Evaluation of the effect of roasting on the structure of coffee galactomannans using model oligosaccharides.

@article{Moreira2011EvaluationOT,
  title={Evaluation of the effect of roasting on the structure of coffee galactomannans using model oligosaccharides.},
  author={A. Moreira and M. Coimbra and F. Nunes and Joana Simões and M. Domingues},
  journal={Journal of agricultural and food chemistry},
  year={2011},
  volume={59 18},
  pages={
          10078-87
        }
}
The roasting process induces structural changes in coffee galactomannans. To know more about the reaction pathways that occur during the roasting of coffee, mannosyl and galactomannosyl oligosaccharides, having a degree of polymerization (DP) between 3 and 4, were used as models for galactomannans. These compounds were dry-heated under air atmosphere from room temperature to 200 °C, being maintained at 200 °C for different periods of time. The roasted materials were analyzed by mass… Expand
Roasting-induced changes in arabinotriose, a model of coffee arabinogalactan side chains.
TLDR
Thermal processing can promote reactions that change the structure of food constituents, often by unknown mechanisms, such as those occurring in arabinose residues of coffee arabinogalactan side chains, which can contribute to their formation upon roasting. Expand
Nonenzymatic Transglycosylation Reactions Induced by Roasting: New Insights from Models Mimicking Coffee Bean Regions with Distinct Polysaccharide Composition.
TLDR
It is concluded that, depending on the distribution of the polysaccharides in the bean cell walls and the roasting conditions, different nonhybrid and hybrid structures can be formed during coffee roasting. Expand
Thermal stability of spent coffee ground polysaccharides: galactomannans and arabinogalactans.
TLDR
The roasting of galactomannans at 200 °C promoted their solubility in water upon alkali extraction and neutralisation and the formation of new glycosidic linkages, with occurrence of 2-, 6-, 2,3, 2,6-, 3,6, 3,4,6-linked mannose residues, and terminally-linked glucose residues, observed by methylation analysis. Expand
Transglycosylation reactions between galactomannans and arabinogalactans during dry thermal treatment.
TLDR
The results support the occurrence of transglycosylation reactions promoted by roasting involving both oligosaccharides in the starting mixtures, resulting in arabinan and mannan chimeric polysaccharides. Expand
Quantification of Sugar Epimers in Polygalactomannans by ESI-MS/MS
Polygalactomannans (PGMs) represent an important family of polysaccharides. They are obtained from the endosperm of leguminous plant seeds and are employed in a growing number of industrialExpand
Structural Characterization and in Vitro Fermentation of β-Mannooligosaccharides Produced from Locust Bean Gum by GH-26 endo-β-1,4-Mannanase (ManB-1601).
TLDR
DP2, DP3, and DP5 were found to inhibit the growth of Escherichia coli, Listeria monocytogenes and Salmonella typhi while DP5 resulted in poor growth of all Lactobacillus spp. Expand
Transglycosylation reactions, a main mechanism of phenolics incorporation in coffee melanoidins: Inhibition by Maillard reaction.
TLDR
The roasting of solid-state mixtures mimicking coffee beans composition allowed the conclusion that proteins play a regulatory role in TGRs extension and, consequently, modulate melanoidins composition. Expand
Galactomannans in Coffee
Abstract Galactomannans are the most abundant constituents of coffee beans. Generically, the structure of these polysaccharides consists of a linear backbone of β-(1→4)-linked d -mannose residues,Expand
Neutral and acidic products derived from hydroxyl radical-induced oxidation of arabinotriose assessed by electrospray ionisation mass spectrometry.
The oxidation of α-(1 → 5)-L-arabinotriose (Ara3), an oligosaccharide structurally related to side chains of coffee arabinogalactans, was studied in reaction with hydroxyl radicals generated underExpand
Extractability and structure of spent coffee ground polysaccharides by roasting pre-treatments.
The coffee residue left after the preparation of the brew (spent coffee grounds - SCG) is very rich in polysaccharides, namely galactomannans and arabinogalactans, which are polymers that can be usedExpand
...
1
2
3
4
5
...

References

SHOWING 1-10 OF 46 REFERENCES
Characterization of galactomannan derivatives in roasted coffee beverages.
TLDR
The galactomannans of roasted coffee infusions were purified by 50% ethanol precipitation, anion exchange chromatography, and phenylboronic acid-immobilized Sepharose chromatography to conclude that they are high molecular weight supports of low molecular weight brown compounds. Expand
Characterization of galactomannan derivatives in roasted coffee beverages.
In this work, the galactomannans from roasted coffee infusions were purified by 50% ethanol precipitation, anion exchange chromatography, and phenylboronic acid-immobilized Sepharose chromatography.Expand
Arabinosyl and glucosyl residues as structural features of acetylated galactomannans from green and roasted coffee infusions.
TLDR
Methylation analysis, hydrolysis with specific glycosidases and GC-EIMS analysis of the reduced and methylated oligosaccharides allowed to conclude that beta-(1-->4)-linked glucose residues are also structural features of green and roasted coffee galactomannans (6 and 1 mol%, respectively). Expand
Effect of roasting on degradation and structural features of polysaccharides in Arabica coffee beans.
TLDR
Polysaccharide degradation during roasting is more marked than previously documented, and points to roasting induced changes to the polysaccharides as major factors in the changing physicochemical profile of the coffee bean during processing. Expand
Chemical characterization of galactomannans and arabinogalactans from two arabica coffee infusions as affected by the degree of roast.
TLDR
The degree of polymerization and the degree of branching of the galactomannans decreased with the increase of the DR, and the terminally linked galactosyl residues increased. Expand
Structural features of partially acetylated coffee galactomannans presenting immunostimulatory activity
Abstract The galactomannans purified from coffee infusions have been shown to present in vitro immunostimulatory activity on murine B- and T-lymphocytes. These properties have also been shownExpand
Structural features of acetylated galactomannans from green Coffea arabica beans
Polysaccharides were extracted from green Coffea arabica beans with water (90 °C, 1 h). Galactomannans were isolated from the water extract using preparative anion-exchange chromatography. Almost allExpand
Glucosylisomaltol, a new indicator of browning reaction in baby cereals and bread.
TLDR
Glucosylisomaltol is a useful indicator to control the browning reaction during baby cereal storage and the baking of bread. Expand
Characterization of polysaccharides from green and roasted Coffea arabica beans
Abstract Polysaccharides were sequentially extracted from green and roasted Coffea arabica beans with water (90 °C), EDTA, 0.05, 1, and 4 M NaOH and characterized chemically. Additionally, the beansExpand
Fragmentation pattern of underivatised xylo-oligosaccharides and their alditol derivatives by electrospray tandem mass spectrometry
AbstractMaltopentaose and olive pulp xylo-oligosaccharides and the correspondent alditol derivatives were analysed by ESI-MS and ESI-MS/MS.The ESI-MS spectrum of maltopentaose and maltopentaoseExpand
...
1
2
3
4
5
...