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Carmen M. Donangelo - One of the best experts on this subject based on the ideXlab platform.
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Effect of simultaneous consumption of soymilk and Coffee on the urinary excretion of isoflavones, chlorogenic acids and metabolites in healthy adults
Journal of Functional Foods, 2015Co-Authors: I. Felberg, Adriana Farah, Mariana C. Monteiro, Ronoel Luiz De Oliveira Godoy, Sidney Pacheco, Verônica Calado, Carmen M. DonangeloAbstract:Abstract The effect of the simultaneous ingestion of soymilk and Coffee on the urinary excretion of isoflavones (ISO) and chlorogenic acids (CGA) was investigated for the first time in humans. In a randomized crossover study, soy (79.7 µmol ISO), Coffee (561.2 µmol CGA) and soy–Coffee Beverage (79.7 µmol ISO and 561.2 µmol CGA) were ingested by adult subjects (n = 6) after overnight fasting. Urinary excretion of ISO aglycones and metabolites during 48 h after soy and soy–Coffee Beverages consumption was 22.0 ± 19.1 and 20.3 ± 9.4 µmol, respectively, with no difference between treatments. CGA and metabolite excretion during 24 h after Coffee and soy–Coffee Beverage consumption was 3.4 ± 1.2 and 3.1 ± 0.6 mmol, respectively. However, a 42% decrease in levels of CGA and primary metabolites and not of colonic metabolites was observed in urine after soy–Coffee Beverage consumption compared to plain Coffee, indicating that substances present in soymilk, most likely proteins, bind CGA reversibly, decreasing their absorption in the digestive tract.
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formulation of a soy Coffee Beverage by response surface methodology and internal preference mapping
Journal of Sensory Studies, 2010Co-Authors: Ilana Felberg, Rosires Deliza, Adriana Farah, Erônica Calado, Carmen M. DonangeloAbstract:ABSTRACT Coffee consumers (n = 60) tasted and rated samples of a new soy–Coffee Beverage made from instant Coffee, soymilk powder and sugar. Ingredient concentrations (independent variables) varied according to a 23central composite design for overall degree of acceptance. Data were analyzed by analysis of variance (ANOVA), least square difference and response surface methodology, followed by internal preference mapping (IPM) with cluster analysis. ANOVA from the consumers' acceptance data revealed that samples differed significantly (P ≤ 0.05). Although soymilk content did not influence significantly the consumers' acceptance in the tested range, IPM with cluster analysis indicated that at least part of the acceptance differences was based on the soy Beverage consumption habit. The final Beverage formulation was evaluated cold and hot for overall acceptability (9-point structured hedonic scale) by 112 Coffee consumers and the cold Beverage reached a good acceptability mean score (6.2) among the participants. PRACTICAL APPLICATIONS The consumption of soy products has been reported to reduce the risk of several diseases and a number of recent studies have found beneficial health properties attributed to Coffee. Considering the current consumer trend for healthier alternatives in food products, we decided to combine the health benefits of these two important Brazilian commodities in a functional Beverage. In order to optimize the formulation and maximize sensory acceptance, we performed consumers' tests using response surface methodology. Internal preference mapping and cluster analyses were also applied to provide information on the variability of the consumer individual opinions and segment them in groups of similar preference criteria.
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FORMULATION OF A SOY–Coffee Beverage BY RESPONSE SURFACE METHODOLOGY AND INTERNAL PREFERENCE MAPPING
Journal of Sensory Studies, 2010Co-Authors: Ilana Felberg, Rosires Deliza, Adriana Farah, Erônica Calado, Carmen M. DonangeloAbstract:ABSTRACT Coffee consumers (n = 60) tasted and rated samples of a new soy–Coffee Beverage made from instant Coffee, soymilk powder and sugar. Ingredient concentrations (independent variables) varied according to a 23central composite design for overall degree of acceptance. Data were analyzed by analysis of variance (ANOVA), least square difference and response surface methodology, followed by internal preference mapping (IPM) with cluster analysis. ANOVA from the consumers' acceptance data revealed that samples differed significantly (P ≤ 0.05). Although soymilk content did not influence significantly the consumers' acceptance in the tested range, IPM with cluster analysis indicated that at least part of the acceptance differences was based on the soy Beverage consumption habit. The final Beverage formulation was evaluated cold and hot for overall acceptability (9-point structured hedonic scale) by 112 Coffee consumers and the cold Beverage reached a good acceptability mean score (6.2) among the participants. PRACTICAL APPLICATIONS The consumption of soy products has been reported to reduce the risk of several diseases and a number of recent studies have found beneficial health properties attributed to Coffee. Considering the current consumer trend for healthier alternatives in food products, we decided to combine the health benefits of these two important Brazilian commodities in a functional Beverage. In order to optimize the formulation and maximize sensory acceptance, we performed consumers' tests using response surface methodology. Internal preference mapping and cluster analyses were also applied to provide information on the variability of the consumer individual opinions and segment them in groups of similar preference criteria.
Jian-min Yuan - One of the best experts on this subject based on the ideXlab platform.
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Associations between tea and Coffee Beverage consumption and the risk of lung cancer in the Singaporean Chinese population
European Journal of Nutrition, 2019Co-Authors: Wei Jie Seow, Renwei Wang, Jian-min YuanAbstract:Background Tea and Coffee are widely consumed Beverages. Tea flavonoids have been shown to inhibit lung tumorigenesis using in vitro and in vivo models. Conversely, Coffee contains complex mixtures of biochemically active compounds, some of which may have genotoxic and mutagenic properties. However, previous epidemiologic studies have shown inconsistent results on tea and Coffee in relation to lung cancer risk. Methods The Singapore Chinese Health Study is a population-based prospective cohort of 63,257 Singaporean Chinese men and women, with an average of 17.7 years of follow-up. Information on tea and Coffee consumption and other lifestyle factors was collected through in-person interviews at baseline. Multivariable Cox regression models were used to estimate hazard ratios (HRs) and 95% confidence intervals (CIs) for the associations with adjustment for potential confounders. Results There were 1486 incident lung cancer cases. Compared to non-daily Coffee drinkers, HRs (95% CIs) of lung cancer risk for those consuming one, two, and three or more cups of Coffee per day were 1.18 (1.02–1.36), 1.21 (1.05–1.40), and 1.32 (1.08–1.62) respectively ( P for trend = 0.0034). The highest category of black tea consumption (at least 2 cups per day) was inversely associated with risk of lung cancer [HR (95% CI) = 0.73 (0.53–0.99)], particularly among men [HR (95% CI) = 0.67 (0.47–0.95)], compared to less-than-weekly black tea drinkers, although the interaction by sex was not statistically significant. Conclusions Coffee Beverage consumption was associated with higher risk of developing lung cancer. On the other hand, black tea intake was associated with lower risk of lung cancer among men in our cohort, and further studies are needed to confirm this association.
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Associations between tea and Coffee Beverage consumption and the risk of lung cancer in the Singaporean Chinese population.
European journal of nutrition, 2019Co-Authors: Wei Jie Seow, Renwei Wang, Woon-puay Koh, Aizhen Jin, Jian-min YuanAbstract:Tea and Coffee are widely consumed Beverages. Tea flavonoids have been shown to inhibit lung tumorigenesis using in vitro and in vivo models. Conversely, Coffee contains complex mixtures of biochemically active compounds, some of which may have genotoxic and mutagenic properties. However, previous epidemiologic studies have shown inconsistent results on tea and Coffee in relation to lung cancer risk. The Singapore Chinese Health Study is a population-based prospective cohort of 63,257 Singaporean Chinese men and women, with an average of 17.7 years of follow-up. Information on tea and Coffee consumption and other lifestyle factors was collected through in-person interviews at baseline. Multivariable Cox regression models were used to estimate hazard ratios (HRs) and 95% confidence intervals (CIs) for the associations with adjustment for potential confounders. There were 1486 incident lung cancer cases. Compared to non-daily Coffee drinkers, HRs (95% CIs) of lung cancer risk for those consuming one, two, and three or more cups of Coffee per day were 1.18 (1.02–1.36), 1.21 (1.05–1.40), and 1.32 (1.08–1.62) respectively (P for trend = 0.0034). The highest category of black tea consumption (at least 2 cups per day) was inversely associated with risk of lung cancer [HR (95% CI) = 0.73 (0.53–0.99)], particularly among men [HR (95% CI) = 0.67 (0.47–0.95)], compared to less-than-weekly black tea drinkers, although the interaction by sex was not statistically significant. Coffee Beverage consumption was associated with higher risk of developing lung cancer. On the other hand, black tea intake was associated with lower risk of lung cancer among men in our cohort, and further studies are needed to confirm this association.
Adriana Farah - One of the best experts on this subject based on the ideXlab platform.
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Effect of simultaneous consumption of soymilk and Coffee on the urinary excretion of isoflavones, chlorogenic acids and metabolites in healthy adults
Journal of Functional Foods, 2015Co-Authors: I. Felberg, Adriana Farah, Mariana C. Monteiro, Ronoel Luiz De Oliveira Godoy, Sidney Pacheco, Verônica Calado, Carmen M. DonangeloAbstract:Abstract The effect of the simultaneous ingestion of soymilk and Coffee on the urinary excretion of isoflavones (ISO) and chlorogenic acids (CGA) was investigated for the first time in humans. In a randomized crossover study, soy (79.7 µmol ISO), Coffee (561.2 µmol CGA) and soy–Coffee Beverage (79.7 µmol ISO and 561.2 µmol CGA) were ingested by adult subjects (n = 6) after overnight fasting. Urinary excretion of ISO aglycones and metabolites during 48 h after soy and soy–Coffee Beverages consumption was 22.0 ± 19.1 and 20.3 ± 9.4 µmol, respectively, with no difference between treatments. CGA and metabolite excretion during 24 h after Coffee and soy–Coffee Beverage consumption was 3.4 ± 1.2 and 3.1 ± 0.6 mmol, respectively. However, a 42% decrease in levels of CGA and primary metabolites and not of colonic metabolites was observed in urine after soy–Coffee Beverage consumption compared to plain Coffee, indicating that substances present in soymilk, most likely proteins, bind CGA reversibly, decreasing their absorption in the digestive tract.
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formulation of a soy Coffee Beverage by response surface methodology and internal preference mapping
Journal of Sensory Studies, 2010Co-Authors: Ilana Felberg, Rosires Deliza, Adriana Farah, Erônica Calado, Carmen M. DonangeloAbstract:ABSTRACT Coffee consumers (n = 60) tasted and rated samples of a new soy–Coffee Beverage made from instant Coffee, soymilk powder and sugar. Ingredient concentrations (independent variables) varied according to a 23central composite design for overall degree of acceptance. Data were analyzed by analysis of variance (ANOVA), least square difference and response surface methodology, followed by internal preference mapping (IPM) with cluster analysis. ANOVA from the consumers' acceptance data revealed that samples differed significantly (P ≤ 0.05). Although soymilk content did not influence significantly the consumers' acceptance in the tested range, IPM with cluster analysis indicated that at least part of the acceptance differences was based on the soy Beverage consumption habit. The final Beverage formulation was evaluated cold and hot for overall acceptability (9-point structured hedonic scale) by 112 Coffee consumers and the cold Beverage reached a good acceptability mean score (6.2) among the participants. PRACTICAL APPLICATIONS The consumption of soy products has been reported to reduce the risk of several diseases and a number of recent studies have found beneficial health properties attributed to Coffee. Considering the current consumer trend for healthier alternatives in food products, we decided to combine the health benefits of these two important Brazilian commodities in a functional Beverage. In order to optimize the formulation and maximize sensory acceptance, we performed consumers' tests using response surface methodology. Internal preference mapping and cluster analyses were also applied to provide information on the variability of the consumer individual opinions and segment them in groups of similar preference criteria.
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species roasting degree and decaffeination influence the antibacterial activity of Coffee against streptococcus mutans
Food Chemistry, 2010Co-Authors: Andrea Goncalves Antonio, Renata Simoes Moraes, Daniel Perrone, Lucianne Cople Maia, Katia Regina Netto Dos Santos, Natalia Lopes Pontes Iorio, Adriana FarahAbstract:Coffee Beverage has been associated with antibacterial activity against Streptococcus mutans, a cariogenic bacterium. This study aimed at identifying natural compounds in Coffee that contribute to such activity and investigate the influence of species, roasting and decaffeination on it. Coffee chemical compounds and aqueous extracts of green and roasted regular and decaffeinated Coffea arabica and Coffea canephora beans were tested. MIC, biofilm inhibition and biofilm reduction results were correlated with the concentration of Coffee compounds in the extracts. 5-Caffeoylquinic acid, trigonelline and caffeic acid solutions showed bacteriostatic activity (MIC = 0.8 mg/mL). Lighter and regular extracts showed higher inhibitory activity than darker and decaffeinated extracts, with an inverse correlation between bacterial colony-forming units and roasting degree. Only regular C. canephora extracts showed biofilm formation inhibition. The joint effect of chlorogenic acids, trigonelline and caffeine or other compounds removed by decaffeination seems to be one of the causes for Coffee antibacterial activity against S. mutans.
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FORMULATION OF A SOY–Coffee Beverage BY RESPONSE SURFACE METHODOLOGY AND INTERNAL PREFERENCE MAPPING
Journal of Sensory Studies, 2010Co-Authors: Ilana Felberg, Rosires Deliza, Adriana Farah, Erônica Calado, Carmen M. DonangeloAbstract:ABSTRACT Coffee consumers (n = 60) tasted and rated samples of a new soy–Coffee Beverage made from instant Coffee, soymilk powder and sugar. Ingredient concentrations (independent variables) varied according to a 23central composite design for overall degree of acceptance. Data were analyzed by analysis of variance (ANOVA), least square difference and response surface methodology, followed by internal preference mapping (IPM) with cluster analysis. ANOVA from the consumers' acceptance data revealed that samples differed significantly (P ≤ 0.05). Although soymilk content did not influence significantly the consumers' acceptance in the tested range, IPM with cluster analysis indicated that at least part of the acceptance differences was based on the soy Beverage consumption habit. The final Beverage formulation was evaluated cold and hot for overall acceptability (9-point structured hedonic scale) by 112 Coffee consumers and the cold Beverage reached a good acceptability mean score (6.2) among the participants. PRACTICAL APPLICATIONS The consumption of soy products has been reported to reduce the risk of several diseases and a number of recent studies have found beneficial health properties attributed to Coffee. Considering the current consumer trend for healthier alternatives in food products, we decided to combine the health benefits of these two important Brazilian commodities in a functional Beverage. In order to optimize the formulation and maximize sensory acceptance, we performed consumers' tests using response surface methodology. Internal preference mapping and cluster analyses were also applied to provide information on the variability of the consumer individual opinions and segment them in groups of similar preference criteria.
Wei Jie Seow - One of the best experts on this subject based on the ideXlab platform.
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Associations between tea and Coffee Beverage consumption and the risk of lung cancer in the Singaporean Chinese population
European Journal of Nutrition, 2019Co-Authors: Wei Jie Seow, Renwei Wang, Jian-min YuanAbstract:Background Tea and Coffee are widely consumed Beverages. Tea flavonoids have been shown to inhibit lung tumorigenesis using in vitro and in vivo models. Conversely, Coffee contains complex mixtures of biochemically active compounds, some of which may have genotoxic and mutagenic properties. However, previous epidemiologic studies have shown inconsistent results on tea and Coffee in relation to lung cancer risk. Methods The Singapore Chinese Health Study is a population-based prospective cohort of 63,257 Singaporean Chinese men and women, with an average of 17.7 years of follow-up. Information on tea and Coffee consumption and other lifestyle factors was collected through in-person interviews at baseline. Multivariable Cox regression models were used to estimate hazard ratios (HRs) and 95% confidence intervals (CIs) for the associations with adjustment for potential confounders. Results There were 1486 incident lung cancer cases. Compared to non-daily Coffee drinkers, HRs (95% CIs) of lung cancer risk for those consuming one, two, and three or more cups of Coffee per day were 1.18 (1.02–1.36), 1.21 (1.05–1.40), and 1.32 (1.08–1.62) respectively ( P for trend = 0.0034). The highest category of black tea consumption (at least 2 cups per day) was inversely associated with risk of lung cancer [HR (95% CI) = 0.73 (0.53–0.99)], particularly among men [HR (95% CI) = 0.67 (0.47–0.95)], compared to less-than-weekly black tea drinkers, although the interaction by sex was not statistically significant. Conclusions Coffee Beverage consumption was associated with higher risk of developing lung cancer. On the other hand, black tea intake was associated with lower risk of lung cancer among men in our cohort, and further studies are needed to confirm this association.
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Associations between tea and Coffee Beverage consumption and the risk of lung cancer in the Singaporean Chinese population.
European journal of nutrition, 2019Co-Authors: Wei Jie Seow, Renwei Wang, Woon-puay Koh, Aizhen Jin, Jian-min YuanAbstract:Tea and Coffee are widely consumed Beverages. Tea flavonoids have been shown to inhibit lung tumorigenesis using in vitro and in vivo models. Conversely, Coffee contains complex mixtures of biochemically active compounds, some of which may have genotoxic and mutagenic properties. However, previous epidemiologic studies have shown inconsistent results on tea and Coffee in relation to lung cancer risk. The Singapore Chinese Health Study is a population-based prospective cohort of 63,257 Singaporean Chinese men and women, with an average of 17.7 years of follow-up. Information on tea and Coffee consumption and other lifestyle factors was collected through in-person interviews at baseline. Multivariable Cox regression models were used to estimate hazard ratios (HRs) and 95% confidence intervals (CIs) for the associations with adjustment for potential confounders. There were 1486 incident lung cancer cases. Compared to non-daily Coffee drinkers, HRs (95% CIs) of lung cancer risk for those consuming one, two, and three or more cups of Coffee per day were 1.18 (1.02–1.36), 1.21 (1.05–1.40), and 1.32 (1.08–1.62) respectively (P for trend = 0.0034). The highest category of black tea consumption (at least 2 cups per day) was inversely associated with risk of lung cancer [HR (95% CI) = 0.73 (0.53–0.99)], particularly among men [HR (95% CI) = 0.67 (0.47–0.95)], compared to less-than-weekly black tea drinkers, although the interaction by sex was not statistically significant. Coffee Beverage consumption was associated with higher risk of developing lung cancer. On the other hand, black tea intake was associated with lower risk of lung cancer among men in our cohort, and further studies are needed to confirm this association.
Thomas Hofmann - One of the best experts on this subject based on the ideXlab platform.
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A dark brown roast Coffee blend is less effective at stimulating gastric acid secretion in healthy volunteers compared to a medium roast market blend.
Molecular nutrition & food research, 2014Co-Authors: Malte Rubach, Herbert Stiebitz, Gerhard Bytof, Ingo Lantz, Roman Lang, Thomas Hofmann, Veronika SomozaAbstract:Coffee consumption sometimes is associated with symptoms of stomach discomfort. This work aimed to elucidate whether two Coffee Beverages, containing similar amounts of caffeine, but differing in their concentrations of (β) N-alkanoyl-5-hydroxytryptamides (C5HTs), chlorogenic acids (CGAs), trigonelline, and N-methylpyridinium (N-MP) have different effects on gastric acid secretion in healthy volunteers. The intragastric pH after administration of bicarbonate with/without 200 mL of a Coffee Beverage prepared from a market blend or dark roast blend was analyzed in nine healthy volunteers. Coffee Beverages were analyzed for their contents of C5HT, N-MP, trigonelline, CGAs, and caffeine using HPLC-DAD and HPLC-MS/MS. Chemical analysis revealed higher concentrations of N-MP for the dark brown blend (87 mg/L) compared to the market blend Coffee (29 mg/L), whereas concentrations of C5HT (0.012 versus 0.343 mg/L), CGAs (323 versus 1126 mg/L), and trigonelline (119 versus 343 mg/L) were lower, and caffeine concentrations were similar (607 versus 674 mg/mL). Gastric acid secretion was less effectively stimulated after administration of the dark roast blend Coffee compared to the market blend. Future studies are warranted to verify whether a high ratio of N-MP to C5HT and CGAs is beneficial for reducing Coffee-associated gastric acid secretion.
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Activity-guided fractionation to characterize a Coffee Beverage that effectively down-regulates mechanisms of gastric acid secretion as compared to regular Coffee
Journal of agricultural and food chemistry, 2010Co-Authors: Malte Rubach, Thomas Hofmann, Roman Lang, Carola Skupin, Veronika SomozaAbstract:In some individuals, the consumption of Coffee Beverages is related to symptoms of gastric irritation. Hot water steam-treatment of raw Coffee beans is hypothesized to reduce the contents of stomach irritating compounds, and products to which this technology is applied are launched as stomach-friendly Coffee. However, data on the effect of steam-treated Coffee on gastric acid secretion are conflicting and it has not been proven yet as to which Coffee components act as pro- or antisecretory stimulants. The work presented here aimed at the characterization of a Coffee Beverage that effectively down-regulates mechanisms of proton secretion in human gastric cells (HGT-1). At first, a regular Coffee Beverage was fractionated by using solvents of different polarity: water, ethylacetate, dichloromethane, and pentane. Functional assays on the proton secretory activity (PSA) of these solvent fractions revealed the least pronounced effect for the water fraction, for which quantitative analyses demonstrated the high...
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Quantitative Studies on the Formation of Phenol/2-Furfurylthiol Conjugates in Coffee Beverages toward the Understanding of the Molecular Mechanisms of Coffee Aroma Staling
Journal of agricultural and food chemistry, 2007Co-Authors: Christoph Müller, Thomas HofmannAbstract:To gain a more comprehensive knowledge of the contribution of recently identified phenol/thiol conjugates to the storage-induced degradation of odorous thiols, the concentrations of the sulfury-roasty smelling key odorant 2-furfurylthiol and the concentrations of the putative thiol-receptive di- and trihydroxybenzenes pyrogallol (1), hydroxyhydroquinone (2), catechol (3), 4-ethylcatechol (4), 4-methylcatechol (5), and 3-methylcatechol (6), as well as of the phenol/thiol conjugates 3-[(2-furylmethyl)sulfanyl]catechol (7), 3-[(2-furylmethyl)sulfanyl]-5-ethylcatechol (8), 4-[(2-furylmethyl)sulfanyl]hydroxyhydroquinone (9), and 3,4-bis[(2-furylmethyl)sulfanyl]hydroxyhydroquinone (10) were quantitatively determined in fresh and stored Coffee Beverages by means of stable isotope dilution analyses (SIDA). Although 2 was found to be the quantitatively predominant trihydroxybenzene in freshly prepared Coffee brew, this compound exhibited a very high reactivity and decreased rapidly during Coffee storage to generate the conjugates 9 and 10. After only 10 min, about 60% of the initial amount of 2-furfurylthiol in a Coffee Beverage reacted with 2 to give 9 and 10. In contrast, conjugate 7 was found to be exclusively formed during Coffee roasting because its initial concentration as well as the amount of its putative precursor, phenol 3, was not affected by storage. It is interesting to note that the concentration of 8 was increased with increasing incubation time, but its putative precursor 4 was not affected, thus indicating another formation pathway most likely via the chlorogenic acid degradation product 4-vinylcatechol. This study demonstrates for the first time that the loss of 2-furfurylthiol during Coffee storage is mainly due to the oxidative coupling of the odorant to hydroxyhydroquinone (2), giving rise to the conjugates 9 and 10.
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Bioresponse-guided decomposition of roast Coffee Beverage and identification of key bitter taste compounds
European Food Research and Technology, 2005Co-Authors: Oliver Frank, Gerhard Zehentbauer, Thomas HofmannAbstract:Sensory-guided fractionation of a roasted Coffee brew by means of sequential solvent extraction, ultrafiltration, and RP-HPLC demonstrated a group of ethyl acetate soluble compounds formed from O -hydroxycinnamoyl quinic acid derivatives upon Coffee roasting as the key compounds contributing to the bitter taste of roasted Coffee Beverages. LC-MS/MS studies, 1D- and 2D-NMR spectroscopy, syntheses, and model roast experiments with 5- O -caffeoyl- and 5- O -feruloylquinic acid led to the unequivocal identification of 3- O -caffeoyl-γ-quinide ( 2a ), 4- O -caffeoyl-γ-quinide ( 3a ), 5- O -caffeoyl- epi -δ-quinide ( 4a ), 4- O -caffeoyl- muco -γ-quinide ( 5a ), 5- O -caffeoyl- muco -γ-quinide ( 6a ), 3- O -feruloyl-γ-quinide ( 2b ), and 4- O -feruloyl-γ-quinide ( 3b ) as intense Coffee bitter tastants. Besides these individual bitter compounds, a highly complex and intensely bitter HPLC fraction was isolated from the ethyl acetate extractables of Coffee brew. Application of COSY spectroscopy and alkaline hydrolytic degradation gave strong evidence that the bitter taste of that fraction is due to a multiplicity of rather complex quinic acid lactone isomers multiply esterified with p -coumaric acid, caffeic acid, ferulic acid, 3,4-dimethoxycinnamic acid, and quinic acid, respectively. As representatives of this fraction, 3,4- O -dicaffeoyl-γ-quinide ( 10 ), 3,5- O -dicaffeoyl- epi -δ-quinide ( 11 ), and 4,5- O -dicaffeoyl- muco -γ-quinide ( 12 ) have been isolated, purified, and identified as strongly bitter-tasting compounds in roasted Coffee. For the first time, bitter taste recognition thresholds were determined for the individual compounds showing that, strongly depending on their chemical structure, the bitter threshold levels ranged between 9.8 and 180 μmol/l (water).
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Screening of raw Coffee for thiol binding site precursors using "in bean" model roasting experiments.
Journal of agricultural and food chemistry, 2005Co-Authors: Christoph Müller, Thomas HofmannAbstract:The purpose of the following study was to investigate the influence of Coffee roasting on the thiol-binding activity of Coffee Beverages, and to investigate the potential of various green bean compounds as precursors of thiol-binding sites by using promising “in bean” model roast experiments. Headspace gas chromatographic analysis on Coffee brews incubated in the presence of the roasty−sulfury smelling 2-furfurylthiol for 20 min at 30 °C in septum-closed vessels revealed that the amounts of “free” thiol decreased drastically with increasing the roasting degree of the beans used for preparation of the brews. A half-maximal binding capacity (BC50) of 183 mg of 2-furfurylthiol per liter of standard Coffee Beverage was determined for a roasted Coffee (CTN value of 67), thus demonstrating that enormous amounts of the odor-active thiol are “bound” by the Coffee. Furthermore, biomimetic “in bean” precursor experiments have been performed in order to elucidate the precursor for the thiol-binding sites in the raw ...