Showing papers by "Francisco J. Heredia published in 2010"
TL;DR: The importance of olive oil color and the applicable legislation and regulation are discussed, including sections devoted to the pigments accounting for the growing importance as likely health-promoting substances.
Abstract: The color of olive oils, and of foods in general, can influence consumer choices to a large extent and can be related to the processing treatments they have undergone. Olive oil color is due to 2 types of pigments, chlorophylls and carotenoids, which are attracting the attention of the scientific community due to the probable health benefits they can provide. Appropriate methodologies for the meaningful definition of the color of olive oil are therefore necessary for various reasons. In this review, we discuss the importance of olive oil color and the applicable legislation and regulation, including sections devoted to the pigments accounting for the growing importance as likely health-promoting substances. Furthermore, we review in depth the different approaches (visual and instrumental methods) used for color measurements in the last 50 y. Instrumental methods have been shown to be highly appropriate for objective assessments and also for the rapid determination of the pigments.
88 citations
TL;DR: In this paper, two different refrigerating methods (dry ice and cooling of grapes) have been assessed regarding the colour and the phenolic composition of the Syrah wines elaborated by applying pre-fermentative cold maceration.
68 citations
TL;DR: Evaluation of the copigmentation based on colorimetric parameters in the CIELAB color space showed that prefermentative cold macerated wines were richer in those compounds accounting directly for the color of red wine and those involved in anthocyanin stabilization throughCopigmentation reactions (phenols), which was in accordance with the higher copIGmentation degree and darker, more saturated and vivid bluish colors.
Abstract: The stabilization of red wine color by the copigmentation phenomenon is a crucial process that does not always proceed favorably under natural conditions during the first stages of vinification. The impact of the prefermentative cold maceration technique on the phenolic composition and magnitude of the copigmentation level of organic Tempranillo wines elaborated in a warm climate have been studied as an enological alternative to the traditional maceration for obtaining highly colored wines. Tristimulus colorimetry was applied to study the color of wines during vinification, and a high-performance liquid chromatography (HPLC) procedure was used for the analysis of phenolic compounds. Spectrophotometric and colorimetric analyses were also performed to evaluate the copigmentation level of the wines. Significant chemical and color differences were found depending on the maceration technique applied. Prefermentative cold macerated wines were richer in those compounds accounting directly for the color of red wi...
52 citations
TL;DR: In this paper, a study was conducted to gain insight into the influence of the chemical structure of carotenoids in the color of orange juices, which correlated the colorimetric information of commercially available OJ with their carotensoid content by means of multiple regressions.
44 citations
TL;DR: The anthocyanin-rich extract (ARE) of the fruit from Pourouma cecropiifolia, a tropical plant native to the Amazon region, showed moderate cytotoxicity toward different cancer cell lines when evaluated by MTT assays.
Abstract: The anthocyanin-rich extract (ARE) of the fruit from Pourouma cecropiifolia, a tropical plant native to the Amazon region, showed moderate cytotoxicity toward different cancer cell lines when evaluated by MTT assays. This extract was fractionated using Sephadex LH-20 chromatography to obtain three fractions (F1−F3), the composition of which was analyzed by HPLC-PDA and LC-ESI/MS. F1 was composed primarily of the monomeric anthocyanins delphinidin-3-O-β-glucopyranoside, cyanidin-3-O-β-glucopyranoside, and cyanidin-3-O-(6′′-malonyl)glucopyranoside. F2 contained the isomeric flavonols quercetin 3-O-α-rhamnopyranosyl-(1→6)-β-galactopyranoside and quercetin 3-O-α-rhamnopyranosyl-(1→6)-β-glucopyranoside, the structures of which were confirmed by 1H and 13C NMR. F3 contained polymeric pigments, which were analyzed using tandem ESI/MS with an ion trap-TOF. The structures of two proanthocyanidin and two flavanol-anthocyanin condensed pigments were suggested on the basis of their MSn fragmentation patterns. After c...
38 citations
TL;DR: In this paper, the effect of adding wine from Graciano cv. ([G]) on the color and anthocyanic composition of Tempranillo cv wine ([T]) has been studied.
22 citations
TL;DR: In this article, a simple experiment was carried out to ascertain whether large changes in this parameter can affect significantly their color, and they observed that the addition of citric acid to increase the acidity of the control by roughly 50% speeded up the isomerisations initially, although it did not lead to markedly appreciable colour changes at the end of the study.
Abstract: The colour of orange juices is one of the main factors related to their acceptability. Their colour is mainly due to carotenoids, with the particularity that the major ones, the epoxycarotenoids, can isomerise into differently coloured isomers in the presence of acid. Since acidity is one of the main characteristics of citrus, we have carried out a simple experiment to ascertain whether large changes in this parameter can affect significantly their colour. We observed that the addition of citric acid to increase the acidity of the control by roughly 50% speeded up the isomerisations initially, although it did not lead to markedly appreciable colour changes at the end of the study. These observations may be important from a food safety point of view and in relation to the consumers’ choices. In this regard, these preliminary findings could be important for food technologists and the citrus industry in general.
16 citations