Phenolic compounds maturity

Fresh peppers are excellent sources of vitamins A and C, as well as neutral and acidic phenolic compounds (Howard and others 2000). Levels of these can vary by genotype and maturity and are influenced by growing conditions and processing (Mejia and others 1988 Howard and others 1994 Lee and others 1995 Daood and others 1996 Simmone and others 1997 Osuna-Garcia and others 1998 Markus and others 1999 Howard and others 2000). Peppers have been reported to be rich in the provitamin A carotenoids (3-carotene, a-carotene, and (3-cryptoxanthin (Minguez-Mosquera and Hornero-Mendez 1994 Markus and others 1999), as well as xanthophylls (Davies and others 1970 Markus and others 1999). Bell peppers have been shown to exert low antioxidant activity (Al-Saikhan and others 1995 Cao and others 1996 Vinson and others 1998) or may even act as pro-oxidants (Gazzani and others 1998). 

Burda S, Oleszek W and Lee CY. 1990. Phenolic compounds and their changes in apples during maturation... 

Virgin olive oil contains considerable amounts of simple phenols that have a great effect on the stability/sensory and nutritional characteristics of the product. Some of the most representative are hydroxytyrosol (3,4-dihydroxyphenylethanol) and tyrosol (4-hydroxyphenylethanol) however, phenolic compounds are removed when the oil is refined (Tovar and others 2001). The phenolic content of virgin olive oil is influenced by the variety, location, degree of ripeness, and type of oil extraction procedure used, and that is why hydroxytyrosol can be considered as an indicator of maturation for olives (Esti and others 1998). Hydroxytyrosol concentrations are correlated with the stability of the oil, whereas those of tyrosol are not (Visioli and Galli 1998). 

Some flawless analytical methods do exist but more are needed. Quantitative extraction of all the phenolic compounds from skins and seeds is not possible however we have developed a standard, reproducible procedure. Using a solvent with physicochemical properties similar to wine, one performs three cold extractions followed by two warm ones. This gives an estimate of the total phenols and an idea of their solubilities—an important technological factor. Our work, done in 1969-1972 involved the two principal red varieties of Bordeaux (Merlot and Cabemet-Sauvignon) from two vineyards. One ( ) is a Grand Cru of the Medoc region characterized by fast maturation, and the other (SC) matures more slowly (46, 47). 

Table VIII. Phenolic Compounds in Grape Skins at Crop Maturity in Vineyard SC...

Amiot, M. T., Fleuriet, A., and Macheix, J. T. (1986). Importance and evolution of phenolic compounds in olive during growth and maturation. ]. Agric. Food Chem. 34, 823-826. Andrew, E. R., Bradbury, A., and Eades, R. G. (1958). Nudear magnetic resonance spectra from a crystal rotated at high speed. Nature 182,1659-1660. 

Wine treated with oak chips matures quickly, and more phenolic compounds can be extracted from wood chips than from oak staves and oak barrel aging (Alamo-Sanza etal. 2004). 

OC is a reddish-brown oily liquid obtained by extracting dried, ripe fruit of chili peppers, usually Capsicum annuum or Capsicum fruitescenes. The oleoresin is a mixture of many compounds. Its composition is variable and depends on factors such as maturity of the fruit and the environment in which the plants are grown, as well as the conditions of the extraction. More than 100 compounds have been identified in oleoresin capsicum. Among the branched-and straight-chain alkyl vanillylamides isolated from oleoresin capsicum, capsaicin is the major pungent component in many peppers, and it is particularly noted for its irritant properties. Depending on the variety of chili pepper, the oleoresin contains from 0.01% to 1.0% capsaicinoids on a dry mass basis. Other components of the oleoresin such as phenolic compounds, acids, and esters may also possess irritant properties. 

Color and Phenolic Compounds of Oak-Matured Wines as Affected by the Characteristics of the Barrel... 

Other studies have described similar results to those found in our research, that is, that ellagitannins are more abundant in French oak (26) and therefore, in wines matured in French oak barrels. So, the presence of ellagitannins enhances the color of wine and increases absorbance at 620 nm by fevoring anthocyanin-procyanidin type tannin condensations with acetaldehyde (purple pigments) and that foct also helps to explain the higher PVPP index values of wines fix)m new French oak barrels. They also prevent the development of brick-yellow color by preventing the oxidation of phenolic compounds (24). 

These phenolic compounds seem to play a role against the development of different types of cancer and cardiovascular diseases, because these compounds provide, at least in part, antioxidant capacity (AOC) [14], anti-inflammation [15,16], lipid profile modification [17,18] and antitumor effects [19-22]. Besides these beneficial properties of phenolic compounds in human health, these compounds are responsible of color, flavor, and smell in fruits and vegetables [23], and their contents are influenced by variety, crop type, environmental conditions, location, germination, maturity, processing, and storage [24-26]. Therefore, several procedmes have been developed for the analysis of this type of compound in the last few years. 

---