An Overview of Techniques for Extracting Caffeine from Coffee for Quantification
Kasahun Wale,
Bealu Girma
Issue:
Volume 7, Issue 2, December 2023
Pages:
15-19
Received:
27 June 2023
Accepted:
17 July 2023
Published:
31 July 2023
Abstract: Coffee is one of the most important agricultural commodities. Of the coffee alkaloids, caffeine is the most common component. Caffeine in coffee affects the central nervous system, heart muscle, respiratory system, and stomach secretion, impacting health and defining the quality of the beverage. However, excessive caffeine consumption has health hazards such as worsening heart disease and raising blood pressure. Thus, the level of Caffeine in coffee determines its quality. The objective of this paper is to compare different extraction methods for caffeine. Several traditional (e g., conventional heat reflux extraction, fusion) and modern (e g., soxhlet extraction, Microwave Assisted extraction, MAE) methods have been optimized & reported to extract Caffeine from coffee before chromatographic and spectroscopic analysis. Conventional Extraction methods are time-consuming, offer lower recovery yields, and use more solvent, whereas modern Extraction methods are faster, more efficient, and give the maximum recovery yield. Microwave Assisted Extraction (MAE) has better Caffeine Extraction efficiency with similar time, and it uses less solvent. But it uses a power supply, in addition to time, temperature, and solvent, whereas with Conventional heat reflux extraction, there is no need for a power supply. On the other hand, water Extraction is better for being economically and environmentally friendly (non-toxic and easily available) as well as greater dielectric constant and polarity than alcohol. For Caffeine quantification, hyphenated methods such as HPLC and electro-analytical methods are preferable. Modern extraction methods are better for their efficiency, time, and volume of solvent required, while modern quantification methods are better for their accuracy and precision.
Abstract: Coffee is one of the most important agricultural commodities. Of the coffee alkaloids, caffeine is the most common component. Caffeine in coffee affects the central nervous system, heart muscle, respiratory system, and stomach secretion, impacting health and defining the quality of the beverage. However, excessive caffeine consumption has health ha...
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Research Article
Color Lightening Chemical Treatments for the Improvement of the Deep Red Colored Ruby Stones’ Quality
Hebah Abdel-Wahab*,
Tamara Gund,
Joseph Bozzelli
Issue:
Volume 7, Issue 2, December 2023
Pages:
20-23
Received:
30 November 2023
Accepted:
15 December 2023
Published:
26 December 2023
Abstract: Corundum mineral species include rubies and sapphires. The mineral corundum is a natural gemstone mined from earth, and is colorless in its purest form. Variations of its color can be caused by trace elements that become part of the mineral crystal structure. Ruby is a crystalline form of aluminum oxide (Al2O3) in a closed packed hexagonal structure and is a well-known corundum. Ruby is pink-red to blood red colored gemstone, and its color arises from chromium impurities. The color is determined by three criteria, saturation, tone and hue. The price and quality of the rubies is determined by its clarity, color, size, with the color being the most important factor in determining its grade. The objective of this work is to increase the quality of the red ruby stones by reducing their deep red color after the chemical treatment of the ruby ores. The current treatment involves the usage of hydrofluoric acid, borax, and the heating of the ruby ores at temperatures that exceeded 1300°C. The lead glass treatment of the stones should involve the usage of a stronger lightening agent to minimize the lightening process time, the treatment should also involve the usage of a colorful and suitable metal oxide to increase the stones’ quality instead of the white borax, and the heating temperature of the stones should not exceed 900C to prevent the deepening of the color of the stones and to prevent the color from reverting to the original deep red color before the chemical lightening diffusion treatment.
Abstract: Corundum mineral species include rubies and sapphires. The mineral corundum is a natural gemstone mined from earth, and is colorless in its purest form. Variations of its color can be caused by trace elements that become part of the mineral crystal structure. Ruby is a crystalline form of aluminum oxide (Al2O3) in a closed packed hexagonal structur...
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