Roasted Coffee Oil Research Articles

Lipidomics reveals the effects of various processing parameters on the lipid composition and activity of roasted coffee oil

Lipids are an important part of the roasting and extraction of coffee, as they impart flavor and aroma to the coffee while it is roasting. Here, coffee oil was extracted from roasted coffee beans, and several ethanol extraction (EE), ultrasound extraction (UE), microwave extraction (ME), and ultrasonic-enzyme extraction (UME) treatments were performed. The oils from the UME group were better in terms of color, acid value, peroxide value, tocopherol content, and other indicators. Glycerolipids, glycerophospholipids, and sphingolipids were evaluated in the three groups via coffee oil analysis via quantitative lipidomics. The sphingolipid and glycerophospholipid metabolic pathways showed considerable lipid enrichment when the identified differential lipids were subjected to metabolic pathway enrichment. Coffee oils subjected to various processing techniques showed substantial changes, as determined by multivariate regression; significantly different lipids were identified as candidate biomarkers. The production of coffee goods can benefit from these new insights into the extraction and application of coffee oil.

Coffee Oil Extraction Methods: A Review.

Green and roasted coffee oils are products rich in bioactive compounds, such as linoleic acid and the diterpenes cafestol and kahweol, being a potential ingredient for food and cosmetic industries. An overview of oil extraction techniques most applied for coffee beans and their influence on the oil composition is presented. Both green and roasted coffee oil extractions are highlighted. Pressing, Soxhlet, microwave, and supercritical fluid extraction were the most used techniques used for coffee oil extraction. Conventional Soxhlet is most used on a lab scale, while pressing is most used in industry. Supercritical fluid extraction has also been evaluated mainly due to the environmental approach. One of the highlighted activities in Brazilian agribusiness is the industrialization of oils due to their increasing use in the formulation of cosmetics, pharmaceuticals, and foods. Green coffee oil (raw bean) has desirable bioactive compounds, increasing the interest of private companies and research institutions in its extraction process to preserve the properties contained in the oils.

Storage Stability of Spray- and Freeze-Dried Chitosan-Based Pickering Emulsions Containing Roasted Coffee Oil: Color Evaluation, Lipid Oxidation, and Volatile Compounds

Drying Pickering o/w emulsions has been considered as a promising strategy to produce oil microcapsules, as long as their quality parameters can be preserved over storage. In this sense, it is shown as an interesting alternative to preserve the quality of roasted coffee oil, a valuable agroindustrial byproduct. Thus, freeze- and spray-dried chitosan-based Pickering emulsions of roasted coffee oil were evaluated over 30 days of storage at 25 °C together with the non-encapsulated oil as a control. Water sorption isotherms were determined, whereas color, oxidative stability (peroxide value and conjugated dienes) and volatile compounds were assessed over the storage period. Type II isotherms and Guggenheim–Anderson–Boer (GAB) model parameters showed that water binding was impaired by the surface oil in freeze-dried samples. Oxidation was maintained under acceptable values over the storage for all samples, with slightly higher protection also observed for volatile compounds in the spray-dried particles. The powdered emulsions were able to suitably preserve the oil’s quality over 30 days of storage, enabling its commercialization and application as a food ingredient and potential flavoring.

Characterization and Sensory Evaluation of a Cosmeceutical Formulation for the Eye Area with Roasted Coffee Oil Microcapsules

The objective of this work was to characterize a cosmeceutical formulation for the eye area with roasted coffee oil microcapsules (MOF) and evaluate the acceptance and effects of its use by consumers. MOF had 3% microcapsules produced by complex coacervation; a basic formulation (BF) was used for comparison. The addition of microcapsules did not affect the pH (4.52), density (0.99 g mL−1), consistency (0.77 N s), and viscosity index (0.25 N s) of the formulation. However, a reduction in spreadability, firmness, and cohesiveness was observed. The 58 assessors received one kit with the formulations and a notebook with instructions to carry out the tests at home. They were instructed to apply the cream for 28 days and evaluate the attributes of application and treatment effects on 7-point category scales. The effect of oil addition observed in the physical tests was not sensorially perceived for spreadability and tackiness (6.0 and 5.6, respectively), indicating approval and easiness of application. The perception of the benefits (increase in smoothness, hydration, firmness, elasticity, and skin general appearance, and reduction in signs of fatigue and wrinkles/fine lines) was similar comparing MOF and BF. In conclusion, the coffee oil microcapsule is a viable ingredient for dermocosmetics with sensory acceptance.

Eye Cosmeceutical Formulations with Roasted Coffee Oil in Free and Microencapsulated Forms: Development and Preliminary Stability Study

AbstractThis research aims to develop eye cosmeceutical formulations with roasted coffee oil. Oil is used in form and microencapsulated forms. A preliminary stability study is performed, and base formulation (BF) is used for comparison. All formulations are stable and firm. Formulations with oil in free (OF) or microencapsulated (MOF) form show color and aroma of coffee. Initially, MOF is the most acid, and BF shows the highest peroxide value (PV) and the lowest sun protection factor (SPF) values and no antioxidant activity (AA). OF and MOF show AA and high SPF ; these parameters are little affected by storage, and an increase in PV is observed only for BF. Cosmeceutical formulations with roasted coffee oil present stability and good potential for dermocosmetic products.Practical Applications: Coffee oil is known for its AA and protection against sunlight UV radiation, so it fits the interest of cosmetics and personal care producers for bioactive ingredients from natural sources. The cosmetics industry uses green coffee oil; however, roasted coffee oil is of more interest since it is a coproduct of the soluble coffee industry. The authors are unaware of studies proposing the use of microcapsules (produced by complex coacervation) of roasted coffee oil in cosmeceutical formulations.

Microencapsulation of roasted coffee oil Pickering emulsions using spray‐ and freeze‐drying: physical, structural and in vitro bioaccessibility studies

SummaryMicrocapsules produced from well‐defined emulsion templates are an interesting alternative for lipid encapsulation. This work aimed to produce microcapsules by the freeze‐drying (FD) and spray‐drying (SD) of Pickering emulsions of roasted coffee oil (RCO) stabilised with chitosan nanoparticles produced by self‐aggregation or by crosslinking with tripolyphosphate. The dried microcapsules were characterised in terms of particle size, oil retention and structure; furthermore, the in vitro bioaccessibility of polyphenols from microencapsulated RCO was investigated. The use of chitosan nanoparticles to stabilise the emulsions increased oil retention in the microcapsules giving values between 83.04% and 95.36%. SD produced spherical microcapsules with small particle sizes (˜11 μm), whereas FD microcapsules showed an irregular shape and porous structure. Although FD had the lowest impact on the bioactive compounds, SD promoted better protection for phenolic compounds and antioxidant activity during in vitro digestion.

Adulticidal Activity of Coffee Essential Oils against Two Fruit Fly Species (Tephritidae) under Laboratory Conditions

The aim of this study was to evaluate the adulticidal effects of green coffee oil (GCO) and roasted coffee oil (RCO) on two species of fruit flies (Tephritidae) include Ceratitis capitata (Wiedemann) and Anastrepha fraterculus (Wiedemann). Adult flies of both species were exposed to GCO and RCO at 2%, 3%, and 4% dilutions in water under Potter spray tower. In general, exposure to GCO and RCO at the three dilutions resulted in higher numbers of dead adults of both species compared to the control populations. The mortalities increased substantially between 60–90 minutes after initial exposure. The 2% GCO dilution reached a maximum of 77.0% corrected mortality of A. fraterculus at 360 minutes. In general, the toxic effect of coffee oils occurred more rapidly in C. capitata than in A. fraterculus. GCO (2% and 3%) and RCO (2%) showed promising results for fruit fly management.

Ultrasound-Assisted Emulsification of Roasted Coffee Oil in Complex Coacervates and Real-time Coffee Aroma Release by PTR-ToF–MS

Ultrasound-Assisted Emulsification of Roasted Coffee Oil in Complex Coacervates and Real-time Coffee Aroma Release by PTR-ToF–MS

Roasted coffee oil microencapsulation by spray drying and complex coacervation techniques: Characteristics of the particles and sensory effect

The objective of this research was to microencapsulate roasted coffee oil using spray drying (SD) and complex coacervation (CC) techniques and to compare the microparticles properties and their sensory impact on the perception of soluble coffee brew aroma. Starch was used as wall material for spray dried microparticles (MSD), and gelatin and gum Arabic for that produced by complex coacervation (MCC). Ultrasound stable emulsions were obtained. Both microparticles presented a continuous wall and similar glass transition temperature (49.3 °C). MSD had 10.2% oil content and low surface oil content, and high solubility and wettability. MCC stood out for its high oil content (42.8%) and larger diameter (125 μm). Sensory evaluation showed that, when dissolved in hot water, microparticles provided a coffee aroma. Despite the MCC brew was preferred by assessors, the perception of coffee aroma intensity during the preparation of a soluble coffee brew containing MSD or MCC were similar.

Whey Protein Isolate Microgel Properties Tuned by Crosslinking with Organic Acids to Achieve Stabilization of Pickering Emulsions.

Whey protein isolate (WPI) can be used effectively to produce food-grade particles for stabilizing Pickering emulsions. In the present study, crosslinking of WPI microgels using organic acids (tannic and citric acids) is proposed to improve their functionality in emulsions containing roasted coffee oil. It was demonstrated that crosslinking of WPI by organic acids reduces the microgels’ size from ≈1850 nm to 185 nm and increases their contact angle compared to conventional WPI microgels, achieving values as high as 60°. This led to the higher physical stability of Pickering emulsions: the higher contact angle and smaller particle size of acid-crosslinked microgels contribute to the formation of a thinner layer of particles on the oil/water (O/W) interface that is located mostly in the water phase, thus forming an effective barrier against droplet coalescence. Particularly, emulsions stabilized by tannic acid-crosslinked WPI microgels presented neither creaming nor sedimentation up to 7 days of storage. The present work demonstrates that the functionality of these crosslinked WPI microgels can be tweaked considerably, which is an asset compared to other food-grade particles that mostly need to be used as such to comply with the clean-label policy. In addition, the applications of these particles for an emulsion are much more diverse as of the starting material.

Quality attributes of roasted Arabica coffee oil extracted by pressing: composition, antioxidant activity, sun protection factor and other physical and chemical parameters

This research reports a comprehensive characterization of the composition profile and physical and chemical characteristics of roasted Arabica coffee oil obtained by mechanical pressing. The oil presented a peroxide value of 3.21 meq·kg-1 and an acid value of 7.3 mg KOH·g-1. A higher proportion of unsaturated fatty acids (58%), predominantly linoleic (L) and palmitic (P) acids, was observed; PLL and PLP were estimated as the main triacylglycerols. The oil was characterized by high contents in diterpenes and tocopherols (3720 and 913 mg·100g-1, respectively), the presence of caffeine and chlorogenic acids, as well as a high sun protection factor (9.7) and ABTS free radical-scavenging capacity (12.5 mg Trolox·mL-1). Among the 35 volatile compounds studied, furfurythiol and pyrazines were the main components of the oil. These properties showed that roasted coffee oil has good potential for use in food and cosmetics.

The role of ultrasound-assisted emulsification of roasted coffee oil on aroma profile in spray-dried microparticles and its dynamic release by PTR-ToF–MS

This work evaluated the use of roasted coffee oil (RCO) and the effects of ultrasound (US)-assisted emulsification on RCO-in-water emulsion properties, the changes in the composition of volatile organic compounds (VOCs) of roasted coffee aroma during US and microencapsulation by spray drying, and VOCs release profile upon instant coffee reconstitution. VOCs were determined by gas chromatography-mass spectrometry, and the release profile was monitored in real-time by Proton Transfer Reaction Time-of-Flight Mass Spectrometry (PTR-ToF–MS). US was found to be effective in producing stable submicron emulsions (≤ 2.0 µm) that resulted in high encapsulation efficiency (> 90%) of the microparticles. Significant changes were detected in VOC composition throughout the microencapsulation process. The addition of microparticles loaded with RCO in instant coffee did not change the VOCs release profile during the brew preparation but was effective in increasing coffee aroma.

Modulation of aroma release of instant coffees through microparticles of roasted coffee oil

We report, on the successful addition of spray-dried microparticles containing roasted coffee oil, to soluble coffee (SC) and instant cappuccino (IC), to increase and tailor aroma release. Using PTR-ToF-MS (Proton Transfer Reaction Time-of-Flight Mass Spectrometry), five parameters were defined from time series intensity for each VOC, to compare the performance of different products: total area under the curve (AUC), area under the curve of burst (AUC-burst), maximum signal intensity, final intensity (5 min), and ratio AUC-burst/AUC. Microparticles with higher loads of roasted coffee oil were effective in increasing aroma intensity in SC while, for IC, all loads of microparticles improved aroma intensity. Volatility drove the VOC release in SC, and volatility and polarity for IC. Most compounds reached maximum headspace concentration in < 16 s upon start of reconstitution. These results open new perspectives for the development of instant coffee products and demonstrate their unique aroma release characteristics.

Самопроизвольное осаждение кофеина из сверхкритических экстрактов обжаренных зерен кофе

An unexpected effect of spontaneous caffeine precipitation from roasted coffee extracts obtained by supercritical fluid extraction was discovered. The effect is observed for various sorts of coffee when extraction pressure is roughly above 40 MPa. Simple centrifugation of such extracts allows obtaining two valuable products,decaffeinated roasted coffee oil and caffeine, which can be used as functional ingredients in food and cosmetics.

Digestibility and Bioaccessibility of Pickering Emulsions of Roasted Coffee Oil Stabilized by Chitosan and Chitosan-Sodium Tripolyphosphate Nanoparticles

Due to the valuable lipid fraction composition present in roasted coffee oil, it has become important to develop methods that modify its structure, such as emulsion-based encapsulation systems, favoring its use in food industry. Pickering emulsions have appeared as a potential alternative to protect oil droplets stabilized by solid particles rather than the use of surfactants. This work investigated the ability of chitosan (CS) nanoparticles produced by deprotonation and by ionic gelation to stabilize emulsions with different lipid phase content as an alternative to encapsulate roasted coffee oil. An in vitro digestion model consisting of mouth, gastric and intestinal phases was used to characterize the rate and extent of lipid phase digestion, emulsion microstructure, and bioaccessibility of total phenolic compounds. All emulsions presented some structural changes attributed to flocculation and coalescence throughout simulated gastrointestinal digestion. Better droplet stabilization using the deprotonation method was achieved when lower oil content was used, leading to higher bioaccessibility of total phenolic compounds.

Nanoencapsulation of roasted coffee bean oil in whey protein wall system through nanospray drying

Roasted coffee bean oil is an important by-product obtained from the coffee industry. In this study, roasted coffee bean oil was nanoencapsulated in whey protein wall system, using nanospray drying (NSD). The structural properties and thermal behavior of the resultant encapsulate were studied in comparison with that obtained through conventional spray drying. From the dynamic light scattering-based particle size measurement, the mean particle diameter of the nanospray-dried encapsulates was found to be 304.9 ± 99.4 nm. Further, image analysis showed that the nanoencapsulates were about 11-fold smaller than the microencapsulates. NSD resulted in a more uniform particle size distribution of the coffee oil nanoencapsulates than its microencapsulated counterpart. Study of morphology by scanning electron microscopy revealed nanosized, smooth, and spherical particles of the nanospray-dried encapsulate. Whereas, microencapsulates showed both smooth-spherical and cap-shaped, dented particles. Thermal stability analysis by differential scanning calorimetry indicated the protective effect of encapsulation on coffee oil constituents. Practical applications The results of this study established the nanospray-drying process as a potential technique for the nanoencapsulation for roasted coffee oil. The inferences from this research work would be useful to the food, ingredient, and flavoring industries.

Topical use and systemic action of green and roasted coffee oils and ground oils in a cutaneous incision model in rats (Rattus norvegicus albinus).

IntroductionWounds are a common health problem. Coffee is widely consumed and its oil contains essential fatty acids. We evaluated the local (skin) and systemic effects associated with the topical use of coffee oils in rats.MethodsPunch skin wounds (6 mm) incisions were generated on the backs of 75 rats. Saline (SS), mineral oil (MO), green coffee oil (GCO), roasted coffee oil (RCO), green coffee ground oil (GCGO) or roasted coffee ground oil (RCGO) were topically applied to the wounds. Healing was evaluated by visual and histological/morphometric optical microscopy examination; second harmonics generation (SHG) microscopy, wound tissue q-PCR (values in fold-change) and blood serum (ELISA, values in pg/mL).ResultsRCO treated animals presented faster wound healing (0.986 vs. 0.422), higher mRNA expression of IGF-1 (2.78 vs. 1.00, p = 0.01), IL-6 (10.72 vs. 1.00, p = 0.001) and IL-23 (4.10 vs. 1.2, p = 0.05) in early stages of wound healing; higher IL-12 (3.32 vs. 1.00, p = 0.05) in the later stages; and lower serum levels of IFN-γ (11.97 vs. 196.45, p = 0.01). GCO treatment led to higher mRNA expression of IL-6 (day 2: 7.94 vs. 1.00, p = 0.001 and day 4: 6.90 vs. 1.00, p = 0.01) and IL-23 (7.93 vs. 1.20, p = 0.001) in the early stages. The RCO treatment also produced higher serum IFN-α levels throughout the experiment (day 2: 52.53 vs. 21.20; day 4: 46.98 vs.21.56; day 10: 83.61 vs. 25.69, p = 0.05) and lower levels of IL-4 (day 4: 0.9 vs.13.36, p = 0.01), adiponectin (day 10: 8,367.47 vs. 16,526.38, p = 0.001) and IFN-γ (day 4: 43.03 vs.196.45, p = 0.05). The SHG analysis showed a higher collagen density in the RCO and GCO treatments (p = 0.05).ConclusionTopical treatment with coffee oils led to systemic actions and faster wound healing in rats. Further studies should be performed are necessary to assess the safety of topical vegetal oil use for skin lesions.

Crude ethanolic extract from spent coffee grounds: Volatile and functional properties

Espresso capsule consumption and spent coffee ground (SCG) generation have increased, and the present study was undertaken to evaluate the volatile profile (VP), the antioxidant activity (AA) and the sun protection factor (SPF) of the Crude ethanolic extract obtained from the SCG in capsules. The extract yield was superior to the ether yield because a higher unsaponifiable matter (U.M.) amount was recovered by ethanol. The obtained VP (70 compounds) was typical of roasted coffee oil. Furthermore, chemometric analysis using principal components (PCA) discriminated the extracts and grouped the replicates for each sample, which showed the repeatability of the extraction process. The AA ranged from 18.4 to 23.6 (mg extract mg DPPH−1) and the SPF from 2.27 to 2.76. The combination of the coffee VP, AA and SPF gave the espresso SCG’s crude ethanolicextract, desirable properties that can be used in cosmetic and food industries.

Microencapsulation of Roasted Coffee Oil by Complex Coacervation with Gelatin/Gum Arabic Enzymatically Crosslinked

The roasted coffee oil is a coffee industry byproduct composed by a great number of compounds including the volatiles, responsible by coffee aroma. The main objetive of the present work is the encapsulation of roasted coffee oil in enzimatically crosslinked gelatin and gum Arabic microcapsules. The microcapsules were obtained by complex coacervation. The effect of the roasted coffee oil amount used and the stirring rate on the average diameter, oil recovery and encapsulation efficiency were evaluated. The microcapsules presented average diameter up to 29.30 ± 1.28 µm with narrow size distributions. The results varied from 78.45 ± 2.47 to 100.70 ± 5.23 % (oil recovery) and 32.50 ± 3.53 to 71.00 ± 4.24 % (encapsulation efficiency). The water sorption isotherm of microcapsules was evaluated at 25 oC and the results were fitted with the Guggenhein-Anderson-de Boer (GAB) model, presenting a R 2 equal to 0.9892 and “J” shape behavior. Finally, the crosslinking reaction was investigated by Fourier Transform Infrared Spectroscopy (FTIR), showing that the crosslinking reaction promoted by transglutaminase introduced a band in microcapsules spectra located at 1550 cm -1 corresponding to the monosubstituted amide.

Isolation and characterization of major diterpenes from C. canephora roasted coffee oil

A simple laboratory procedure for the isolation of pure cafestol and 16-O-methylcafestol together with β-sitosterol from coffee is disclosed. Cafestol and 16-O-methylcafestol have been exhaustively characterized through 1D and 2D 1H, 13C NMR, CD and X-ray diffraction. For the first time, the molecular structure of cafestol is reported and the assignment of the absolute configuration is unequivocally given by exploiting anomalous scattering of a brominated derivative.