101,901 research outputs found
Optimization of espresso coffee extraction to lower the amount of coffee. S8-PO-09. Book of Abstracts, p. 168. 28th Conference ASIC 2021.
No full textRATIONALE
The espresso coffee (EC) quality is driven by several variables related to water, roasting profile, particle sizes and barista skills. Previous research has demonstrated that the sizes of coffee particles greatly affect on extraction kinetics. In fact, some studies highlighted that bigger particles could ease the percolation during the brewing process (Kuhn et al. 2017). However, the fine particles generate intensity of taste and can clog the filter baskets (Khamitova et al. 2020a). In this context, researchers have not studied yet in depth how different tools can be adjusted complementarily in coffee extraction, as how different filter baskets and perforated disc heights could be chosen according to the different particle sizes of ground coffee.
METHODS
The present project was based on the study and comparison of ECs prepared by decreasing the amount (from 14 to 12 g for double EC extraction) of specific particle sizes (from 200 to 1000 μm) of ground coffee in three variously designed filter baskets. The second part of the work was to investigate various heights of perforated disc under the shower (4-7 mm), and to prepare coffee with 14 and 12 g of ground coffee. The perforated disc is a perforated metal plate, assembled under the shower of each serving group of EC machine, which assures a homogeneous water diffusion over the coffee cake surface and adjusts the distance between the coffee cake and the shower. Thus, perforated disc can influence EC extraction, even if no studies have been reported yet; in fact, this parameter has been investigated for the first time by our research group (Khamitova et al. 2020b). ECs were analysed for the content of TDS, bioactive compounds, and organic acids with HPLC-VWD, while volatiles with HS-SPME-GC-MS.
RESULTS
Extracting with smaller particles escalates the quantity of bioactive compounds. The amount of caffeine per cup increased moving from 500–1000 μm to 200–300 μm particle size, both in Arabica and Robusta for all filter baskets. Using lower amount of ground coffee permitted to obtain the same extraction yield increasing the height of perforated disc. Keeping constant the volume of EC at various heights of perforated disc, the amount of bioactive compounds at 12 g were only around 9% lower than at 14 g.
CONCLUSIONS & PERSPECTIVES
The right implementation on EC machine of these tools, simple and feasible as they are, could lead to a more sustainable consumption of the beverage by reducing the amount of used R&G coffee and by producing lower spent coffee ground, while maintaining the same cup quality.
References:
• Kuhn et al. 2017 Journal of Food Engineering DOI: 10.1016/j.jfoodeng.2017.03.002.
• Khamitova et al. 2020a Food Chemistry DOI: 10.1016/j.foodchem.2020.126220.
• Khamitova et al. 2020b Food Research International DOI: 10.1016/j.foodres.2020.109220
Enhancing variables for Espresso Coffee extraction.
No full textEspresso coffee extraction is a very complex process due to the direct influence of temperature, pressure and particle size distribution. The grinding of coffee beans is crucial to obtain the optimal particle size for extracting excellent espresso coffee with tempting aroma, dense cream and mouthfeel flavour [1]. This research aims to assess the levels of volatiles and bioactive compounds such as caffeine, trigonelline, nicotinic acid, chlorogenic acids (CQAs) at different particle sizes (200-400 microns). Quantitative and qualitative analyses are carried out through HPLC-VWD and GCMS [2]. The espresso machine settings are maintained at 9 bar and 920C. Volatile compounds found in espresso coffee, determined in different particle sizes, were combined into family groups and their characteristics were identified [3, 4]. Extraction optimization have been developed by modifying the extraction variables
Water flow and transport in porous media for in-silico espresso coffee
No full textBrewing coffee is primarily considered an art rather than a business. Drinking coffee is a practice spread worldwide irrespective of race, age, and social extraction, making coffee the leading commodity in the fair trade movement. Its daily consumption has scientifically proven health benefits. Thus, such inter- esting features of coffee have stimulated a wide coffee-oriented scientific research addressing health, social and economical aspects. An important component of this research is an in-depth knowledge of the physico-chemical processes occurring in the coffee preparation. In this paper, we propose a math- ematical model for describing the percolation processes occurring during the espresso coffee extraction by exploiting fluid-dynamics components. The validity of this water percolation model into porous me- dia is demonstrated on an experimental basis, exploiting chemical laboratory analyses of espresso coffee samples extracted under different conditions
Effects of espresso machine variables on espresso coffee composition.
No full textIntroduction
Espresso machine variables have a large influence on the levels of bioactive components and on the aroma profile of espresso coffee (EC) [1]. The present contribution will report results of some years of research on this issue, studying electrical (Aurelia) and mechanical (Leva) pump equipped machine.
Body
This research project aims to assess the levels of aroma components and bioactive compounds such as chlorogenic acids (CGAs), caffeine, trigonelline and nicotinic acid, in different EC extraction conditions (temperature and pressure in two different EC machines). Quantitative analysis experiments were carried out on the two most common coffee cultivars, Arabica and Robusta. EC extraction times, kinetics of extraction and its dependence on water pressure and temperature were controlled during the analysis. Accordingly, the aroma sensory profile was analyzed, using a selected panel of trained sensory judges, in parallel with instrumental analysis. Results demonstrated that the espresso machine settings for the best EC were 9 bars and 88 or 92 °C. The two different espresso machines showed quite different extraction kinetics [2]. Regarding the peculiarity of the two different machines, the total concentration of three CGAs varied considerably, due to their physical parameters. The usual espresso machine settings (9 bars and 92 °C) also the best choice in the extraction of caffeine, trigonelline and nicotinic acid, especially when using Robusta coffee.
Conclusion
The two different espresso machines had showed quite different extraction kinetics of the EC, with Aurelia machine being more reliable in extracting EC with similar patterns of caffeine, trigonelline and nicotinic acid.
EC compositions varied according to the different espresso machine settings. Optimal parameters were set after quantitative and sensory panel assessments.
Acknowledgement
The research team (School of Pharmacy, University of Camerino), is grateful to Nuova Simonelli (Belforte del Chienti, Macerata, Italy) for providing coffee samples and EC machines and partial economic support.
References
[1] Maeztu, L., Sanz, C., Andueza, S., De Peña, M.P., Bello, J., Cid, C., 2001. J. Agric. Food Chem. 49, 5437–5444.
[2] Caprioli, G., Cortese, M., Cristalli, G., Maggi, F., Odello, L., Ricciutelli, M., Sagratini, G., Sirocchi, V., Tomassoni, G., Vittori, S., 2012. Food Chemistry 135, 1127–1133
Particle size distribution influences on Espresso Coffee extraction.
No full textEspresso coffee (EC) extraction depends with a great extent on coffee particle sizes produced by grinding, and also brewing process. To extract tempting aroma and taste in EC, the grinding process is a crucial step. The taste and flavor change in important manner owing to the particle size of ground coffee. This research aims at optimizing the impact of different particle size on aroma and bioactive compounds. In experimental part, quantitative and qualitative analyses were conducted on two cultivars: Arabica and Robusta [1]. The size of grinded coffee was between 200-400 and 400-1000 microns. EC extraction were in duplicate for each particle size samples with 12 and 14 grams of grinded coffee. The espresso machine settings are maintained at 9 bar and 92±20C. Volatile compounds were divided into family groups and identified by using HS-SPME-GC/MS [2]. Results confirmed a good extraction efficiency of caffeine, which accounted for 170 mg (200-400 microns) and 90 mg per cup (400-1000 microns), respectively.
References
[1] Caprioli G, Cortese M, Cristalli G, Maggi F, Odello L, Ricciutelli M, Sagratini G, Sirocchi V, Tomassoni G, Vittori S. Optimization of espresso machine parameters through the analysis of coffee odorants by HS-SPME-GC/MS. Food Chemistry. 2012;135(3):1127-1133.
[2] Sanchez Lopez JA, Wellinger M, Gloess AN, Zimmermann R, Yeretzian C. Extraction kinetics of coffee aroma compounds using a semi-automatic machine: On-line analysis by PTR-ToF-MS. International Journal of Mass Spectrometry. 2016;xxx:xxx-xxx.
[3] Folmer B, Blank I, Farah A, Giuliano P, Sandres D, Wille C. The Craft and Science of Coffee, London, UK: Elsevier, 2017
A new analytical method for the quantification of three Lignans in Coffee by HPLC-MS/MS Triple Quadrupole.
No full textLignans, compounds with two phenylpropanoid units, are present in high number of foodstuffs and beverages including coffee[1,2]. Our aim was to develop a new analytical method to quantify three lignans, i.e., secoisolariciresinol (SECO), lariciresinol (LARI) and matairesinol (MAT) in espresso (EC) and ground coffee by using HPLC-MS/MS Triple Quadrupole. Hence, different extraction methods including acid hydrolysis and enzymatic digestion have been evaluated. Subsequently, the most performing process was validated and applied to various coffee samples. Both SECO (from 27.9 to 52.0 μg l-1 in EC; from 84.4 to 257.8 μg Kg-1 in ground coffee) and LARI (from 5.3 to 27.8 μg l-1 in EC; from 26.1 to 86.2 μg Kg-1 in ground coffee) have been found in all coffee samples. Regular consumption of coffee can contribute to dietary lignan intakes.
References
1. “Plant and mammalian lignans: a review of source, intake, metabolism, intestinal bacteria and health”. J. M. Landete. (2012) Food Research International, 46, 410-424.
2. “Chromatographic analysis of lignans”. S. M. Willför, A. I. Smeds, B. R. Holmbom. (2006) Journal of Chromatography A, 1112, 64-77
Optimization of espresso coffee extraction through variation of particle sizes, perforated disk height and filter basket aimed at lowering the amount of ground coffee used
No full textEspresso machines maintain constant the extraction process of espresso coffee (EC), however, it is difficult to grind roasted coffee in homogeneous way. This research aims to investigate grinded beans at specific particle sizes in three variously designed filter baskets and to compare the concentration of bioactive compounds while decreasing the amount of ground coffee. Analyses on caffeine, trigonelline and chlorogenic acids are carried out with HPLC-VWD, while volatiles with HS-SPME/GC–MS. Extracting with smaller particles escalates the quantity of bioactive compounds. The amount of caffeine/cup increased moving from 500–1000 μm to 200–300 μm particle size, both in Arabica and Robusta for all filter baskets. Keeping constant the volume of EC at various heights of perforated disc, the amount of bioactive compounds at 12 g were only around 9% lower than at 14 g. The outcomes will support further studies on different extraction processes, to develop more sustainable and economically affordable coffee
The impact of different filter baskets, heights of perforated disc and amount of ground coffee on the extraction of organics acids and the main bioactive compounds in espresso coffee
No full textEspresso coffee (EC) is a complex and much appreciated beverage among coffee consumers. The extraction phase of EC, a combination of physical and chemical variables in a very short time, has a direct effect on the flavour of the beverage. This research aims to optimize the extraction process of EC by decreasing the amount of ground coffee from 14 g to 12 g (double cup), while keeping constant the particle size of ground coffee and the physical parameters of the espresso machine, making use of the following accessories: two different filter baskets, and four different heights of perforated discs (4–7 mm). Quantitative analyses on several organic acids (acetic, citric, caffeic, malic, tartaric) and caffeine, trigonelline, nicotinic and 5-caffeoylquinic acid are carried out with HPLC-VWD through a newly developed method. This combines the quantification of organic acids, obtained through HPLC-VWD, with the results of a sensory panel evaluation on the descriptive notes of EC. The outcomes will trigger and support further studies on different extraction processes, to develop more sustainable and economically affordable coffee of high quality
Development of a new extraction method for the quantification of lignans in espresso and roasted and ground coffee by HPLC-MS/MS triple quadrupole
No full textFrom biological point of view, lignans are interesting antioxidant compounds. They are part of phytoestrogens, natural molecules of plant origins, characterized by oestrogenic and anti-oestrogenic activities [1]. The analytical methods for lignan analysis change depending on different matrix and monitored compounds. Most used long purification, clean-up or derivatization steps [2]. Our goal was to develop an analytical method to quantify three lignans, i.e., secoisolariciresinol (SECO), lariciresinol (LARI) and matairesinol (MAT) in espresso (EC) and roasted and ground (R&G) coffee, avoiding long preparation and extraction processes. High performance liquid chromatography-mass spectrometry/mass spectrometry (HPLC-MS/MS) equipped with electrospray ionization (ESI) source was chosen as analytical instrument. Different hydrolytic and extraction processes, including acidic hydrolysis, enzymatic digestions and organic solvent extractions have been evaluated in liquid matrix (EC) and in solid matrix (R&G coffee). The most performing extraction process in EC and in R&G coffee were chosen, and once validated, applied to several 100% Coffea arabica ECs and different roasted and ground coffee samples. SECO (from 27.9 to 52.0 μg l-1 in EC; from 84.4 to 257.8 μg Kg-1 in ground coffee) and LARI (from 5.3 to 27.8 μg l-1 in EC; from 26.1 to 86.2 μg Kg-1 in ground coffee) were found in all coffee samples. Regular consumption of coffee can contribute to dietary lignan intakes.
References
[1] Landete JM. Plant and mammalian lignans: a review of source, intake, metabolism, intestinal bacteria and health. Food Res Int. 2012;46:410-424.
[2] Willför SM, Smeds A I, Holmbom BR. Chromatographic analysis of lignans. J Chromatogr. A. 2006;1112:64-77
The development of new extraction methods to quantify three lignans in espresso and roast and ground coffee.
No full textIntroduction:
Lignans, compounds with two phenylpropanoid units, possess various biological activities, i.e., antioxidant, estrogenic and anti-estrogenic [1]. Our aim was to develop an analytical method for the extraction and quantification of three lignans, namely secoisolariciresinol (SECO), matairesinol (MAT) and lariciresinol (LARI) in espresso (EC) and in roast and ground (R&G) coffee.
Methods:
Various extraction methods, i.e., acid and enzymatic hydrolysis and methanolic extractions, have been evaluated to extract target compounds from liquid (EC) and solid (R&G coffee) matrixes. As analytical instrument an HPLC-MS/MS triple quadrupole equipped with electrospray ionization (ESI) source was used operating in multiple reaction monitoring (MRM) mode.
Results:
The best lignan recovery values (from 93 to 98%) in EC were found using an enzymatic hydrolysis with clara-diastase at 10% (w/v), carrying out the digestion at 37°C for 3h. For lignan extraction from R&G coffee, the best performing method used again enzymatic digestion, but with taka-diastase 2% (w/v). Our analytical method showed good sensitivity, with limit of quantification (LOQ) ranging from 5 to 10 μg l-1, linearity (R2 ≥0.9944 for any target molecule) and repeatability, with RSDs ranging from 1.75 to 7.34% for intra-day repeatability and from 5.72 to 12.12% for inter-day repeatability. Once validated, the extraction methods have been applied to real EC and R&G coffee samples. We found a concentration of total lignans from 33.2 to 79.1 μg l-1 in EC samples and from 117.7 to 341.4 μg kg-1 in R&G coffee samples.
Conclusions:
A new analytical method for the extraction and quantification of lignans in EC and R&G coffee has been developed and validated [2]. Comparing the total amount of lignans in ECs with that in R&G coffee, the average of extraction yield was 95%. Lignans are completely extracted during the preparation of espresso coffee.
References
1. Ososki A. L., Kennelly E. J., Phytotherapy Research: An International Journal Devoted to Pharmacological and Toxicological Evaluation of Natural Product Derivatives, 17, 845-869 (2003).
2. Angeloni S., Navarini L., Sagratini G., Torregiani E., Vittori S., Caprioli G., Journal of Mass Spectrometry, 1–7 (2018). https://doi.org/10.1002/jms.4251
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