The Use of Solid State NMR to Evaluate the Carbohydrates in Commercial Coffee Granules
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- 3 Departamento de Química da Universidade Federal de S?o Carlos, Rodovia Washington Luis, S?o Carlos, SP, Brasil
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Abstract
Coffee brings many health benefits due to its chemical constituents. Based on this information, it is essential to know the main chemical compounds from coffee granules; the intermolecular interaction among the coffees compounds and the molecular components homogeneity. In this study six types of roasted commercial coffee were evaluated by solid state nuclear magnetic resonance (NMR), employing carbon-13 (<sup>13</sup>C) and hydrogen (<sup>1</sup>H) nucleus. Carbon-13 was analyzed applying high field NMR techniques, such as: magic angle spinning (MAS); magic angle spinning with cross-polariza- tion (CPMAS) and magic angle spinning with cross-polarization and dipolar dephasing (CPMASDD). The hydrogen was evaluated via relaxation times. Proton spin-lattice relaxation time in the rotating frame was deter-mined through the carbon-13 decay, during the variable contact-time experiment, using high field NMR. Proton spin-lattice relaxation time was determined through the inversion-recovery pulse sequence, using low field NMR. Considering all NMR results, it was concluded that the major coffee compounds are: a) triacilglycerides, which constitute the mobile region in the granule coffee and b) Carbohydrates such as: polysaccharides and fibers that belong to the rigid domain. These constituents belong to different molecular mobility domain, although they have strong intermolecular interactions due to the granule organization.
- M. El Yacoubi, et al., “The Stimulant Effects of Caffeine on Locomotor Behaviour in Mice are Mediated through Its Blockade of Adenosine A2A Receptors,” British Journal of Pharmacology, Vol. 129, No. 7, 2000, pp. 1465- 1473. doi:10.1038/sj.bjp.0703170
- J. W. Daly and B. B. Fredholm, “Caffeine—An Atypical Drug of Dependence,” Drug and Alcohol Dependence, Vol. 51, No. 1, 1998, pp. 199-206. doi:10.1016/S0376-8716(98)00077-5
- M. N. Clifford and J. R. Ramirez-Martinez, “Phenols and Caffeine in Wet-Processed Coffee Beans and Coffee Pulp,” Food Chemistry, Vol. 40, No. 1, 1991, pp. 35-42. doi:10.1016/0308-8146(91)90017-I
- A. M. N. G. Correia, et al., “Caffeoyl–Tyrosine and Angola II as Characteristic Markers for Angolan Robusta Coffees,” Food Chemistry, Vol. 53, No. 3, 1995, pp. 309- 313. doi:10.1016/0308-8146(95)93938-N
- A. Farah, et al., “Effect of Roasting on the Formation of Chlorogenic Acids Lactones in Coffee,” Journal of Agricultural and Food Chemistry, Vol. 53, No. 5, 2005, pp. 1505-1513. doi:10.1021/jf048701t
- J. L. B. Quintana, et al., “Alzheimer’s Disease and Coffee: A Quantitative Review,” Neurology Research, Vol. 29, No. 1, 2007, pp. 91-95. doi:10.1179/174313206X152546
- G. W. Arendash, et al., “Caffeine Protects Alzheimer’s Mice against Cognitive Impairment and Reduces Brain β-Amyloid Production,” Neuroscience, Vol. 142, No. 4, 2006, pp. 941-952. doi:10.1016/j.neuroscience.2006.07.021
- T. Giovannetti, et al., “Coffee with Jelly or Unbuttered Toast: Commissions and Omissions Are Dissociable Aspects of Everyday Action Impairment in Alzheimer’s Disease,” Neuropsychology, Vol. 22, No. 5, 2008, pp. 235-245. doi:10.1037/0894-4105.22.2.235
- F. Bravi, et al., “Coffee Drinking and Hepatocellular Carcinoma Risk: A Meta-Analysis,” Hepatology, Vol. 46, No. 2, 2007, pp. 430-435. doi:10.1002/hep.21708
- S. C. Larsson and A. Wolk, “Coffee Consumption and Risk of Liver Cancer: A Meta-Analysis,” Gastroenterology, Vol. 132, No. 5, 2007, pp. 1740-1745. doi:10.1053/j.gastro.2007.03.044
- K. Wakai, et al., “Liver Cancer Risk, Coffee, and Hepatitis C Virus Infection: A Nested Case-Control Study in Japan,” British Journal of Cancer, Vol. 97, 2007, pp. 426-428. doi:10.1038/sj.bjc.6603891
- J. Kotsopoulos, et al., “The CYP1A2 Genotype Modifies the Association between Coffee Consumption and Breast Cancer Risk among BRCA1 Mutation Carriers,” Cancer Epidemiol Biomarkers Prevention, Vol. 16, No. 5, 2007, pp. 912-916. doi:10.1158/1055-9965.EPI-06-1074