Influence of different coffee drink preparations on ochratoxin A content and evaluation of the antioxidant activity and caffeine variations (original) (raw)
Related papers
2007
Ochratoxin A is an important mycotoxin that can enter the human food chain in cereals, wine, coffee, spices, beer, cocoa, dried fruits, and pork meats. Coffee is one of the most common beverages and, consequently, it has a potential risk factor for human health related to ochratoxin A exposure. In this study, coffee and corresponding byproducts from seven different geographic regions were investigated for ochratoxin A natural occurrence by HPLC-FLD, nutritional characterization, and antioxidant activities by spectrophotometric assay. The research focused on composition changes in coffee during the processing step "from field to cup". Costa Rica and Indian green coffees were the most contaminated samples, with 13 and 11 µg/kg, respectively, while the Ethiopian coffee was the least contaminated, with 3.8 µg/kg of ochratoxin A. The reduction of ochratoxin A contamination during the roasting step was comparable for any samples that were considered under the recommended level of 4 µg/kg. Total dietary fibers ranged from 58.7% for Vietnam and 48.6% for Ivory Coast in green coffees and ranged from 58.6% for Costa Rica to 61.2% for India in roasted coffee. Coffee silverskin byproduct obtained from Ivory Coast was the highest, with 69.2 and 64.2% of insoluble dietary fibers, respectively.
Ochratoxin A in commercial soluble coffee and coffee substitutes
Food Research International, 2014
Sensory profi les of commercial coffee substitutes were determined and their possible interdependences with antioxidant characteristics (FRAP, DPPH, ABTS, and CUPRAC), total polyphenol content, and colour were investigated and compared to coffees. Statistically relevant relations were revealed between certain sensory attributes, colour, and antioxidant capacity. Sensory attributes show distinct patterns for coffees, their blends, and substitutes, but no signifi cant differences between substitutes from different raw materials were found, except for chicory. Although coffees have generally higher antioxidant capacities than their substitutes, these latter, especially chicory-based products, are also valuable antioxidant sources, as only half of them had signifi cantly lower polyphenol and antioxidant contents when compared to coffee. Principal component analysis was applied to reveal possible differentiation pattern between samples, based on both their sensory and antioxidant attributes.
Determination of Caffeine Content and Antioxidant Activity of Coffee
American Journal of Applied Chemistry, 2015
Attempt has been made to look into caffeine contents and antioxidant activity of coffee grown at Wembera, Goncha, Zegie, and Burie localities of NorthWest Ethiopia. The caffeine content of the extracts in % w/w has been found to be 1.53 ± 0.003 for Wembera coffee, 1.41 ± 0.040 for Goncha coffee, 1.29 ± 0.033 for Zegie coffee and 0.97 ± 0.049 for Burie coffee. The antioxidant activities of the coffee extracts were measured by using ferric reducing power assay and Rancimat assay. Ferric reducing power assay was used to measure the total antioxidant power of water soluble components of coffee and is expressed as ascorbic acid equivalent antioxidant capacity in milligram per gram of the dried coffee samples. The ferric reducing power values of the extracts were 9.532 ± 0.201, 9.159 ± 0.441, 8.955 ± 0.180, 6.751 ± 0.284 for Wembera, Burie, Goncha and Zegie coffees, respectively. The Rancimat assay was also used to measure antioxidant activity of lipid soluble portions of coffee extracts using sunflower oil as the oxidizable substrate. It was found that all the coffee extracts improved the oxidative stability of sunflower oil. The protection factors were 1.36 ± 0.027, 1.31 ± 0.027, 1.26 ± 0.069 and 1.17 ± 0.015 for Wembera, Burie, Goncha and Zegie coffees respectively. Based on these results, it is suggested that Wembera coffee has the higher caffeine content and antioxidant activities than Burie, Goncha and Zegie coffee varieties.
Protective effect of Yemeni green coffee powder against the oxidative stress induced by Ochratoxin A
Toxicology Reports, 2020
The current study focusses on knowing the antioxidant effects of green Yemeni coffee powder on reducing the oxidative stress that was induced by Ochratoxin A in kidney, liver and brain of rats. The grouping of female albino Wistar rats was into 5 groups (5 rats/group). Rats of Group 1 designated Vehicle Control (only water), Group2 (10 mg/kg Ochratoxin A); Group 3 designated Low dose (2000 mg/kg Coffee+10 mg/kg Ochratoxin A); Group 4 designated High dose (4000 mg/kg Coffee+10 mg/kg Ochratoxin A); Group 5 designated Coffee Control (1000 mg/kg Coffee) and orally administered with the above test materials repeatedly every day for 28 days. On termination of the study, liver, brain and kidney tissues were collected after dissection, oxidative stress biomarkers (Levels of Lipid Peroxidation and Reduced Glutathione, activities Superoxide Dismutase, Catalase and Glutathione Reductase enzymes) and histopathological studies were carried out. Treatment of Ochratoxin A alone (group 2 rats) significantly increased malondialdehyde content, catalase, and glutathione reductase activities with a decrease in the activity of superoxide dismutase enzyme and reduced glutathione level and in brain, kidney and liver. Whereas, low dose coffee (group 3) and high dose coffee (group 4) rats showed dosedependent increase in antioxidant and less histopathological alterations. Concomitant treatment of Yemeni green coffee powder and Ochratoxin A brought dose-dependent protective effects against oxidative stress which was induced using Ochratoxin A in liver, brain, and kidney tissues of female rats.
Food Additives & Contaminants: Part A, 2008
A rapid and reliable procedure has been developed for the determination of ochratoxin A (OTA) in 11 green and roasted coffee. The method consists of extraction of the sample with methanol-5% 12 aqueous sodium hydrogen carbonate/1%PEG8000-(20:80), followed by IAC clean up and finally, 13 HPLC determination with fluorimetric detection. Mean recoveries for green and roasted coffee 14 spiked at different levels ranging from 94 and 105 % were obtained. The limit of determination 15 (S/N= 3) was 0.032 ng/g and the precision (within-laboratory relative standard deviation) was 6%. 16 The method described has been used to assess the influence of roasting and different brewing 17 processes on OTA content in commercial lots of green and roasted coffee. The results provided 18 evidence that roasting led to a significant drop on OTA levels (65-100%). Also the way coffee is 19 prepared affects the OTA content: brewing using a moka express (Italian coffee) led to a significant 20 reduction of OTA concentration (50-75%) since hot water stays in contact with coffee for a short 21 time, on the contrary Turkish coffee making (infusion for about 10 min) cause poor reduction in 22 OTA 23
LWT - Food Science and Technology, 2004
Antioxidant and pro-oxidant properties of coffee can be affected by several factors such as coffee variety, roasting process, storage, etc. The aim of this study was to compare the antioxidant and pro-oxidant properties of coffee beverages obtained with conventional and torrefacto roasted coffee. Coffee variety influences on the antioxidant capacity of ground coffee. A100 roasted samples presented lower antioxidant capacity than Robusta varieties. This could be due to the higher percentage of chlorogenic acids in Robusta ground coffee than in Arabica. Beside, A100 samples presented the highest value of pro-oxidant activity because these samples presented less efficient antioxidants. In Torrefacto roast, the antioxidant capacity increased and redox potential decreased due to the formation of MRPs, which have reducing properties.
Study of Antioxidant Effects of Selected Types of Coffee
Folia Veterinaria, 2016
Coffee is a rich source of dietary antioxidants which protects the human body against the effects of dangerous free radicals. The aim of this study was to determine and compare the antioxidant activity, content of total phenols and flavonoids in selected types of coffee with respect to the way of their processing. The individual coffees were investigated with regard to their origin and composition. The antioxidant effects were determined by the 2,2-diphenyl-1-picryl-hydrazyl (DPPH) radical scavenging assay. The content of total phenols was analysed by the Folin-Ciocalteu method and the content of flavonoids in the coffee extracts was determined by a colorimetric method. The highest antioxidant activity was exhibited by the extract of unroasted ground 100 % green coffee
A Review on The Antioxidant Assays that can be Used to Determine Antioxidant Activity in Coffee
Caffeine is commonly found in coffee. Coffee is a chemically complex compound that includes substantial quantities of chlorogenic acid and caffeine. This review summarizes published research on quantifying antioxidant activity in coffee samples in vitro employing multiple methods such as FRAP, ORAC, ABTS, Hydroxyl Radical Scavenging assays. Caffeine is commonly found in coffee. Coffee is a chemically complex compound that includes substantial quantities of chlorogenic acid and caffeine.
Archivos latinoamericanos de nutrición, 2013
In the present study a simple and highly sensitive RP-HPLC method has been established for simultaneous determination of chlorogenic acid, caffeic acid, vanillic acid and caffeine in coffee samples. The method has been applied to eight different coffees available on the Romanian market which were previously analysed concerning the total polyphenols content and antioxidant capacity. Reduction of the DPPH radical was used to determine the antioxidant capacity of the coffee extracts while the total polyphenols content was determined by spectrophotometry (Folin Ciocalteu's method). The total polyphenols content ranged from 1.98 g GAE/100 g to 4.19 g GAE/100 g while the caffeine content ranged from 1.89 g/100 g to 3.05 g/100 g. A large variability was observed in chlorogenic acid content of the investigated coffee samples which ranged between 0.6 and 2.32 g/100 g.
Adding Adulterants to Coffee Reduces Bioactive Compound Levels and Antioxidant Activity
The present study aimed to evaluate the effect of coffee adulteration on antioxidant activity in vitro. Coffee beverages were adulterated with different concentrations of coffee hulls, coffee straw, and corn (0%, 10%, 20%, 30%, 40%, 50%, and 100%) and tested separately. Each coffee beverage was prepared according to the same methods in all of the treatments. Phenolic compound, caffeine, trigonelline, and chlorogenic acid levels were determined in the beverages. Antioxidant activity in vitro was evaluated using the DPPH radical scavenging activity, reducing power, iron chelating activity, and lipoperoxidation inhibition methods. Phenolic compound, caffeine, and chlorogenic acid levels of the samples decreased with increasing adulterant concentration. Adding adulterant reduced the antioxidant capacity tested using all of the methods. The results show that adding coffee hulls, coffee straw, and corn affect the antioxidant capacity of the coffee beverages, reducing protection against oxidative stress.