Antioxidant and Sensory Assessment of Innovative Coffee Blends of Reduced Caffeine Content

Considering the current trend in the global coffee market, which involves an increased demand for decaffeinated coffee, the aim of the present study was to formulate coffee blends with reduced caffeine content, but with pronounced antioxidant and attractive sensory properties. For this purpose, green and roasted Arabica and Robusta coffee beans of different origins were subjected to the screening analysis of their chemical and bioactive composition using standard AOAC, spectrophotometric and chromatographic methods. From roasted coffee beans, espresso, Turkish and filter coffees were prepared, and their sensory evaluation was performed using a 10-point hedonic scale. The results showed that Arabica coffee beans were richer in sucrose and oil, while Robusta beans were characterized by higher content of all determined bioactive parameters. Among all studied samples, the highest content of 3-O-caffeoylquinic acid (14.09 mg g−1 dmb), 4-O-caffeoylquinic acid (8.23 mg g−1 dmb) and 5-O-caffeoylquinic acid (4.65 mg g−1 dmb), as well as caffeine (22.38 mg g−1 dmb), was detected in roasted Robusta beans from the Minas Gerais region of Brazil, which were therefore used to formulate coffee blends with reduced caffeine content. Robusta brews were found to be more astringent and recognized as more sensorily attractive, while Arabica decaffeinated brews were evaluated as more bitter. The obtained results point out that coffee brews may represent a significant source of phenolic compounds, mainly caffeoylquinic acids, with potent antioxidant properties, even if they have reduced caffeine content.

Rapid High-Performance Liquide Chromatographic Method for Quantitative Determination of Caffeine in Different Soft and Energy Drinks Available in Bangladesh

Caffeine is one of the commonly used food additives, which has unique flavor characteristics and bitter taste and used in soft drinks as flavor enhancer. An experimental study was designed to determine the concentration of caffeine in different brands of soft drinks and energy drinks available in Bangladesh by using HPLC. For chromatographic analysis, A Luna 5 C18 (2) 100A column (250×4.6 mm) was used at 37°C temperature at the wavelength of 272nm. Chromatographic separation was determined using buffer of sodium acetate and acetic acid with acetonitrile at a ratio of 80:20 (pH=4.0; flow rate of 1.0 ml/min). The results of this study showed that caffeine content in soft drinks ranged from 19.63 to 101.73 mg/100ml and highest concentration of caffeine found in brand 3 samples while lowest concentration found in brand 2 samples. Significantly higher concentration of caffeine (p<0.05) found in six soft drinks sample when compared to BSTI and FDA reference value except brand 2 sample (p>0.05). Quantification of caffeine in different brands of energy drink sample revealed that, four brand sample contained caffeine; among them brand 3 sample showed the highest levels of caffeine 295.86 mg/100ml and lowest amount found in brand 1 sample (101.74 mg/100ml). Concentration of Caffeine in soft and energy drinks exceeded the national and international standard recommended range hence this proposed HPLC method can be used for routine determination and control of caffeine content in different drinks.

Arjuna Coffee Organoleptic Test

The organoleptic test of coffee grown in the Toyomarto area aims to determine consumer preferences for coffee grown on the slopes of Mount Arjuna. The two types of coffee that are most in demand in the global market are Arabica and Robusta. When viewed from the level of consumption, around 70% of the world's population are consumers of Arabica coffee, which has a mild and aromatic taste. Meanwhile, the remaining 30% of the world's population are consumers of Robusta coffee, which has a bitter taste and 50% higher caffeine content than Arabica coffee. There is another type that is grown in Toyomarto, namely the Liberica type. Toyomarto Village, which is located in Singosari District, Malang Regency, is located at an altitude of 700-1200 masl. has a fertile soil that makes a specific and unique taste in the coffee that grows around it. Organoleptic testing has been carried out at 2 different locations. The panelists really liked the sour taste of Arabica coffee and the bitter taste of Robusta coffee. Meanwhile, Liberica coffee was less liked by the panelists.

The Analysis of Chlorogenic Acid and Caffeine Content and Its Correlation with Coffee Bean Color under Different Roasting Degree and Sources of Coffee (Coffea arabica Typica)

Coffee is one of the main economic crops in the world and is now widely grown throughout Taiwan. The process of roasting coffee begins with the heating and smooth expansion of raw beans, which leads to changes in appearance and color while affecting the flavor and taste of coffee. So far, most coffee manufacturers have used visual inspection or colorimeter methods to identify differences in coffee quality. Moreover, there is no literature discussing the correlation of roasted bean color with caffeine and chlorogenic acid content. Therefore, the purpose of this experiment was to analyze the chlorogenic acid and caffeine content and their correlation with bean color under different roasting degrees and from different sources to establish basic data for the rapid identification of coffee quality in the future. In this experiment, the coffee Coffea arabica typica from Dongshan, Gukeng, and Sumatra’s Indonesian rainforest was used, and the beans were roasted into four degrees: raw bean, light, medium, and dark roast, to investigate the appearance of the coffee beans and its correlation with caffeine and chlorogenic acid content. The results showed that with a higher roasting degree, caffeine content increased gradually, except for Indonesian beans, but the chlorogenic acid content in all samples showed a declining trend with the increase in roasting degree. The correlation between the chlorogenic acid content and the color space value of the coffee bean color shows that L*, a*, and h° in both ground and unground coffee are highly correlated. The C* value of the ground and unground coffee showed a correlation coefficient of r = 0.159 ns and 0.299 ns, respectively. The correlation between the caffeine content and the color space value of the unground coffee bean shows that the a*, b*, and C* value is highly correlated with the caffeine content. The color space values of ground coffee beans show no correlation with caffeine.

Exploring Secondary Metabolites in Coffee and Tea Food Wastes

Coffee and tea are popular beverages worldwide, and therefore generate large amounts of waste. Here we describe the caffeine content and phenolic profile in three types of teas and coffees, and how they vary with two successive extractions. Although the first extraction was far more efficient than the second, green tea also showed a high content of flavanols in the second extraction, as did mate tea for phenolic acids. Black tea could also be a good option since caffeine content was highest in both extractions. Water also proved to be the most effective solvent in almost all cases, which represent a major benefit for urban horticulture, as it is a simple extraction method from an easily accessible source. Coffee and tea residues are a rich source of caffeine and phenolic compounds that could potentially be used as alternatives to conventional pesticides.

Development of thin-layer chromatographic method for determination of caffeine in black, green, and white tea

Caffeine is naturally present in tea and coffee giving the pleasant and stimulant effect. Several different types of teas, black, green, and white teas bought in market were analysis for caffeine content. The boiled sample tea was filtered through filter paper. Lead(II) acetate was used to separate tannins from caffeine followed by filtration through filter paper with a black ribbon. The liquid-liquid extraction was carried out using dichloromethane (3×5 mL) and sodium sulfate as a drying agent. The TLC method was performed on Merck precoated silica gel plates 5×10 cm (60F254, 200 μm) using either methanol or dichloromethane as solvents and the mobile phases were glacial acetic acid and ethyl acetate (95:5, v/v), while the second one was consisted of ethyl acetate and ethanol (80:20, v/v), respectfully. The Rf values were 0.36 and 0.86 for the first and the second mobile phase, respectively, in comparison to the standard caffeine. The values for pH of boiled sample teas were in the range from 4.85 to 5.80. The most abundant tea sample for caffeine was determined in green tea bought in the grocery store for health nutrition (2.04 %). The yield for tea samples from green market, white tea and two tea black samples were 0.06, 0.71, 0.07, and 0.05%, respectively. The developed TLC method can be used for determination of caffeine content in tea samples.

Determining the Efficiency and Yield of Caffeine Extraction for Robusta and Arabica Coffee Beans

The objective of this review is to determine the difference in caffeine content in the coffee beans from different brands that are available in Costco. Two different popular coffee bean brands were bought and tested to determine which brand would have the highest caffeine content and their relative popularity among consumers. The extraction DMC method was conducted by using chemicals such as calcium carbonate, water, and DMC. The same amount of coffee beans were boiled with water until highly concentrated solutions were formed. Extraction funnel was utilized to wash out caffeine. Then, the recrystallization and vacuum filtration was utilized to obtain caffeine in solid form. The identity of the product along with the purity of the product was determined using melting temp, IR-spectroscopy, UV-vis spectrum, and TLC plating. The mass of caffeine produced from individual coffee brands were measured and compared. It was hypothesized that robusta coffee beans would yield more caffeine than arabica coffee beans. The expected results verify those claims as the data demonstrates that the amount of caffeine extracted from 10 grams of robusta coffee would be around .8021 grams, while the amount of caffeine extracted from 10 grams of arabica coffee would be around .4321 grams. The IR graph, UV-vis graph, and TLC plate were conducted to verify the identity of the product. The predicted IR graph, UV-vis graph, and TLC plate closely matched with the literature values, which indicates that the product produced is pure caffeine. One source of error that could skew the data could be the presence of impurities from the coffee beans that react in solution while we are trying to extract the caffeine. The broader impact of this review is that by understanding the caffeine content in different products, the medical and scientific field can further determine the difference in health effects between excess and optimal caffeine consumption to the human body. Additionally, scientists can research various medical usages of caffeine to help different patients with sleep disorders.

Development, Characterization, and Stability Evaluation of the Anti-Cellulite Emgel Containing Herbal Extracts and Essential Oils

Recently, the herbal compress was successfully developed and applied for cellulite treatment. The aim of this study was to formulate a more convenient dosage form of herbal application from the original formula. In addition, we aimed to characterize and evaluate the stability of the developed dosage form. A gelled emulsion, or an “emgel,” incorporated with 0.1 wt% tea and coffee extracts (1:1 ratio) plus 5 wt% essential oils (mixed oil) was prepared. The caffeine content in the finished product obtained from tea and coffee extracts analyzed by HPLC was 48.1 ± 2.3 µg/g. The bio-active marker monoterpenes of mixed oil characterized by headspace GCMS were camphene 50.8 ± 1.8 µg/mg, camphor 251.0 ± 3.2 µg/mg, 3-carene 46.7 ± 1.8 µg/mg, α-citral 75.0 ± 2.1 µg/mg, β-citral 65.6 ± 1.3 µg/mg, limonene 36.8 ± 6.7 µg/mg, myrcene 53.3 ± 4.5 µg/mg, α-pinene 85.2 ± 0.6 µg/mg, β-pinene 88.4 ± 1.1 µg/mg, and terpinene-4-ol 104.3 ± 2.6 µg/mg. The stability study was carried out over a period of 3 months at 4, 25, and 50 °C. The caffeine content showed no significant changes and passed the acceptance criteria of ≥80% at all tested temperatures. However, monoterpenes showed their stability for only 2 months at 50 °C. Therefore, the shelf-life of the emgel was, consequently, calculated to be 31 months using the Q10 method. Thus, the anti-cellulite emgel was successfully formulated. The characterization methods and stability evaluation for caffeine and monoterpenes in an emgel matrix were also successfully developed and validated.

Influence of Seasonal and Yearly Variation on Phenolic Profiles, Caffeine, and Antioxidant Activities of Green Tea (Camellia sinensis (L.) Kuntze) from Azores

This study compares the antioxidant properties (RSADPPH–DPPH radical scavenging activity, FRAP–ferric reducing activity power, and FIC–ferrous ion-chelating activity), the total phenolics (TP), total flavonoids (TF), and catechin profiles, as well as the caffeine content of Azorean Camellia sinensis green tea collected in seasons of two different years. The RSADPPH showed some variation between 2019 and 2020, and presented, in general, better results in 2020 as well as during the summer seasons. The FRAP was also noted to be at its highest in July and August of the two investigated years (6.64 and 6.40 µg/mL in 2019 and 5.85 and 5.46 µg/mL in 2020). According to FIC activity, the August 2019 sample exhibited the highest value (76.18%). The TP varied between 291.14 and 326.93 mg gallic acid equivalents (GAE)/g of dried extract (DE) in 2019 and between 300.25 and 320.58 mg GAE/g DE in 2020. Concerning the TF, the values varied between 51.85 and 67.93 mg rutin equivalents (RE)/g DE in 2019 and between 50.27 and 69.57 mg RE/g DE in 2020. Epicatechins derivatives, determined by HPLC, presented higher values in all samples from 2020 compared to 2019, and the same was observed for esterified catechins. The epigallocatechin-3-gallate content was also higher in all samples from 2020 (214.52–240.16 mg/g DE) compared to 2019 (140.91–210.83 mg/g DE). Regarding caffeine content (12.86–20.45 mg/g DE in 2019 and 13.19–29.35 mg/g DE in 2020), the samples from April and June exhibited similar values in both years. In general, green tea samples exhibited better results in 2020 than in 2019, with the exception of FIC activity, while the varied TP and TF contents in certain months reflect the impact of climatic variation on tea quality.