Determination of Caffeine in Coffee by Means Fourier Transform Infrared Spectrometry
In this work a flow analysis-Fourier transform infrared spectrometric (FA-FTIR) method for the determination of caffeine in coffee was developed. The method involves the extraction, in batch, of caffeine from solid samples of roasted coffee with hot water (80°C), on-line retro-extraction of caffeine...
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| Format: | Article |
| Language: | English |
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Universidad del Zulia
2009-07-01
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| Series: | Revista Técnica de la Facultad de Ingeniería |
| Online Access: | https://www.produccioncientificaluz.org/index.php/tecnica/article/view/6302 |
| _version_ | 1811201874885345280 |
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| author | Máximo Gallignani Marifred Torres Carlos Ayala María del Rosario Brunetto |
| author_facet | Máximo Gallignani Marifred Torres Carlos Ayala María del Rosario Brunetto |
| author_sort | Máximo Gallignani |
| collection | DOAJ |
| description | In this work a flow analysis-Fourier transform infrared spectrometric (FA-FTIR) method for the determination of caffeine in coffee was developed. The method involves the extraction, in batch, of caffeine from solid samples of roasted coffee with hot water (80°C), on-line retro-extraction of caffeine in chloroform and direct analysis of the organic phase by FTIR spectrometry. The measurement criterion selected for the quantification of caffeine was the absolute peak-valley value (1668-1649 cm”“1) of the first order derivate of the absorption spectrum, corresponding to the 1659 cm”“1 band. The method provides a limit of detection (3[1]) of 0.001% (w/v) caffeine, a relative standard deviation corresponding to the whole procedure, until the sample preparation, of 1.2% ([Caffeine] ≈0.05% (w/v), n = 5) andasample throughput (triplicate) of approximately 12 samples h”“1. The method was validated by means of standard addition, recovery and inter-day precision studies and by comparative analysis of real samples with the official chromatographic-spectrophotometric procedure. The method was applied to the analysis of commercial samples, obtaining a caffeine content ranging from 0.60 to 1.16% (w/w).
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| first_indexed | 2024-04-12T02:29:16Z |
| format | Article |
| id | doaj.art-cf9992aafb27448984160d1a35c5eaf4 |
| institution | Directory Open Access Journal |
| issn | 0254-0770 2477-9377 |
| language | English |
| last_indexed | 2024-04-12T02:29:16Z |
| publishDate | 2009-07-01 |
| publisher | Universidad del Zulia |
| record_format | Article |
| series | Revista Técnica de la Facultad de Ingeniería |
| spelling | doaj.art-cf9992aafb27448984160d1a35c5eaf42022-12-22T03:51:51ZengUniversidad del ZuliaRevista Técnica de la Facultad de Ingeniería0254-07702477-93772009-07-01312Determination of Caffeine in Coffee by Means Fourier Transform Infrared SpectrometryMáximo Gallignani0Marifred Torres1Carlos Ayala2María del Rosario Brunetto3Laboratorio de Espectroscopía Molecular, Unidad de Cromatografía & Espectroscopía Molecular, Departamento de Química, Facultad de Ciencias, Universidad de los Andes (ULA).Laboratorio de Espectroscopía Molecular, Unidad de Cromatografía & Espectroscopía Molecular, Departamento de Química, Facultad de Ciencias, Universidad de los Andes (ULA).Laboratorio de Espectroscopía Molecular, Unidad de Cromatografía & Espectroscopía Molecular, Departamento de Química, Facultad de Ciencias, Universidad de los Andes (ULA).Laboratorio de Espectroscopía Molecular, Unidad de Cromatografía & Espectroscopía Molecular, Departamento de Química, Facultad de Ciencias, Universidad de los Andes (ULA).In this work a flow analysis-Fourier transform infrared spectrometric (FA-FTIR) method for the determination of caffeine in coffee was developed. The method involves the extraction, in batch, of caffeine from solid samples of roasted coffee with hot water (80°C), on-line retro-extraction of caffeine in chloroform and direct analysis of the organic phase by FTIR spectrometry. The measurement criterion selected for the quantification of caffeine was the absolute peak-valley value (1668-1649 cm”“1) of the first order derivate of the absorption spectrum, corresponding to the 1659 cm”“1 band. The method provides a limit of detection (3[1]) of 0.001% (w/v) caffeine, a relative standard deviation corresponding to the whole procedure, until the sample preparation, of 1.2% ([Caffeine] ≈0.05% (w/v), n = 5) andasample throughput (triplicate) of approximately 12 samples h”“1. The method was validated by means of standard addition, recovery and inter-day precision studies and by comparative analysis of real samples with the official chromatographic-spectrophotometric procedure. The method was applied to the analysis of commercial samples, obtaining a caffeine content ranging from 0.60 to 1.16% (w/w). https://www.produccioncientificaluz.org/index.php/tecnica/article/view/6302 |
| spellingShingle | Máximo Gallignani Marifred Torres Carlos Ayala María del Rosario Brunetto Determination of Caffeine in Coffee by Means Fourier Transform Infrared Spectrometry Revista Técnica de la Facultad de Ingeniería |
| title | Determination of Caffeine in Coffee by Means Fourier Transform Infrared Spectrometry |
| title_full | Determination of Caffeine in Coffee by Means Fourier Transform Infrared Spectrometry |
| title_fullStr | Determination of Caffeine in Coffee by Means Fourier Transform Infrared Spectrometry |
| title_full_unstemmed | Determination of Caffeine in Coffee by Means Fourier Transform Infrared Spectrometry |
| title_short | Determination of Caffeine in Coffee by Means Fourier Transform Infrared Spectrometry |
| title_sort | determination of caffeine in coffee by means fourier transform infrared spectrometry |
| url | https://www.produccioncientificaluz.org/index.php/tecnica/article/view/6302 |
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