PREPARATION OF CANDIDATE OF REFERENCE MATERIAL FOR THE DETERMINATION OF CAFFEINE IN ARABICA COFFEE BEANS BY THIN LAYER CHROMATOGRAPHY (TLC) SCANNER

• Main Author: PUTRI R (NIM : 10508039); Pembimbing : Prof. Dr. Buchari, DILLANI
• Format: Final Project
• Language: Indonesia
• Online Access: https://digilib.itb.ac.id/gdl/view/15398
• Institution: Institut Teknologi Bandung

Coffee (Coffea sp) is one of the commodity crops that are traded around the world. Coffee is widely consumed as a beverage and food because it has a distinctive aroma and flavor. Flavor and aroma of coffee is determined by the content of chemicals in it, especially caffeine and trigonelin. In this research, candidat reference materials for the determination of caffeine content be made from Arabica coffea beans using TLC scanner. Reference material is a material that has certain properties that are sufficiently homogeneous and stable used for the validation of analytical methods or instruments. Preparation of candidate reference materials performed include analysis of water content, ash content, metal content and caffeine content. Moisture content and ash content were analyzed by gravimetric methods, while the metal content was measured using atomic absorption spectrophotometer (AAS). Moisture content and ash content average of 10 samples gave values measured in succession (4.60 + 0.17) % and (3.11 + 0.10) %. The average values of Fe content which obtained from the 10 samples is (49.82 + 1.99) mg/kg and analysis of Zn metal content gives result (34,41 + 1,04) mg/kg. Analysis content of caffeine in the samples was conducted by thin-layer chromatography (TLC) on aluminum plates coated with silica using ethyl acetate: acetic acid: formic acid: water (100:11:11:25) as eluent. Furthermore, the separation was <br /> <br /> <br /> <br /> <br /> scanned using a Camag TLC scanner at a wavelength of 272 nm. Determination of caffeine content is done by comparing the area of the caffeine standards and samples using a <br /> <br /> <br /> <br /> <br /> calibration curve. Caffeine content that obtained from measurements of 10 samples is (1.04 + 0.11) %. Validation of measurement methods include the determination of the detection limit, quantitation limit, linearity, homogeneity testing and stability testing.