Determination of Caffeine Content in Arabica and Robusta Green Coffee of Indian Origin

The coffee tree belongs to the Rubiaceae family, genus Coffea. Although more than 80 species of coffee have been identified worldwide, only two are economically important. Coffea Arabica, also known as Arabica coffee, is responsible for about 70 percent of the world coffee market, and Coffea Canephora or Robusta coffee represents the rest. Due to the strong physiological effects of caffeine on human physiology, the caffeine content is a very important quality parameter of processed coffee. Routine analysis of caffeine in the food industry can be facilitated using fast and reliable tests. In this article, we quantitatively determined the caffeine content using the chloroform isolation method and we also performed the qualitative determination of caffeine in green coffee of Indian origin by the UV-VIS spectrophotometric method. Following the analysis of caffeine isolate with chloroform, we obtained a caffeine content of 182 mg / 100 g for the Robusta green coffee sample and 154 mg / 100 g for the Arabica green coffee sample. Thus we can confirm the presence of a higher caffeine content in the Robusta India green coffee sample than in the Arabica India green coffee sample. In the spectrophotometric analysis we used 4 coffee samples obtained by extraction with hot distilled water and by extraction with cold distilled water. The spectral analysis confirms the presence of caffeine in both studied coffee species and agrees with the data in the literature.

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Determination of Three Main Chlorogenic Acids in Water Extracts of Coffee Leaves by Liquid Chromatography Coupled to an Electrochemical Detector

Antioxidants ◽

10.3390/antiox7100143 ◽

2018 ◽

Vol 7 (10) ◽

pp. 143 ◽

Cited By ~ 4

Author(s):

Rocío Rodríguez-Gómez ◽

Jérôme Vanheuverzwjin ◽

Florence Souard ◽

Cédric Delporte ◽

Caroline Stevigny ◽

...

Keyword(s):

Liquid Chromatography ◽

Coffea Arabica ◽

Limit Of Detection ◽

Coffea Canephora ◽

Antioxidant Compounds ◽

Chlorogenic Acids ◽

Coffea Species ◽

Coffee Species ◽

Coffea Liberica

Coffee is a beverage widely consumed in the world. The coffee species most commercialized worldwide are Arabica (Coffea arabica) and Robusta (Coffea canephora). Roasted coffee beans are the most used, but coffee leaves are also consumed as infusion in several countries for traditional medicinal purposes. They contain several interesting phenolic antioxidant compounds mainly belonging to chlorogenic acids (CGAs). In the present work, a liquid chromatography-electrochemical detection (LC-EC) method was developed for the determination of three main chlorogenic acid isomers, namely 3-, 4-, and 5-caffeoylquinic acids (CQA), in coffee leaves aqueous extracts. Samples from eight coffee species, namely; Coffea arabica, Coffea canephora, Coffea liberica, Coffea humilis, Coffea mannii, Coffea charrieriana, Coffea anthonyi, and Coffea liberica var. liberica, were grown and collected in tropical greenhouses. Linearity of the calibration graphs was observed in the range from the limit of quantification to 1.0 × 10−5 M, with R2 equal to 99.9% in all cases. High sensitivity was achieved with a limit of detection of 1.0 × 10−8 M for 3-CQA and 5-CQA (i.e., 3.5 µg/L) and 2.0 × 10−8 M for 4-CQA (i.e., 7.1 µg/L). The chromatographic profile of the samples harvested for each Coffea species was studied comparatively. Obtained raw data were pretreated for baseline variations and shifts in retention times between the chromatographic profiles. Principal Component Analysis (PCA) was applied to the pretreated data. According to the results, three clusters of Coffea species were found. In the water sample extracts, 5-CQA appeared to be the major isomer, and some species contained a very low amount of CQAs. Fluctuations were observed depending on the Coffea species and harvesting period. Significant differences between January and July were noticed regarding CQAs content. The species with the best CQAs/caffeine ratio was identified. The LC-EC data were validated by liquid chromatography-high resolution mass spectrometry (LC-HRMS).

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Reliable Discrimination of Green Coffee Beans Species: A Comparison of UV-Vis-Based Determination of Caffeine and Chlorogenic Acid with Non-Targeted Near-Infrared Spectroscopy

Foods ◽

10.3390/foods9060788 ◽

2020 ◽

Vol 9 (6) ◽

pp. 788

Author(s):

Adnan Adnan ◽

Marcel Naumann ◽

Daniel Mörlein ◽

Elke Pawelzik

Keyword(s):

Chlorogenic Acid ◽

Near Infrared ◽

Nir Spectroscopy ◽

Coffea Canephora ◽

Green Coffee ◽

Linear Discriminant ◽

Green Coffee Beans ◽

Coffee Beans ◽

Vis Spectroscopy

Species adulteration is a common problem in the coffee trade. Several attempts have been made to differentiate among species. However, finding an applicable methodology that would consider the various aspects of adulteration remains a challenge. This study investigated an ultraviolet–visible (UV-Vis) spectroscopy-based determination of caffeine and chlorogenic acid contents, as well as the applicability of non-targeted near-infrared (NIR) spectroscopy, to discriminate between green coffee beans of the Coffea arabica (Arabica) and Coffea canephora (Robusta) species from Java Island, Indonesia. The discrimination was conducted by measuring the caffeine and chlorogenic acid content in the beans using UV-Vis spectroscopy. The data related to both compounds was processed using linear discriminant analysis (LDA). Information about the diffuse reflectance (log 1/R) spectra of intact beans was determined by NIR spectroscopy and analyzed using multivariate analysis. UV-Vis spectroscopy attained an accuracy of 97% in comparison to NIR spectroscopy’s accuracy by selected wavelengths of LDA (95%). The study suggests that both methods are applicable to discriminate reliably among species.

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Development of new analytical methods for the determination of caffeine content in aqueous solution of green coffee beans

Chemistry Central Journal ◽

10.1186/s13065-017-0356-3 ◽

2017 ◽

Vol 11 (1) ◽

Cited By ~ 7

Author(s):

Blen Weldegebreal ◽

Mesfin Redi-Abshiro ◽

Bhagwan Singh Chandravanshi

Keyword(s):

Aqueous Solution ◽

Analytical Methods ◽

Green Coffee ◽

Caffeine Content ◽

Green Coffee Beans ◽

Coffee Beans

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Detection of Foreign Enzyme Addition into the Adulterated Honey

Czech Journal of Food Sciences ◽

10.17221/1066-cjfs ◽

2009 ◽

Vol 27 (Special Issue 1) ◽

pp. S280-S282 ◽

Cited By ~ 5

Author(s):

M. Voldřich ◽

A. Rajchl ◽

H. Čížková ◽

P. Cuhra

Keyword(s):

Substrate Specificity ◽

Standard Procedure ◽

Hydrolytic Activity ◽

Salivary Secretion ◽

Quality Parameter ◽

High Fructose Corn Syrup ◽

High Fructose ◽

Important Quality ◽

Natural Honey

Natural honey contains several enzymes, which are produced by bees (salivary secretion) and some are found in the nectar or pollen. The most important enzymes are amylases, invertases, glusidases, catalases, fosfatases and other. The activity of diastase (α-, β-, γ-amylase) is the important quality parameter of honey, according to the Directive 2001/110/CE the diastase activity (diastase number) must not be less than or equal to 8, for some kinds of honey also higher or equal to 3 (in these cases the HMF must not be higher than 15 mg/kg). Diastase is used as a marker to evaluate the freshness or the heat damage of honey. When honey is adulterated by addition of inverted sucrose or hydrolysed starch namely high fructose corn syrup (HFCS), then such dilution of honey leads to the reduction of diastase number. Such adulteration can be masked by addition of foreign amylases, e.g. bakery mould amylases. Recently several suspect samples of honey with inconsistent diastase number were found in the market. The possibilities of detection of foreign amylase addition based on the comparison of diastase determination using the Schade and Phadebas procedures are evaluated. The both tests are based on the determination of hydrolytic activity (the Schade number is expressed as g of starch hydrolysed 1 h at 40°C per 100 g honey), but the results depend on the substrate used for the trial (according to the standard procedure an insoluble blue dyed cross-linked type of starch should be used). The results of Schade test are therefore often affected by the choice of substrate. The model samples of honeys with addition of foreign amylase (<I>Aspergillus oryzae</I>) were analysed, the methods of adulteration detection based on the substrate specificity of enzymes is proposed. Keywords: falsification; honey; diastase number; Schade; amylase addition

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