Thermal stability of spent coffee ground polysaccharides: galactomannans and arabinogalactans.

@article{Simoes2014ThermalSO,
  title={Thermal stability of spent coffee ground polysaccharides: galactomannans and arabinogalactans.},
  author={Joana Simões and {\'E}lia Maricato and Fernando M. Nunes and Maria do Ros{\'a}rio Domingues and Manuel A. Coimbra},
  journal={Carbohydrate polymers},
  year={2014},
  volume={101},
  pages={
          256-64
        }
}
In order to better understand the thermal stability of spent coffee grounds (SCG) galactomannans and arabinogalactans and the reactions that can occur upon roasting, long term isothermal exposures, up to 3h, were performed at 160, 180, 200, 220, and 240 °C. The resultant products were analysed according to the sugars and linkage composition and also by electrospray mass spectrometry. Galactomannans did not loss mass at T ≤ 200 °C during exposures up to 3h whereas the arabinogalactans showed… 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
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
Structural features of spent coffee grounds water-soluble polysaccharides: Towards tailor-made microwave assisted extractions.
TLDR
This study shows that the optimum conditions for polysaccharides extraction cannot be selected only by mass yield but need to be defined according to the desired structural features for the specific applications. Expand
Extraction of polysaccharides by autohydrolysis of spent coffee grounds and evaluation of their antioxidant activity.
TLDR
Autohydrolysis was demonstrated to be an efficient technique to recover antioxidant polysaccharides from SCG, which presented high antioxidant activity, were thermostable in a large range of temperature, and had a typical carbohydrate pattern, being of interest for industrial applications, mainly in the food area. Expand
Structural characterization of aerogels derived from enzymatically oxidized galactomannans of fenugreek, sesbania and guar gums.
TLDR
Hydrogel formation is due to oxidation of primary hydroxyl groups to carbonyl and carboxyl groups and subsequent formation of hemiacetal and ester bonds, and results show that Fenugreek displays the highest stability, compared to guar and sesbania rehydrated aerogels. Expand
Extraction of oligosaccharides and phenolic compounds by roasting pretreatment and enzymatic hydrolysis from spent coffee ground
Spent coffee ground (SCG) is the waste generated during the preparation of instant coffee and is the source of industrially valuable organic compounds. In this article, SCG was pretreated by roastingExpand
Structure-function relationship of immunostimulatory polysaccharides
Coffee polysaccharides, namely the arabinogalactans present in instant coffee and the galactomannans of coffee infusions have in vitro immunostimulatory activity, shown by an inflammatory response.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
Influence of molecular weight on in vitro immunostimulatory properties of instant coffee.
TLDR
The surface expression of CD69 (early activation marker) on different lymphocyte sub-populations showed that the fraction with 1-5kDa was able to induce activation of B-lymphocytes, since all the other fractions failed, even when higher concentrations were used. Expand
Structural polymeric features that contribute to in vitro immunostimulatory activity of instant coffee.
TLDR
Results show the relevance of single arabinose residues, present at the non-reducing end of polymeric compounds, to the coffee stimulatory activity in cells mediating innate and acquired immunity. Expand
...
1
2
3
...

References

SHOWING 1-10 OF 22 REFERENCES
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
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
Evaluation of the effect of roasting on the structure of coffee galactomannans using model oligosaccharides.
TLDR
The conclusion that transglycosylation and isomerization reactions occur during dry thermal processing of coffee galactomannans is made. 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
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
Coffee bean arabinogalactans: acidic polymers covalently linked to protein.
TLDR
An investigation of the structural features of the major AG fraction, released following enzymatic hydrolysis of the mannan-cellulose polymers, allowed a partial structure of coffee arabinogalactan to be proposed. 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
Demonstration of the presence of acetylation and arabinose branching as structural features of locust bean gum galactomannans
Abstract Galactomannans from locust bean gum (LBG) are polysaccharides containing single Gal p residues as side chains in a β-(1 → 4)-Man p backbone. Nevertheless, sugars other than mannose andExpand
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
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
...
1
2
3
...