a corresponding negative phenolate ion or phenoxide ion, and the corresponding salts are called phenolates or phenoxides (aryloxides according to the IUPAC Gold Book). Condensation with aldehydes and ketones Phenols are susceptible to Electrophilic aromatic substitutions. Condensation with formald ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
