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A special issue of Molecules (ISSN 1420-3049). This special issue belongs to the section "Food Chemistry".

Deadline for manuscript submissions: closed (30 June 2022) | Viewed by 52962

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Dr. Francesca Masino

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Department of Life Sciences, University of Modena and Reggio Emilia, 42122 Reggio Emilia, Italy
Interests: food; food safety; food contaminants; food quality; functional foods; natural products; sensory analysis; color of food; food innovative technology; enhancement of food waste and byproducts of the agrifood chain; recovery of interesting molecules by technological processes and their use for different new industrial applications or new formulations (ingredients, biogas, biopolymers formulations); waste management; circulary economy in agrifood
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Dear colleagues,

Coffee, together with tea, is the most widely consumed beverage in the world, both having been consumed for thousands of years for their alluring flavors and health benefits. Coffee contains several nutrients such as sugars, proteins, and lipids, as well as other bioactive compounds, including amino acids, caffeine, trigonelline, chlorogenic acids, and other phenolics, particularly flavonoids and phenolic acids. These are in great abundance in both tea and coffee and contribute a lot to their flavor and health properties. In addition, a considerable amount of volatiles is included. For this reason, coffee’s characterization and different species are studied continuously, also in relation to postharvest processing carried out, or roasting processes that aim to preserve the integrity of these compounds. Different studies regard sensory analysis and consumer acceptance. In addition, in recent years, a great deal of interest is turning to byproducts and waste, which are also themselves sources of sugars, proteins, lipids, and other bioactive compounds. For example, spent coffee grounds (SCG), the solid residue obtained after beverage preparation, is the main coffee industry residue and exceeds a worldwide production of 6 million tons per year.

Some attempts for a SCG second life have been made, e.g., biofuel for industrial boilers due to its high calorific power, source of fatty acids for biodiesel production, polysaccharides with immunostimulatory activity, antioxidant material, substrates for mushroom cultivation, and sources for preparation of new beverage formulations.

This Special Issue aims to attract contributions on:

1) All technology aspects of coffee production and their impact on coffee chemistry, nutritional and sensory quality, and consumer acceptance;

2) Study of byproduct valorization of coffee, potentialities, and perspectives further with a view to the actual topic of waste management, advocating the circular economy.

Dr. Francesca Masino
Guest Editor

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Keywords

Chemical and physical analysis
Sensory study and consumer science
Volatile compounds
Polyphenol preservation
Coffee and health
Coffee quality
Biocompounds extraction
Recover of nutrients
Byproducts
Waste management

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Chemistry of Tea and Coffee—2nd Edition in Molecules (5 articles)

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15 pages, 2768 KiB

Open AccessArticle

A Comparative Study for Nutritional and Phytochemical Profiling of Coffea arabica (C. arabica) from Different Origins and Their Antioxidant Potential and Molecular Docking

by Akhtar Ali, Hafza Fasiha Zahid, Jeremy J. Cottrell and Frank R. Dunshea

Molecules 2022, 27(16), 5126; https://doi.org/10.3390/molecules27165126 - 11 Aug 2022

Cited by 25 | Viewed by 5161

Abstract

Coffee is the most widely used beverage globally and contains many bioactive compounds, including phenolic compounds, alkaloids, triterpenes, organic acids, amino acids, hormones, and fatty acids. The main objective of this study was the comparative profiling of Australian, Colombian, Ethiopian, and Peruvian C. arabica using LC-ESI-QTOF-MS/MS. In this study, we tentatively identified 136 bioactive metabolites, including five (05) organic acids, six (06) alkaloids, three (03) amino acids (l-phenylalanine, l-tyrosine, and l-pyroglutamic acid), two (02) hormones (melatonin and serotonin), two fatty acids, one (01) furopyrans (goniothalenol), one (01) carotenoid (crocetin), three (03) terpenoids, thirty-eight (38) phenolic acids, forty-one (41) flavonoids, five (05) stilbenes, three (03) lignans and twenty-three (23) other polyphenols in C. arabica. The highest TPC value (17.74 ± 0.32 mg GAE/g) was measured in Colombian coffee while the lowest TPC value (10.24 ± 0.73 mg GAE/g) was in Peruvian coffee. Colombian coffee has a higher antioxidant potential than other studied coffee samples. A total of nineteen phenolic metabolites were mapped through LC-MS/MS. Quinic acid derivatives were quantified in higher concentrations than other metabolites. Furthermore, molecular docking predicted that chlorogenic acid is a main bioactive compound that contributes to anti-Alzheimer and anti-diabetic activities of C. arabica. The obtained results indicate that C. arabica contains a vast number of bioactive compounds which have potential health benefits. Furthermore, research could be conducted to validate the effect of these metabolites on the flavor profile of coffee beverages. Full article

(This article belongs to the Special Issue Chemistry of Tea and Coffee)

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22 pages, 8686 KiB

Open AccessArticle

Quantification of Spent Coffee Ground Extracts by Roast and Brew Method, and Their Utility in a Green Synthesis of Gold and Silver Nanoparticles

by Brian G. Yust, Niny Z. Rao, Evan T. Schwarzmann and Madisyn H. Peoples

Molecules 2022, 27(16), 5124; https://doi.org/10.3390/molecules27165124 - 11 Aug 2022

Cited by 6 | Viewed by 2819

Abstract

Nanotechnology has become increasingly important in modern society, and nanoparticles are routinely used in many areas of technology, industry, and commercial products. Many species of nanoparticle (NP) are typically synthesized using toxic or hazardous chemicals, making these methods less environmentally friendly. Consequently, there has been growing interest in green synthesis methods, which avoid unnecessary exposure to toxic chemicals and reduce harmful waste. Synthesis methods which utilize food waste products are particularly attractive because they add value and a secondary use for material which would otherwise be disposed of. Here, we show that spent coffee grounds (SCGs) that have already been used once in coffee brewing can be easily used to synthesize gold and silver NPs. SCGs derived from medium and dark roasts of the same bean source were acquired after brewing coffee by hot brew, cold brew, and espresso techniques. The total antioxidant activity (TAC) and total caffeoylquinic acid (CQA) of the aqueous SCG extracts were investigated, showing that hot brew SCGs had the highest CQA and TAC levels, while espresso SCGs had the lowest. SCG extract proved effective as a reducing agent in synthesizing gold and silver NPs regardless of roast or initial brew method. Full article

(This article belongs to the Special Issue Chemistry of Tea and Coffee)

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12 pages, 1998 KiB

Open AccessArticle

Characterization of Roasting Time on Sensory Quality, Color, Taste, and Nonvolatile Compounds of Yuan An Yellow Tea

by Fei Ye, Xiaoyan Qiao, Anhui Gui, Panpan Liu, Shengpeng Wang, Xueping Wang, Jin Teng, Lin Zheng, Lin Feng, Hanshan Han, Binghua Zhang, Xun Chen, Zhiming Gao, Shiwei Gao and Pengcheng Zheng

Molecules 2022, 27(13), 4119; https://doi.org/10.3390/molecules27134119 - 27 Jun 2022

Cited by 9 | Viewed by 2161

Abstract

Roasting is crucial for producing Yuan An yellow tea (YAYT) as it substantially affects sensory quality. However, the effect of roasting time on YAYT flavor quality is not clear. To investigate the effect of roasting time on the sensory qualities, chemical components, odor profiles, and metabolic profile of YAYTs produced with 13 min roasting, 16 min roasting, 19 min roasting, 22 min roasting, and 25 min roasting were determined. The YAYTs roasted for 22 min got higher sensory scores and better chemical qualities, such as the content of gallocatechin (GC), gallocatechin gallate (GCG), free amino acids, solutable sugar, meanwhile the lightness decreased, the hue of tea brew color (b) increased, which meant the tea brew got darker and yellower. YAYTs roasted for 22 min also increased the contents of key odorants, such as benzaldehyde, nonanal, β-cyclocitral, linalool, nerol, α-cedrol, β-ionone, limonene, 2-methylfuran, indole, and longiborneol. Moreover, non-targeted metabolomics identified up to 14 differentially expressed metabolites through pair-wise comparisons, such as flavonoids, phenolic acids, sucrose, and critical metabolites, which were the main components corresponding to YAYT roasted for 22 min. In summary, the current results provide scientific guidance for the production of high quality YAYT. Full article

(This article belongs to the Special Issue Chemistry of Tea and Coffee)

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24 pages, 3458 KiB

Open AccessArticle

Study on South African Indigenous Teas—Antioxidant Potential, Nutritional Content, and Hypoxia-Induced Cyclooxygenase Inhibition on U87 MG Cell Line

by Motlalepula Gilbert Matsabisa, Asis Bala, Satyajit Tripathy, Michelle Mogomane Digashu, Fanie Rautenbach, Barsha Dassarma, Joseph Omorogiuwa Erhabor, Fernao Castro Braga, Pulok Kumar Mukherjee, Minke Tang and Youngmin Kang

Molecules 2022, 27(11), 3505; https://doi.org/10.3390/molecules27113505 - 30 May 2022

Cited by 2 | Viewed by 2404

Abstract

Background: This study comparatively assessed seven indigenous traditional tea plants on several attributes that included antioxidant, nutritional, caffeine contents, and cyclooxygenase activity. Methodology: Nutritional content of all tea plants were determined for energy, fat, carbohydrates, total sugars, dietary fiber and amino acids. Antioxidant potential and the antioxidant potentiating secondary metabolites were also measured and compared. Further, we investigated the tea plants for any role they would have on cyclooxygenase (COX) activity on cobalt chloride (CoCl₂) induced human glioma cell lines (U87MG). Results: The tea plants were found non-cytotoxic at concentrations tested against the human Chang liver and HeK 293 kidney cells and were found to be naturally caffeine free. The lowest and highest extraction yield among the tea plants was 7.1% for B. saligna and 15.48% for L. scaberrimma respectively. On average, the flavonol content was 12 to 8 QE/g, ORAC 800 µmol TE/g, TEAC 150 µmol TE/g, FRAP 155 µmol AAE/g, polyphenols 40 mg GAE/g, flavanols 0.35 mg CE/g, flavonols 12 mg QE/g and total flavonoid content (TFC) 180 µg QE/mg. The COX activity has been found to be inhibited by a dose-dependent manner by L. scaberrimma, B. saligna and L. javanica. Conclusion: The results further support competitive value of tea plants and need for improved and further development. Full article

(This article belongs to the Special Issue Chemistry of Tea and Coffee)

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17 pages, 1788 KiB

Open AccessArticle

Optimization of Sensory Properties of Cold Brew Coffee Produced by Reduced Pressure Cycles and Its Physicochemical Characteristics

by Smaro Kyroglou, Rafailia Laskari and Patroklos Vareltzis

Molecules 2022, 27(9), 2971; https://doi.org/10.3390/molecules27092971 - 6 May 2022

Cited by 7 | Viewed by 3903

Abstract

The use of vacuum cycles for the cold extraction of coffee is a new process that leads to a significant reduction in process time of Cold Brew compared to conventional methods. This research aimed at specifying the necessary parameters for producing a consumer-accepted cold brew coffee by applying vacuum cycles. This was achieved by investigating the effect of the number of cycles and of the applied pressure (vacuum) on the physicochemical characteristics of the cold brew coffee, i.e., total dissolved solids (TDS%), pH, acidity, phenol and caffeine content and color. Furthermore, sensory evaluation took place by members of the Specialty Coffee Association of America (SCAA) to specify parameters such as coffee blend, coffee/water ratio, total water hardness and grind size and secondly to determine the optimal pressure and number of cycles for a tasty final beverage. The sensory and physiochemical characteristics of cold extraction coffee were investigated by Principal Component Analysis (PCA). It became evident that coffee extraction by applying two vacuum cycles at 205 mbar pressure produced the lowest intensity of physiochemical properties (caffeine, phenols, acidity, TDS% and pH), and the highest score of sensory characteristics (fragrance, body, acidity, flavor, balance, and aftertaste). Caffeine and phenol concentration of the optimal beverage were 26.66 ± 1.56 mg/g coffee and 23.36 ± 0.79 mg gallic acid/g coffee respectively. The physiochemical characteristics were also compared to a beverage of hot extraction of the same blend and ratio of coffee to water. Full article

(This article belongs to the Special Issue Chemistry of Tea and Coffee)

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12 pages, 1373 KiB

Open AccessArticle

Impact of Coffee Bean Roasting on the Content of Pyridines Determined by Analysis of Volatile Organic Compounds

by Marek Gancarz, Bohdan Dobrzański, Jr., Urszula Malaga-Toboła, Sylwester Tabor, Maciej Combrzyński, Daniel Ćwikła, Wacław Roman Strobel, Anna Oniszczuk, Hamed Karami, Yousef Darvishi, Alaksandra Żytek and Robert Rusinek

Molecules 2022, 27(5), 1559; https://doi.org/10.3390/molecules27051559 - 25 Feb 2022

Cited by 34 | Viewed by 6214

Abstract

The aim of the study was to analyze the process of roasting coffee beans in a convection–conduction roaster (CC) without a heat exchanger and a convection–conduction–radiation roaster (CCR) with a heat exchanger for determination of the aroma profile. The aroma profile was analyzed using the SPME/GC-MS technique, and an Agrinose electronic nose was used to determine the aroma profile intensity. Arabica coffee beans from five regions of the world, namely, Peru, Costa Rica, Ethiopia, Guatemala, and Brazil, were the research material. The chemometric analyses revealed the dominance of azines, alcohols, aldehydes, hydrazides, and acids in the coffee aroma profile. Their share distinguished the aroma profiles depending on the country of origin of the coffee beans. The high content of pyridine from the azine group was characteristic for the coffee roasting process in the convection–conduction roaster without a heat exchanger, which was shown by the PCA analysis. The increased content of pyridine resulted from the appearance of coal tar, especially in the CC roaster. Pyridine has an unpleasant and bitter plant-like odor, and its excess is detrimental to the human organism. The dominant and elevated content of pyridine is a defect of the coffee roasting process in the CC roaster compared to the process carried out in the CCR machine. The results obtained with the Agrinose showed that the CC roasting method had a significant effect on the sensor responses. The effect of coal tar on the coffee beans resulted in an undesirable aroma profile characterized by increased amounts of aromatic volatile compounds and higher responses of Agrinose sensors. Full article

(This article belongs to the Special Issue Chemistry of Tea and Coffee)

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18 pages, 2918 KiB

Open AccessArticle

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

by Danijela Šeremet, Patricia Fabečić, Aleksandra Vojvodić Cebin, Ana Mandura Jarić, Robert Pudić and Draženka Komes

Molecules 2022, 27(2), 448; https://doi.org/10.3390/molecules27020448 - 10 Jan 2022

Cited by 10 | Viewed by 3359

Abstract

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. Full article

(This article belongs to the Special Issue Chemistry of Tea and Coffee)

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15 pages, 1256 KiB

Open AccessArticle

Assessment of Concentrated Liquid Coffee Acceptance during Storage: Sensory and Physicochemical Perspective

by Mónica Quintero, Sebastián Velásquez, Julián Zapata, Carlos López and Luis Cisneros-Zevallos

Molecules 2021, 26(12), 3545; https://doi.org/10.3390/molecules26123545 - 10 Jun 2021

Cited by 6 | Viewed by 3504

Abstract

Concentrated liquid coffees (CLCs) refer to stored extracts stable at environmental temperature, used as ingredients in the retail market. Their low chemical stability affects the sensory profile. This study was performed in two CLCs, one without additives (BIB) and another with a mix of sodium benzoate and potassium sorbate additives (SD), stored at 25 °C for one year. Quantitative-Descriptive (QDA) and discriminant analyses permitted identifying the critical sensory attributes and their evolution over time. The concentrate without additives presented an acceptance limit of 196 days (evaluated at a 50% acceptance ratio), while the additives increased the shelf life up to 226 days (38.9% improvement). The rejection was related to a decreased aroma, increased acidity, and reduced bitterness. A bootstrapped feature selection version of Partial Least Square analysis further demonstrated that reactions of 5-caffeoylquinic acid (5CQA) and 3,5-dicaffeoylquinic acid (3,5diCQA) could cause changes in the aroma at the first degradation stage. In the following stages, changes in fructose and stearic acid contents, a key indicator of acceptance for both extracts possibly related to non-enzymatic reactions involving fructose and other compounds, might affect the bitterness and acidity. These results provided valuable information to understand flavor degradation in CLCs. Full article

(This article belongs to the Special Issue Chemistry of Tea and Coffee)

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13 pages, 1496 KiB

Open AccessArticle

Effect of Water Hardness on Catechin and Caffeine Content in Green Tea Infusions

by Mica Cabrera, Faizah Taher, Alendre Llantada, Quyen Do, Tyeshia Sapp and Monika Sommerhalter

Molecules 2021, 26(12), 3485; https://doi.org/10.3390/molecules26123485 - 8 Jun 2021

Cited by 15 | Viewed by 5592

Abstract

The health benefits of green tea are associated with its high catechin content. In scientific studies, green tea is often prepared with deionized water. However, casual consumers will simply use their local tap water, which differs in alkalinity and mineral content depending on the region. To assess the effect of water hardness on catechin and caffeine content, green tea infusions were prepared with synthetic freshwater in five different hardness levels, a sodium bicarbonate solution, a mineral salt solution, and deionized water. HPLC analysis was performed with a superficially porous pentafluorophenyl column. As water hardness increased, total catechin yield decreased. This was mostly due to the autoxidation of epigallocatechin (EGC) and epigallocatechin gallate (EGCG). Epicatechin (EC), epicatechin gallate (ECG), and caffeine showed greater chemical stability. Autoxidation was promoted by alkaline conditions and resulted in the browning of the green tea infusions. High levels of alkaline sodium bicarbonate found in hard water can render some tap waters unsuitable for green tea preparation. Full article

(This article belongs to the Special Issue Chemistry of Tea and Coffee)

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11 pages, 1658 KiB

Open AccessArticle

Decaffeination and Neuraminidase Inhibitory Activity of Arabica Green Coffee (Coffea arabica) Beans: Chlorogenic Acid as a Potential Bioactive Compound

by Muchtaridi Muchtaridi, Dwintha Lestari, Nur Kusaira Khairul Ikram, Amirah Mohd Gazzali, Maywan Hariono and Habibah A. Wahab

Molecules 2021, 26(11), 3402; https://doi.org/10.3390/molecules26113402 - 4 Jun 2021

Cited by 14 | Viewed by 5069

Abstract

Coffee has been studied for its health benefits, including prevention of several chronic diseases, such as type 2 diabetes mellitus, cancer, Parkinson’s, and liver diseases. Chlorogenic acid (CGA), an important component in coffee beans, was shown to possess antiviral activity against viruses. However, the presence of caffeine in coffee beans may also cause insomnia and stomach irritation, and increase heart rate and respiration rate. These unwanted effects may be reduced by decaffeination of green bean Arabica coffee (GBAC) by treatment with dichloromethane, followed by solid-phase extraction using methanol. In this study, the caffeine and chlorogenic acid (CGA) level in the coffee bean from three different areas in West Java, before and after decaffeination, was determined and validated using HPLC. The results showed that the levels of caffeine were reduced significantly, with an order as follows: Tasikmalaya (2.28% to 0.097% (97 ppm), Pangalengan (1.57% to 0.049% (495 ppm), and Garut (1.45% to 0.00002% (0.2 ppm). The CGA levels in the GBAC were also reduced as follows: Tasikmalaya (0.54% to 0.001% (118 ppm), Pangalengan (0.97% to 0.0047% (388 ppm)), and Garut (0.81% to 0.029% (282 ppm). The decaffeinated samples were then subjected to the H5N1 neuraminidase (NA) binding assay to determine its bioactivity as an anti-influenza agent. The results show that samples from Tasikmalaya, Pangalengan, and Garut possess NA inhibitory activity with IC₅₀ of 69.70, 75.23, and 55.74 μg/mL, respectively. The low level of caffeine with a higher level of CGA correlates with their higher levels of NA inhibitory, as shown in the Garut samples. Therefore, the level of caffeine and CGA influenced the level of NA inhibitory activity. This is supported by the validation of CGA-NA binding interaction via molecular docking and pharmacophore modeling; hence, CGA could potentially serve as a bioactive compound for neuraminidase activity in GBAC. Full article

(This article belongs to the Special Issue Chemistry of Tea and Coffee)

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14 pages, 5691 KiB

Open AccessArticle

Gibberellin Increases the Bud Yield and Theanine Accumulation in Camellia sinensis (L.) Kuntze

by Wei Li, Fen Xiang, Yi Su, Zhoufei Luo, Weigui Luo, Lingyun Zhou, Hongyan Liu and Langtao Xiao

Molecules 2021, 26(11), 3290; https://doi.org/10.3390/molecules26113290 - 29 May 2021

Cited by 15 | Viewed by 3424

Abstract

Tea (Camellia sinensis) is one of the most important cash crops in the world. Theanine, as an important amino acid component in tea, is a key quality index for excellent tea quality and high economic value. People increase theanine accumulation in tea mainly through the application of nitrogen fertilizer, shading and pruning. However, these methods are not effective. In this study, we treated tea buds with a 100 μM solution of GA₃ containing 1‰ tween-20, investigated the effects of GA₃ on theanine accumulation, bud yield, chlorophyll fluorescence parameters and expression level of theanine biosynthesis pathway genes in tea plant by qPCR, LC-MS/MS etc. Results showed that change trends of theanine and GA₃ was extremely positively correlated with each other. Exogenous GA₃ upregulated the expression level of theanine biosynthesis pathway genes, caused an increase of theanine content (mg·g^-1) by 27% in tea leaves compared with Mock, and accelerated the germination of buds and elongation of shoots, which lead to a significant increase of tea yield by 56% (w/w). Moreover, the decrease of chlorophyll contents, photochemical quenching coefficient (qP) and relative electron transport rate (rETR) under GA₃ treatment suggested that GA₃ reduced photosynthesis in the tender tea leaves, indicating that the decline of carbon assimilation in tea plants was conducive to the nitrogen metabolism, and it was beneficial to the accumulation of theanine. This study provided a new technical and theoretical support for the precise control of tea quality components and phenophase. Full article

(This article belongs to the Special Issue Chemistry of Tea and Coffee)

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Review

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23 pages, 1285 KiB

Open AccessReview

Coffee Chlorogenic Acids Incorporation for Bioactivity Enhancement of Foods: A Review

by Alexis Rojas-González, Claudia Yuritzi Figueroa-Hernández, Oscar González-Rios, Mirna Leonor Suárez-Quiroz, Rosa María González-Amaro, Zorba Josué Hernández-Estrada and Patricia Rayas-Duarte

Molecules 2022, 27(11), 3400; https://doi.org/10.3390/molecules27113400 - 25 May 2022

Cited by 55 | Viewed by 6830

Abstract

The demand of foods with high antioxidant capacity have increased and research on these foods continues to grow. This review is focused on chlorogenic acids (CGAs) from green coffee, which is the most abundant source. The main CGA in coffee is 5-O-caffeoylquinic acid (5-CQA). Coffee extracts are currently the most widely used source to enhance the antioxidant activity of foods. Due to the solubility of CGAs, their extraction is mainly performed with organic solvents. CGAs have been associated with health benefits, such as antioxidant, antiviral, antibacterial, anticancer, and anti-inflammatory activity, and others that reduce the risk of cardiovascular diseases, type 2 diabetes, and Alzheimer’s disease. However, the biological activities depend on the stability of CGAs, which are sensitive to pH, temperature, and light. The anti-inflammatory activity of 5-CQA is attributed to reducing the proinflammatory activity of cytokines. 5-CQA can negatively affect colon microbiota. An increase in anthocyanins and antioxidant activity was observed when CGAs extracts were added to different food matrices such as dairy products, coffee drinks, chocolate, and bakery products. The fortification of foods with coffee CGAs has the potential to improve the functionality of foods. Full article

(This article belongs to the Special Issue Chemistry of Tea and Coffee)

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