![]() ![]() ![]() īrereton RG (2018) Chemometrics: data driven extraction for science, Second Edition. īrandt M, Silva NS (2014) A coleta da erva-mate pela população cabocla do vale do rio do peixe e oeste de santa catarina: apropriação privada da terra e rupturas (décadas de 1900 a 1940). Graphical AbstractīonfattiJúnior EA, Lengowski EC, LudkaJúnior A (2018) Mapeamento do processo produtivo de erva-mate. This indicates that the caffeine synthesis in yerba mate plants represents an adaptative strategy to elevated light conditions. Principal component analysis of the NIR spectra demonstrated that shading affected the chemical composition more in high-caffeine clones than in decaffeinated ones. Wilcoxon signed classification, sign classification in pairs, and randomization t-tests showed an excellent model fit. Specificity greater than 97.12% was found for both sets, with an efficiency rate of 96.82% for the training set and 95.31% for the test set. The PLS-DA model showed a sensitivity of 96.52% for the training set and 93.33% for the test set. Robustness of the mathematical model was verified for plants with all these shading levels. Yerba mate plants were cultivated in the semi-hydroponic system under five plant shading levels (0%, 40%, 51%, 76%, and 82%). Partial least squares-discriminant analysis (PLS-DA) was used to identify chemically differentiated yerba mate plants together with reflectance measurement (900–1700 nm) near-infrared spectroscopy (NIRS) in direct analysis of plant material. Quality control strategies for this type of food are essential, and multivariate tools can help in this procedure. Genetically improved yerba mate clones are classified into two groups of interest to a selective consumer public, decaffeinated and high caffeine plants. Cambridge, UK: Royal Society of Chemistry, 2013., p.Yerba mate plants are part of the ombrophilous mixed forest with araucaria trees. The Merck Index - An Encyclopedia of Chemicals, Drugs, and Biologicals. Caffeine overdose can result in a state of central nervous system over-stimulation called caffeine intoxication.Ĭaffeine should be kept in plastic or glass bottles, away from light and corrosive fumes. Side effects include elevated blood pressure, restlessness, insomnia, headaches. NileRed made a video on this process.Ĭaffeine, as found in coffee and tea, has stimulant effects when consumed. Similar to above, though the yields are much lower. The crude caffeine can be further purified via sublimation. The crude caffeine crystals are filtered using a filter paper or fritted funnel and dried. The solution is cooled to recrystallize the caffeine. After all the DCM has been removed from the flask, it is transferred in another beaker, where hot water is added until it completely dissolves. The filtrate is transferred in a round bottom flask, which is connected to a distillation setup or a rotary evaporator to remove and recover the DCM via distillation. The suspension is left to decant, then filtered using a fritted funnel (or funnel with a proper filter paper), to remove the solid. To the powder from the beaker, a volume of dichloromethane is added and the suspensions is stirred for a few minutes. The fine powder is then transferred into a flask or beaker. Extracting it from readily available sources is the only economical way to get useful amounts.Ĭrush a desired amount of caffeine pills in a mortar until they are turned into a fine powder. It's not economical to make caffeine from precursors. It shows good solubility in dichloromethane and chloroform.Ĭaffeine is available as pills in most pharmacies and drugstores.Ĭaffeine is more readily available in the form of coffee. Reaction with citric acid will give caffeine citrate.Ĭaffeine is an odorless white solid, slightly soluble in water, though its solubility increases with temperature and the addition of an acid. Caffeine reacts with acids to give salts of caffeine. ![]()
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