Tannins origin

As regards the tannin origin by location, the areas of strong industrial production today are Brazil, South A ica, India, Zimbabwe, Tanzania for mimosa tannin Argentina for quebracho tannin Indonesia for mangrove and for cube Gambier tannins and Italy and Slovenia for chestnut tannin. Tha-e are many other small to very small producers a bit everywhere, for example, small pine tannin factories in Turkey and Chile, an oak tannin factory in Poland and a grape pip tannin factory in France. 

Tannin-containing woods also darken with ammonia, a process which is usefully employed in darkening oak furniture by fuming . Ammonia stains can originate from animal glue, amino-type adhesives and concrete additive sources, particularly where damp conditions exist. 

Internal treatment-related problems may take the form of organic material present in deposits of iron oxide corrosion debris and salt scales. The material typically is present as carbonized organic components and may originate from water treatment chemicals such as quebracho, wattle, pymgallol, or other tannin derivatives. Also, acrylates, starches, sulfonated lignins, and other sludge dispersants may be present. 

The family Sapindaceae consists of 140 genera and 1500 species of trees widespread in tropical and subtropical regions. Classic examples of Sapindaceae are the fruit trees Nephelium lappaceum L. and Litchi chinensis Sonn., which provide rambutan and litchi, respectively. Chemically Sapindaceae are well known to abound with saponins and tannins. An example of ornamental Sapindaceae is Koelreuteria paniculata L., or golden rain tree, cultivated in temperate regions. The berries of Sapindus saponaria L., were used as soap by South American Indians, hence the origin of the word Sapindus from sapo and Indus or the soap of the Indies. 

The optimized RPLC UV-Vis ESI MS method for all typical blue colourants (indi-goids, hematein, tannins, anthocyanins and selected flavonoids) was used for the identification of dyes extracted from a thread taken from an Italian tapestry of unknown origin from the collection of the National Museum in Warsaw (Poland). It was found that to obtain the red-blue colour of the fibre a mixture of dyestuffs was probably used. The presence of indigotin, tannic and ellagic acid (at m/z 301, NI), as well as carminic acid, suggested the use of indigo and cochineal. Reseda luteola could also have been used due to the presence of luteolin and apigenin. 

Thiolysis also proved useful for the analysis of derived tannins. Methylmethine-linked tannin-like compounds resulting from acetaldehyde-mediated condensation of flavanols (see Section 5.5.S.2) yielded several adducts when submitted to acid-catalyzed cleavage in the presence of ethanethiol, providing information on the position of linkages in the original ethyl-linked compounds. " Thiolysis of red wine extracts released benzylthioether derivatives of several anthocyanin-flavanol adducts, indicating that such structures were initially linked to proanthocyanidins. However, some of the flavonoid derivatives present in wine (e.g., flavanol-anthocyanins ) are resistant to thiolysis, while others (e.g., flavanol-ethyl anthocyanins) were only partly cleaved. Thiolysis, thus, appears as a rather simple, sensitive, and powerful tool for quantification and characterization of proanthocyanidins, but provides mostly qualitative data for their reaction products. 

The astringency of wine tannin fractions appears to be correlated to the content of flavanol units released after thiolysis regardless of their environment in the original mol-ecules. Anthocyanins contributed neither bitterness nor astringency. Whether incorporation of anthocyanin moieties in tannin-derived structures affects their interactions with proteins and taste properties remains to be investigated. 

In a trial on a Barbara wine subject to MOX at 1.7-2.5 mL/L/month for 45 days in 50-L tanks, the wines were found to be higher in smoothness 4-5 months after the end of the MOX process (Bosso et ah, 2000). In the trial on Cabernet Sauvignon wines subject to MOX at 5 mL/L/month for 7 months (Atanasova et ah, 2002), a polymeric fraction from a Toyopearl column was analyzed by thiolysis to determine the MDP. After 7 months, the MDP values were similar for the MOX (12.2 0.9) and control (12.6 0.3) wines, and both greater than the initial wine value of 10.1 0.4. On the other hand, it was noted that the total amount of tannins (by LC), originally 1434 50 mg/L, declined further in the MOX wines (1214 39 mg/L) compared to the control (1340 44 mg/L) after 7 months. 

Tin total residue obtained from 50 er. ui Ihe original tannin solution, and dried at 105" (, is also usn-rlniiied. On now ealeulating the residue lor 2110 ev. of tmuiin. -.011111011. and deducting this from tlx tolnl residue left from 11 u liinniu solution (j-euted with the aluminum oxide, tin result should show that 1 gm. of nlmuiuuni oxide absorbs I), It) to 0.50 gm. of tannin. 

Singleton and Esau (I) reviewed the methods for phenol analysis of wine. They pointed out that study would be greatly advanced if one could determine the total content of phenolic substances and express it in such a way that analysis of subclasses of phenols could be related to the original total and a balance sheet could be obtained. One could then say, for example, this wine has a total phenolic content of 1200 mg/liter calculated as gallic acid, and of that total, cinnamic acid derivatives account for 200 mg/liter, anthocyanins for 300 mg/liter, other small flavonoids for 200 mg/liter, and condensed tannins complete the total with 500 mg/liter of gallic acid equivalent. To accomplish this, the total phenol analysis not only must meet ordinary criteria of reproducibility and precision, but it also must be based on chemical relationships such that fractions determined separately can be converted to units of the total. Of course when clearcut fractionation can be accomplished by... 

Correlation of Structure with Source. Allochthonous-derived DOM (8) was isolated from the Suwannee River at its origin in the Okefe-nokee Swamp in southern Georgia. The fiilvic acid fraction, which is responsible for the black coloration of the water, was extensively characterized (9). Several average molecular models based on quantitative analytical data were presented in that report (10) to denote the mixture characteristics of fiilvic acid. One model, modified to depict biochemical sources and based on quantitative analytical data (10), is presented in Structure 1. Other models of Suwannee River fulvic acid (based on lignins, terpenoids, tannins, and flavonoid sources) were previously proposed (II). 

Folklore Kola is traditionally used in tonics for exhaustion and poor appetite. The tannins have an astringent effect in cases of diarrhoea. In the countries of origin the seed is ground as a condiment for food and chewed before meals to promote good digestion (Bown, 2003 British Herbal Medicine Association, 1983 Gruenwald et al., 2002 Tierra, 1998). 

Evaporation. 60 c.c. of the filtrate (corresponding with 50 c.c. of the tanning solution) are evaporated on a water-bath and the residue dried in a steam-oven and weighed this represents the non-tannins and is calculated as a percentage on the original substance. 

The tannin content of different raw materials varies considerably, according to the quality and origin, as is seen from the examples quoted in the following table (XXXVIII), which gives also the soluble non-tannins and the reducing sugars. 

A coloured acid extract precipitated by tannin is not obtained. Reduce Original fibre with Hydrosulphite B X. 

This complex tannin is formed during the aging process of red wine, whereby the catechin unit originates from the grapes, and the ellagitannin, in this case vescalagin, originates from the oak barrels. 

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