Caffeine Content Research Articles

Test of Level of Likes on Fermentation Length and Physical Quality Characteristics of Robusta Coffee After Storage

One of the stages in the wet processing of coffee that can affect its flavor is fermentation. Fermentation is the process of removing the mucilage layer that still adheres to the coffee beans, which results in a distinctive coffee aroma and reduces caffeine content, especially in robusta coffee. After the fermentation process, packaging and storage are carried out. Storage is the stage where raw coffee beans are kept to maintain their quality until the next process. This study aims to determine the effect of fermentation duration on panelists' preference levels and the impact of storage duration on the physical quality characteristics of robusta coffee. This research employs both quantitative and qualitative descriptive methods. The results show that storage duration does not affect the physical quality characteristics of robusta coffee beans. The moisture content parameter after storage was found to be 12.2%, the density parameter averaged 0.691 gr/ml, and the defect value parameter fell into grade 3. The study also shows that different fermentation durations do not significantly affect the panelists' preference levels, with an average score of 3-4,1.

Strigolactone enhances tea plant adaptation to drought and Phyllosticta theicola petch by regulating caffeine content via CsbHLH80

Strigolactones (SLs) play crucial roles in both plant growth and stress responses. However, their impact on the secondary metabolites of woody plants remains elusive. Here, we found that exogenous strigolactone analogue GR24 positively regulates tea plant flavor secondary metabolites, concurrently inhibiting caffeine biosynthesis and promoting the accumulation of caffeine catabolic pathway products. In this process, SL directly or indirectly inhibits the expression of CsSAMSs by inducing CsbHLH80, thereby reducing caffeine biosynthesis. Furthermore, CsbHLH80 enhances caffeine degradation, leading to increased allantoin. Under normal conditions, heightened allantoin reduces abscisic acid (ABA) accumulation. This inhibition reverses under drought stress. Increased ABA significantly enhances tea plant tolerance to both drought and Phyllosticta theicola Petch. In summary, this study offers novel insights for improving tea plant adaptation and quality in arid regions, particularly emphasizing the selection of stress-tolerant varieties and the refinement of production measures with a focus on high-quality production and environmentally friendly biological control methods.

Analysis of Caffeine, Tannin and Total Phenol Content of Tea Leaves from Sirah Kencong Blitar Plantation

Analysis of Caffeine, Tannin and Total Phenol Content of Tea Leaves from Sirah Kencong Blitar Plantation

Unveiling the Nutritional Profile and Safety of Coffee Pulp as a First Step in Its Valorization Strategy.

The coffee pulp, a significant by-product of coffee processing, is often discarded but has potential for recycling and high-value uses. This study aimed to investigate the chemical composition of two coffee pulp ingredients, a flour (CPF) and an aqueous extract (CPE), and conducted acute and sub-chronic toxicity assays to determine their safety. The proximate composition revealed the high fiber content of both ingredients; the CPF mainly contained insoluble fiber, while CPE consisted exclusively of soluble pectic polysaccharides. The CPF had higher concentrations of amino acids and a better balance of essential/non-essential amino acids, whereas the CPE exhibited higher concentrations of free amino acids, ensuring higher bioavailability. Both ingredients showed elevated mineral content, while heavy-metal concentrations remained within acceptable limits. This study established the bioactive potential of the CPF and the CPE, demonstrating the high content of caffeine and gallic, protocatechuic, and 4-caffeoylquinic acids. The toxicity studies revealed that the CPF and the CPE exhibited safety when orally administered to mice. Administered doses were non-toxic, as they did not induce lethality or adverse effects in the mice or produce significant histopathological or biochemical adverse changes. This study represents a first step in valorizing the CPF and the CPE as safe novel food ingredients with health benefits for functional and nutritional foods.

Studi Karakteristik Fisikokimia dan Organoleptik Bubuk Kopi dari Biji Cacat Hitam Kopi Robusta dengan Perbedaan Suhu Penyangraian

This research studied the effect of the level of black coffee bean defects and roasting temperature on the physicochemical content of coffee powder and the organoleptic content of robusta coffee brewing. This research used a factorial Randomized Complete Block Design (RCBD) with two replications. Parameters in this study, namely moisture content, ash content, pH, caffeine content, color intensity, and sensory. Data analysis in this research used ANOVA at the 5% level and a DMRT follow-up test. The research result show that there is an interaction between the treatment of the type of defective beans and roasting temperature on moisture content, ash, pH, color intensity of robusta coffee powder, and organoleptic brewing of robusta coffee. Different types of defective beans significantly affected the moisture content, ash, pH, caffeine, and color intensity of robusta coffee powder, while differences in roasting temperature significantly affected the water content, ash, pH, caffeine, and color intensity of robusta coffee powder. The best treatment for all physicochemical and organoleptic parameters is partially black beans with a roasting temperature of 180 °C.

Improved Functions of Fermented Coffee by Lactic Acid Bacteria

Coffee is one of the most popular beverages in the world, and at present, specialty coffees are developing for better tastes, flavors, or functions. Fermented coffees also reflect this trend and some brands are commercialized. Unlike general fermented coffees, we tried to ferment coffee extract with several lactic acid bacteria. Finally, we selected three strains that persisted in the coffee extract, and show strong antimicrobial activity, for the fermentation starters. The strains were identified as Pediococcus pentosaceus (KNUT 0384), Lacticaseibacillus paracasei (CJNU 1840), and Lactiplantibacillus plantarum (CJNU 0441) based on 16S rRNA gene sequences. During the fermentation process, the total acidities (p < 0.05 vs. the control, non-fermented coffee extract) and cell masses increased, which indicates that the bacteria metabolized properly in the extract. Furthermore, the fermented coffee extracts showed increased antimicrobial activities against Listeria monocytogenes (p < 0.05 vs. the control) and Streptococcus mutans (p < 0.05 vs. the control), increased anti-oxidative activities (p < 0.05 vs. the control, except for the KNUT 0384 sample), decreased caffeine content (p < 0.05 vs. the control, except for the KNUT 0384 sample), and increased chlorogenic acid content (p < 0.05 vs. the control). Taken together, the fermented coffee extracts with the selected lactic acid bacteria could be specialty coffees where several functions are improved when compared with a control coffee extract.

Effect of Nano Urea on Leaf Nutrients and Some Quality Parameters of Tea (Camellia sinensis (L) O. Kuntze)

Some important parameters of tea on mature plants of TV 23 clone were studied after application of Nano-urea as foliar spray at Experimental Garden for Plantation Crops, Assam Agricultural University, Jorhat during the period 2021-2022. The usage of "Nano Urea" (Liquid), a novel product created and patented by Indian Farmers Fertilizer Cooperative Limited (IFFCO), is projected to replace the use of urea granules, one of the most widely used fertilizers in the world. Leaf nutrients i.e., nitrogen, phosphorus, potassium and quality parameters i.e., Caffeine, polyphenol were observed after application of nano urea. Leaf nitrogen, leaf phosphorus and leaf potassium were found to be increased with the application of higher dose of Nano Urea. Leaf nitrogen was observed maximum (4.57%) in the plot where 0.4% Nano-urea applied in three sprays. Total phosphorus content of leaf was found to be the highest in treatment T7(0.423%) the lowest was observed in treatment T0 (0.370%). Total potassium content of leaf was the highest in treatment T7 (2.517%) and lowest K2O content was observed in treatment T0 (2.013%) which was a control. In quality parameters, it was found that application of Nano Urea showed significant impact on the total caffeine content of tea leaf. The highest value of caffeine was found in treatment T7 (3.233%) and lowest was found in treatment T0 (3.10%) (control).

Assemble and validation of a simulated device of human exhaled breath aerosols for screening of illicit drug abuse by HPLC-TQ-MS/MS detection

Collecting exhaled breath aerosols (EBA) as a sample has a great potential to monitoring illicit drug abuse due to advantages of simple, non-invasiveness and unrestricted sampling. However, scarcity of positive samples has cramped development of more efficient techniques for monitoring illicit drug abuse in EBA. In this work, a simulated human exhaled breath aerosol (SHEBA) generating device based on Venturi jet principle was constructed by integrating nebulizing unit and collection unit to prepare positive EBAs. By means of ultra high-performance hyphenated with triple quadrupole tandem mass spectrometry (HPLC-TQ-MS/MS), using caffeine as a target drug, the device parameters were investigated by studying the effects of flow rates of nebulizing and auxiliary gases, drug concentration and etc., the performance was further validated by commonly abused drugs such as amphetamines (AMP, MAMP, MDA and MDMA). Electret material as adsorbent was used to collect SHEBAs generated by the device, achieving HPLC-TQ-MS/MS detection of the captured drugs at 40.0–2000.0 pg/filter. By this way, caffeine content in EBAs from six volunteers was successfully detected in the range of 51.6 ± 6.8–708 ± 51 pg/filter after drinking the caffeinated beverage. These validation experiments proved that SHEBA generating device could not only meet to the requirement of EBA analysis for illicit drug abuse at trace levels, but also provide the correction factors to calibrate the lower detection value caused by incomplete material adsorption.

The Influence of Maceration and Flavoring on the Composition and Health-Promoting Properties of Roasted Coffee.

Over the years, many methods of refining green beans have been developed, including maceration aimed at enriching the coffee aroma and improving the overall quality. This study aimed to evaluate the influence of different methods of maceration (fruit and wine) and the addition of food flavors to coffee beans on antioxidant activity, caffeine, phenolic and organic acid content, as well as health-promoting properties. This research showed that the use of the maceration in melon and apple fruit pulp (100 g of fruit pulp per 100 g of green coffee, incubated for 24 h, coffee roasting at 230 °C, control trial roasted coffee) ensured the highest polyphenol (hydroxycinnamic acids and their esters-chlorogenic acids) content (in melon pulp-13.56 g/100 g d.b. (dry bean); in apple pulp-13.22 g/100 g d.b., p < 0.05 (one-way ANOVA)) and antioxidant activity. Melon (92.11%, IC50 = 3.80 mg/mL extract) and apple (84.55%, IC50 = 4.14 mg/mL) showed the highest α-amylase (enzyme concentration 10 μmol/mL) inhibition activity (0.5 mg/mL for both fruits). The addition of food flavors reduced the total content of chlorogenic acids to the range of 4.64 to 6.48 g/100 g d.b. and increased the content of acrylamide and 5-HMF, which positively correlated with a low antioxidant potential compared to the macerated samples and the control. Studies have shown that coffee macerated in the pulp of melon and apple fruit, due to its great potential to inhibit α-amylase in vivo, may have a preventive effect on type II diabetes. This study complements the current knowledge on the potential health-promoting properties of coffee flavored using different methods; further research should include more advanced models for testing these health-promoting properties. Statistical analysis was based on the determination of the average values of six measurements and their standard deviation, as well as on the one-way ANOVA (analysis of variation) and the Pearson correlation coefficient, using Statistic 10.0 software. The significance was defined at p ≤ 0.05.

Study on the Effect of Sooty Mould Disease in Tea Plants.

Sooty mould (SM) disease affects the growth, development and metabolism of plants and reduces the commodity and economic value of crops. SM disease is one of the important leaf diseases in tea plants. Nonetheless, studies on the effect of SM disease in tea plants are rare. Herein, we found that SM disease disrupted the cell morphology and structure and reduced the contents of caffeine, theanine, and catechins in the mature leaves of tea plants. Transcriptome analysis revealed that SM disease inhibited the biosynthesis of lignin, chlorophyll, catechin, caffeine, and theanine and affected the plant-pathogen interactions in the mature leaves of tea plants by downregulating gene expression. In addition, two fungal isolates, MTzyqA and MTzyqB, were obtained from the mature leaves of diseased tea plants. These strains were identified as Cladosporium pseudocladosporioides by mulitgene phylogenetic analysis, and they grew epiphytically on the leaves of tea plants. The biocontrol bacteria JT68, ZGT5, and BX1 had obvious inhibitory effect on MTzyqA and MTzyqB. These results provide a basis for understanding the effect of SM disease in tea plants.

Ilex paraguariensis Extracts: A Source of Bioelements and Biologically Active Compounds for Food Supplements

Ilex paraguariensis, commonly known as yerba mate, is a plant belonging to the holly genus Ilex and the Aquifoliaceae family, indigenous to South America, and is used for the production of yerba mate. Yerba mate is renowned for its abundance of essential nutrients and bioactive compounds. Based on test results, it can be assumed that the selection of raw material for the preparation of extracts as well as the extraction method significantly influence the final content of biologically active compounds in the extracts. Consequently, this variability impacts the ultimate concentration of biologically active substances within the end product, potentially influencing human consumption. The present study aimed to quantify and compare the content of selected biological active compounds in supplements and products containing I. paraguariensis extracts, along with organic yerba mate dried through a smoke-free process, available in the European market (P-1–P-10). The evaluation focused on antioxidant substances such as neochlorogenic acid, chlorogenic acid, cryptochlorogenic acid, 4-feruloylquinic acid, isochlorogenic acid, rutoside astragalin, and caffeine. Additionally, the concentration of specific macro and trace elements was ascertained. The antioxidant compound makeup differs between methanol-extracted samples and aqueous extracts. In both cases, methanol extracts, particularly those in instant and traditional herb forms, showed the highest content of organic compounds with antioxidant properties (such as phenolic compounds and caffeine). The highest content of chlorogenic acid was detected in both methanol (14.7412 mg/g d.w.) and water (8.3120 mg/g d.w.) extracts in product P-4. The caffeic acid content ranged from 0.1491 mg/g d.w. to 1.7938 mg/g d.w. in methanol extracts and from 0.0760 mg/g d.w. to 0.4892 mg/g d.w. in water extracts. The neochlorogenic acid content ranged from 2.6869 to 23.9750 mg/g d.w. in ethanol extracts and from 0.4529 to 10.2299 mg/g d.w. in water extracts. Therefore, the traditional preparation of yerba mate as a water infusion does not fully exploit the raw material’s potential. Among the tested products, only the dietary supplement in capsule form contained protocatechuic acid, which was not present in any other tested products. Conversely, compounds characteristic of yerba mate found in other preparations were absent in this supplement. The caffeine content was also the lowest in this product. The determined content of active substances did not consistently match the declarations made by producers if stated on the packaging.

Genetic parameters and chemical characterization of conilon coffee accessions under irrigation in the Cerrado

The objective of this study was to identify the genetic, phenotypic and environmental parameters related to chemical compounds associated with beverage quality in a conilon coffee collection, grown in an irrigated system, in the Cerrado. The experiment was carried out at Embrapa Cerrados using green grains harvested in two years from 84 genotypes of the cultivar Robusta Tropical. Caffeine content, protein, ether extract, total soluble solids, pH and titratable acidity were evaluated. The data were subjected to analysis of variance. Significant differences were observed at 1% probability among accessions for all evaluated chemical characteristics in both harvest years. The high heritability, genetic coefficients of variation and selective accuracy reveal the potential for achieving genetic gains via the selection of genotypes adapted to the irrigated system in the Cerrado combined with high beverage quality.

Physicochemical and Biochemical Changes in Cocoa during the Fermentation Step

The physicochemical and biochemical changes during the fermentation of four clones and two native varieties of Theobroma cacao L. were studied. Fermentation was performed in traditional wood cubes. During fermentation, the cotyledon pH decreased, and the temperature increased to more than 10 °C above the ambient temperature (47 °C). The fermentation index (FI) increased in the clones C1, C4, C8, C9, and Guayaquil (G) to close to one at 120 h of fermentation. For the FI of the cocoa Criollo (Cr), a value of 2.5 was proposed according to the spectrophotometric scan performance. The total polyphenol content increased in all the samples from 21 (C8) to 70 (Cr) % in a comparison of the TPC at T0 and T120, respectively. The total flavonoid content increased from 16 (C8) to 51% in Guayaquil (G) during the fermentation period. In the case of the methylxanthines, such as theobromine and caffeine, both quantities decreased. The theobromine content decreased in all the samples from 6 (G) to 31% (C8). The caffeine content decreased in all the samples from 3% in Cr to 25% in C1 and G after fermentation. The antioxidant capability did not change after 120 h of fermentation, and the amount of methylxanthines did not affect the antioxidant potential of the fermented cocoa. The FTIR scan of the fat-free cocoa showed significant differences between the unfermented and fermented beans, and several peaks assigned to carbohydrates and proteins decreased.

Impact of Cold Atmospheric Plasma Pretreatment on the Recovery of Phenolic Antioxidants from Spent Coffee Grounds

In the present study, cold atmospheric plasma (CAP) was employed as a pretreatment method for the extraction of phenolic compounds from spent coffee grounds (SCGs). The impact of CAP treatment conditions, i.e., thickness of the SCGs layer (mm), distance between the plasma source and the SCGs layer (mm) and duration of CAP treatment (min), on the total phenol content, in vitro antioxidant activity, as well as caffeine and chlorogenic acid content of SCGs, was investigated. The process parameters were optimized with the aid of response surface methodology (RSM). After optimizing the CAP pretreatment conditions, the CAP-treated SCGs were subjected to ultrasound-assisted extraction using ethanol as the extraction solvent. The optimum conditions for CAP treatment identified, i.e., thickness, 1 mm; distance, 16 mm; and duration, 15 min, led to a significant enhancement in the recovery of bioactive compounds from SCGs compared to those obtained from untreated SCGs. Total phenolic content and antioxidant activity significantly increased (i.e., TPC from 19.0 ± 0.7 to 24.9 ± 1.4 mg GAE/100 g dry SCGs, ADPPH from 106.7 ± 5.01 to 112.3 ± 4.3 μmol Trolox/100 g dry SCGs, AABTS from 106.7 ± 5.01 to 197.6 ± 5.8 μmol Trolox/100 g dry SCGs, ACUPRAC from 17938 ± 157 to 18299 ± 615 μmol Trolox/100 g dry SCGs). A significant increase in caffeine content from 799.1 ± 65.1 mg to 1064 ± 25 mg/100 g dry SCGs and chlorogenic acid content from 79.7 ± 15.3 mg to 111.3 ± 3.3 mg/100 g dry SCGs, was also observed. Overall, CAP pre-treatment can be used to enhance the recovery of bioactive compounds from SCGs.

Valorization of faba bean peels for fungal tannase production and its application in coffee tannin removal

This study describes the optimization of the production conditions of Penicillium commune tannase on unutilized food waste, green bean peels, using the central composite of the response surface methodology. It also focuses on applying purified tannase to reduce tannins in coffee. The proposed design recommended a temperature of 29.07 °C, pH of 6.74, a tannin level of 6.76%, and 3.31% bean peels for maximum tannase production (313.40 U/g/min) by solid-state fermentation. This waste can be used as a sustainable and low-cost substrate for tannase enhancement by ≈5 folds. Applying purified tannase in instant coffee beverage resulted in a ≈ 23% reduction in tannins and a ≈ 16% increase in reducing sugars, with no significant changes in caffeine and phenolic compound contents. Tannase had a detrimental effect on the volume and stability of the coffee foam. This study will pave the way for tannase industrial production and its promising use in low-bitter coffee production.

Biochemical composition and volatile profile analysis of three varieties of Coffea arabica and their correlation with the microclimate of Mount Tangkuban Perahu, West Java, Indonesia

Abstract. Firnabillah RA, Mustari E, Marwani E. 2024. Biochemical composition and volatile profile analysis of three varieties of Coffea arabica and their correlation with the microclimate of Mount Tangkuban Perahu, West Java, Indonesia. Biodiversitas 25: 3264-3276. The quality of coffee is determined by various biochemical compounds, including chlorogenic acid, caffeine, trigonelline, sucrose, and oil, as well as the volatile metabolite profile in coffee beans. Genetic factors and environmental conditions at the coffee cultivation site influence the composition of these compounds. This study aimed to analyze the biochemical composition and volatile profile of various coffee samples, including Ateng, Tim-Tim, and Sigarar Utang, and investigate their correlation with microclimate factors. Different analytical methods were used to examine the green beans, including High-Performance Liquid Chromatography-Mass Spectrometry (HPLC-MS) for caffeine, chlorogenic acids, sucrose, and trigonelline, Soxhlet methods for oil content determination, and Gas Chromatography-Mass Spectrometry (GC-MS) for volatile compound analysis. The results showed distinct biochemical components and metabolite profiles among the three arabica coffee varieties. The Ateng variety had the highest concentrations of chlorogenic acid, while the Tim-Tim variety had the lowest content of these compounds. Trigonelline and caffeine content was similar across all varieties. Sucrose content was highest in the Sigarar Utang variety, while oil content was higher in the Ateng and Tim-Tim varieties compared to Sigarar Utang. Principal Component Analysis (PCA) showed significant metabolite variation among the three varieties, with PC1 and PC2 accounting for 69.2% of the variance. Furthermore, Partial Least Squares-Discriminant Analysis (PLS-DA) successfully distinguished the three varieties and identified potential biomarker compounds for classification. Additionally, the study discovered that the environmental factor, specifically light intensity affected the sucrose and oil compounds in arabica green beans coffee. The study concluded that the three varieties' biochemical composition and volatile metabolites differed. Certain compounds were found to correlate with measured microclimatic factor.

Extrusion pretreatment of green Arabica coffee beans for lipid enhance extraction

Brazil is the world's largest producer and exporter of green coffee. Coffee beans have intrinsic and extrinsic defects that affect their chemical composition and the consumer perception of the beverage. The aim of this work is to evaluate the impact of extrusion process in green Arabica healthy and defective coffee beans in order to increase oil yield. The chromatographic analyses of the non-processed beans showed that caffeine, diterpenes and serotonin amides did not vary between the samples (p<0.05), while moisture and ash content varied significantly. The extrusion process followed by Soxhlet was optimized using central composite rotation design (CCRD) 22. Extrusion at the point selected as optimal (68ºC and 60 rpm) proved to be efficient when applied in combination with Soxhlet extraction, causing an increase of 61–81 % of oil yield (15.29 ± 0.42 % from defective beans and 16.42 ± 0.63 % from healthy beans), while its use combined with pressing (6.99 ± 0.08 %) was not significant compared to Soxhlet extraction alone (9.05 ± 0.24 %). Caffeine, diterpenes, serotonin amides and fatty acids methyl esters (FAMES) were analyzed in the oils where most of the fatty acids showed similar percentage values (p ≤ 0.05). The total diterpene content was higher in the extruded beans, while serotonin amides varied according to healthy and defective beans and pre-treatment (for defective grains), with defective grains showing consistently higher content compared to healthy grains (p ≥ 0.05). Caffeine content was similar between the healthy extruded, defective and defective extruded grains, with the lowest content in the healthy grain. It can be concluded that extrusion is a pre-treatment with a high impact in coffee oil yield. Green coffee oil is commercially explored by cosmetics and pharmaceutical industries due to its emollient and moisturizer properties. Besides, this oil protects skin against UV radiation. These properties are related to bioactive compounds present in the lipid fraction of coffee bean as diterpene esters, fatty acids and serotonin amides, which together justify this study.

Metabolic profiling reveal changes in shoots and roots of nitrogen-deficient tea plants (Camellia sinensis cv. Jinxuan)

Tea plants require high levels of nitrogen for optimal growth. However, delayed or insufficient nitrogen supply often induces nitrogen deficiency stress. This stress can adversely affect the plant's growth, development, and metabolic processes. Therefore, studying how tea plants respond to nitrogen deficiency conditions is crucial for enhancing our understanding and management of their growth environment. In this study, we utilized High-Performance Liquid Chromatography (HPLC), Gas Chromatography-Mass Spectrometry (GC–MS), and Ultra-Performance Liquid Chromatography-Tandem Mass Spectrometry (UPLC-MS) techniques to analyze the non-volatile and volatile components of both shoots and roots of the 'Jing Xuan (JX)' tea variety under nitrogen deprivation for 30 days (Nd). The results revealed that nitrogen deprivation led to a deceleration in shoot growth of 'JX', accompanied by reduced chlorophyll and water-soluble extract contents, with nitrogen accumulating predominantly in the roots. Significant decreases were observed in caffeine content in shoots and in the total amounts of theanine and catechins in both shoots and roots, while epigallocatechin gallate (EGCG) accumulation increased in shoots. Moreover, we identified 65 volatile components in shoots, including a notable decrease in floral and fruity compounds such as trans-β-Ionone, Geranylacetone, and α-Ionone. The biosynthesis of amino acids and phenylpropane metabolism are more active pathways under nitrogen stress. Nitrogen deficiency led to reduced levels of amino acids, carboxylic acids, flavonoids, steroids, and their derivatives in roots, with the most notable decline observed in carboxylic acids, typified by Leucine, l-Aspartate, and l-histidine. In contrast, shoots accumulate carbohydrates and phenolic compounds, mainly sucrose. Additionally, metabolites such as Myristic acid and 3-Dehydroshikimate could be a critical indicator of stress levels. These findings enhance our understanding of tea plant growth and metabolism under nitrogen deficiency, providing valuable insights for breeding nitrogen-efficient tea varieties.

Effects of different decaffeination methods on caffeine contents, physicochemical, and sensory properties of coffee

Abstract Coffee consumption could provide various benefits for human health, but also could contribute to several health problems. The growing trend of coffee consumption has created a rising demand for decaffeinated coffee that is safe for consumers with low caffeine tolerance. Decaffeination process, however, can result in the alteration of several properties of coffee which affect overall coffee taste. This review discussed current decaffeination methods such as water decaffeination, solvent decaffeination, supercritical decaffeination, and biodecaffeination which includes their mechanisms, benefits, and drawbacks as well as their effect in the physicochemical and sensory characteristics of coffee. Solvent decaffeination has showed potential improvements in the future such as the incorporation of membrane and ultrasonic technology. In addition, the mathematical model for caffeine diffusion has been arranged according to Fick’s second law of diffusion, based upon spherical and rectangular coordinates with several assumptions. Further research should be aimed to maintain the properties of coffee after decaffeination process. Furthermore, utilizing new solvents that are safe and non-toxic will potentially be favorable research in the development of decaffeination methods in the future.

Optimizing Ultrasonic‐Assisted Extraction for Enhanced Yield of Phenolic Compounds and Antioxidant Activity in Cold Brew Coffee

ABSTRACTThis study aimed to identify the best conditions for ultrasonic‐assisted extraction (UAE) of DPPH and phenolic compounds from cold brew coffee using Box‐Behnken Design (BBD) and Response Surface Methodology (RSM). It explored the effects of solid‐liquid ratio (5%–15%), extraction time (40–50 min), and ultrasonic power (70%–80%) on these compounds, finding that all factors significantly influenced the outcomes. Statistical analysis showed the data fit a quadratic polynomial model well, with R2 values of 0.9981 for phenolic compounds and 0.9799 for DPPH radicals. Using 3D surface and contour plots from these models, the optimal extraction conditions for these compounds from cold brew coffee were determined. The highest yields of total phenolic compounds and DPPH radical were obtained when samples were extracted at a 10% solid–liquid ratio, 45 min extraction time, and 75% ultrasonic power. Under these optimal conditions, total phenolic compounds and DPPH radical were 64.10 ± 0.31 gGAE/mL and 61.90 ± 0.14%, respectively, with a maximum caffeine content of 213.13 ± 0.23 mg/L. Gamma irradiation at kGy also reduced cold brew coffee's microbial content. This research may be a new alternative for producing cold brew coffee that will save time and help extend the shelf life.