Emerging Green Techniques for the Extraction of Antioxidants from Agri-Food By-Products as Promising Ingredients for the Food Industry

Nowadays, the food industry is heavily involved in searching for green sources of valuable compounds, to be employed as potential food ingredients, to cater to the evolving consumers’ requirements for health-beneficial food ingredients. In this frame, agri-food by-products represent a low-cost source of natural bioactive compounds, including antioxidants. However, to effectively recover these intracellular compounds, it is necessary to reduce the mass transfer resistances represented by the cellular envelope, within which they are localized, to enhance their extractability. To this purpose, emerging extraction technologies, have been proposed, including Supercritical Fluid Extraction, Microwave-Assisted Extraction, Ultrasound-Assisted Extraction, High-Pressure Homogenization, Pulsed Electric Fields, High Voltage Electrical Discharges. These technologies demonstrated to be a sustainable alternative to conventional extraction, showing the potential to increase the extraction yield, decrease the extraction time and solvent consumption. Additionally, in green extraction processes, also the contribution of solvent selection, as well as environmental and economic aspects, represent a key factor. Therefore, this review focused on critically analyzing the main findings on the synergistic effect of low environmental impact technologies and green solvents towards the green extraction of antioxidants from food by-products, by discussing the main associated advantages and drawbacks, and the criteria of selection for process sustainability.

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Phenols and Antioxidant Activity in Vitro and in Vivo of Aqueous Extracts Obtained by Ultrasound-Assisted Extraction from Artichoke By-Products

Natural Product Communications ◽

10.1177/1934578x1400900924 ◽

2014 ◽

Vol 9 (9) ◽

pp. 1934578X1400900 ◽

Cited By ~ 5

Author(s):

Rossana Punzi ◽

Annalisa Paradiso ◽

Cristina Fasciano ◽

Antonio Trani ◽

Michele Faccia ◽

...

Keyword(s):

High Performance ◽

Food Industry ◽

Ultrasound Assisted Extraction ◽

Waste Products ◽

Antioxidant Power ◽

Assisted Extraction ◽

Ultrasound Assisted ◽

By Products

Artichoke by-products are rich in phenolic compounds although they represent a waste for the food industry. This paper examines the application of ultrasound-assisted extraction (UAE) for obtaining organic solvent-free extracts rich in nutraceuticals from artichoke scraps. Application of ultrasounds for 60 minutes on test samples, using water as a solvent, improved recovery of phenolic substances compared with untreated samples. Among the phenols detected by high performance liquid chromatography, 5- O-caffeoylquinic and 1,5-di- O-caffeoylquinic acids were identified. In vivo treatments of tobacco BY-2 cells with ultrasonic extracts consistently enhanced their antioxidant power, making the cells more resistant to heat stress. UAE applied to artichoke by-products, using water as a solvent, appears to be a powerful eco-friendly technique that can provide extracts rich in nutraceuticals and turn waste products into resources. The extracts could be advantageously utilized in the food industry to produce functional foods.

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Ultrasound-Assisted Extraction of Flavonoids from Kiwi Peel: Process Optimization and Bioactivity Assessment

Applied Sciences ◽

10.3390/app11146416 ◽

2021 ◽

Vol 11 (14) ◽

pp. 6416

Author(s):

Miguel Giordano ◽

José Pinela ◽

Maria Inês Dias ◽

Ricardo C. Calhelha ◽

Dejan Stojković ◽

...

Keyword(s):

Phenolic Compounds ◽

Low Cost ◽

Vero Cells ◽

Extraction Yield ◽

Raw Material ◽

Ultrasonic Power ◽

Ultrasound Assisted Extraction ◽

Food Preservatives ◽

Assisted Extraction ◽

Ultrasound Assisted

The nutritional quality of kiwifruit has been highlighted by several studies, while its peel is typically discarded as a by-product with no commercial value. This study was carried out to optimize the ultrasound-assisted extraction (UAE) of phenolic compounds from kiwi peel. Three independent variables (time (t), ultrasonic power (P) and ethanol concentration (EtOH)) were combined in a five-level central composite rotatable design coupled with the response surface methodology (RSM). The extraction yield determined gravimetrically and the content of phenolic compounds identified by HPLC-DAD-ESI/MSn (namely two quercetin glycosides, one catechin isomer and one B-type (epi)catechin dimer) were the experimental responses used in the optimization. The polynomial models were successfully fitted to the experimental data and used to determine the optimal UAE conditions. The sonication of the sample at 94.4 W for 14.8 min, using 68.4% ethanol, resulted in a maximum of 1.51 ± 0.04 mg of flavonoids per g of extract, a result that allowed the experimental validation of the predictive model. The kiwi peel extract obtained under optimized conditions showed somehow promising bioactive properties, including antioxidant and antimicrobial effects, and no toxicity to Vero cells. Overall, this study contributes to the valorization of kiwi peel as a low-cost raw material for the development of natural ingredients (such as food preservatives) and also to the resource-use efficiency and circular bioeconomy.

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Ultrasound as a Rapid and Low-Cost Extraction Procedure to Obtain Anthocyanin-Based Colorants from Prunus spinosa L. Fruit Epicarp: Comparative Study with Conventional Heat-Based Extraction

Molecules ◽

10.3390/molecules24030573 ◽

2019 ◽

Vol 24 (3) ◽

pp. 573 ◽

Cited By ~ 5

Author(s):

Maria G. Leichtweis ◽

Carla Pereira ◽

M.A. Prieto ◽

Maria Filomena Barreiro ◽

Lillian Barros ◽

...

Keyword(s):

Low Cost ◽

Extraction Procedure ◽

Pilot Scale ◽

Extraction Yield ◽

Heat Extraction ◽

Anthocyanin Content ◽

Extraction Temperature ◽

Ultrasound Assisted Extraction ◽

Prunus Spinosa ◽

Assisted Extraction

An ultrasound rapid and low-cost procedure for anthocyanin-based colorants from Prunus spinosa L. fruit epicarp was developed, and the advantages were compared with conventional heat-based extraction. To obtain the conditions that maximize anthocyanins’ extraction, a response surface methodology was applied using the variables of time, temperature, and ethanol content, in the case of heat extraction, whereas for ultrasound assisted extraction, temperature was replaced by ultrasound power. Two anthocyanin compounds were identified by HPLC-DAD-ESI/MS—namely, cyanidin 3-rutinoside and peonidin 3-rutinoside. The responses used were the extraction yield and the content of the identified anthocyanins. Ultrasound extraction was the most effective method at 5.00 ± 0.15 min, 400.00 ± 32.00 W, and 47.98% ± 2.88% of ethanol obtaining 68.60% ± 2.06% of extracted residue, with an anthocyanin content of 18.17 mg/g (extract-basis) and 11.76 mg/g (epicarp-basis). Overall, a viable green process was achieved that could be used to support pilot-scale studies for industrial production of anthocyanin-based colorants from P. spinosa fruit epicarp.

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New Approach to Enrich Pasta with Polyphenols from Grape Marc

Journal of Chemistry ◽

10.1155/2015/734578 ◽

2015 ◽

Vol 2015 ◽

pp. 1-8 ◽

Cited By ~ 16

Author(s):

V. Marinelli ◽

L. Padalino ◽

D. Nardiello ◽

M. A. Del Nobile ◽

A. Conte

Keyword(s):

Antioxidant Activity ◽

Food Industry ◽

Cooking Quality ◽

Total Phenolic ◽

Ultrasound Assisted Extraction ◽

New Approach ◽

Grape Marc ◽

Assisted Extraction ◽

Water As Solvent ◽

By Products

Food industry produces significant amount of waste that represents a problem for the sector. However, by-products are also promising sources of compounds which may be reused for their nutritional properties. The aim of this work is to exploit wine-making by-products, obtaining an extract by ultrasound-assisted extraction only using water as solvent. The characteristics of spaghetti enriched with grape marc were assessed and compared to control samples. In particular, total phenolic and flavonoids contents, the antioxidant activity, the cooking quality, and the sensory acceptability were evaluated at various steps of pasta production. The enriched spaghetti showed higher total phenolic and flavonoids contents and higher antioxidant activity than the control pasta. In addition, low cooking losses were found. In terms of sensory properties fortified pasta is acceptable as the traditional product, thus demonstrating that it is possible to exploit food waste to better satisfy consumer demand for healthy food products in a more sustainable perspective.

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Green Extraction Methods for Extraction of Polyphenolic Compounds from Blueberry Pomace

Foods ◽

10.3390/foods9111521 ◽

2020 ◽

Vol 9 (11) ◽

pp. 1521

Author(s):

Ante Lončarić ◽

Maria Celeiro ◽

Antun Jozinović ◽

Josip Jelinić ◽

Tihomir Kovač ◽

...

Keyword(s):

Liquid Chromatography ◽

Energy Input ◽

Extraction Methods ◽

Extraction Yield ◽

Polyphenolic Compounds ◽

Array Detector ◽

Ultrasound Assisted Extraction ◽

Green Extraction ◽

Assisted Extraction ◽

Tandem Mass Spectrometric

In this study, green extraction methods—high voltage electrical discharges (HVED), pulsed electric field (PEF), and ultrasound-assisted extraction (UAE)—were compared in terms of extraction yield of total and individual polyphenolic compounds, as well as the antioxidant capacity of blueberry pomace extracts. All extractions were performed with methanol- and ethanol-based solvents. The highest total polyphenols content (TPC) (10.52 mg of gallic acid equivalent (GAE) per g of dry weight (dw)) and antioxidant activity (AA) (0.83 mmol TE/g dw) were obtained by PEF-assisted extraction in the ethanol-based solvent after 100 pulses and 20 kV/cm, which corresponds to an energy input of 41.03 kJ/kg. A total of eighteen individual polyphenols were identified in all investigated blueberry pomace extracts by high-performance liquid chromatography with the diode-array detector (HPLC-DAD) and liquid chromatography electrospray ionization tandem mass spectrometric (LC-(HESI)-MS/MS). The highest anthocyanin (1757.32 µg/g of dw) and flavanol (297.86 µg/g of dw) yields were obtained in the methanol-based solvent, while the highest phenolic acid (625.47 µg/g of dw) and flavonol (157.54 µg/g of dw) yields were obtained in the ethanol-based solvent by PEF-assisted extraction at the energy input of 41.03 kJ/kg. These results indicated that PEF is a promising green extraction method which can improve the blueberry pomace’s polyphenol extraction yield.

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Application of Tea Extract in Food Industry

Current Nutrition & Food Science ◽

10.2174/1573401316666191218120443 ◽

2020 ◽

Vol 16 (7) ◽

pp. 998-1004

Author(s):

Aziz H. Rad ◽

Raana B. Fathipour ◽

Fariba K. Bidgoli ◽

Aslan Azizi

Keyword(s):

Food Industry ◽

Health Benefits ◽

Epigallocatechin Gallate ◽

Water Extraction ◽

Ultrasound Assisted Extraction ◽

Epicatechin Gallate ◽

Microwave Assisted ◽

Assisted Extraction ◽

Main Components ◽

Tea Extract

Background and Objectives: Tea is considered one of the most consumed drinks around the world and the health benefits of it have recently attracted the attention of different researchers. It has also been proven beneficial in preventing the danger of some diseases like cancer and cardiovascular problems. Further, lipid oxidation is one of the major problems in food products. Considering the above-mentioned issues, the present review focused on various techniques used to extract polyphenols from different kinds of tea, as well as their use in the food industry. Results and Conclusion: Based on our findings in this review, the main components of tea are polyphenols that have health benefits and include catechins, epicatechin, epigallocatechin, epicatechin gallate, epigallocatechin gallate, gallic acid, flavonoids, flavonols, and theophlavins. From these components, catechin is regarded as the most beneficial component. Many techniques have been discovered and reformed to extract tea compounds such as solvent-based extraction, microwave-assisted water extraction, and ultrasound-assisted extraction techniques. Overall, the microwave-assisted water extraction method is a useful method for extracting tea polyphenols, which may be used in the meat, oil, and dairy industries.

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Extraction of Phenolic Compounds and Terpenes from Cannabis sativa L. By-Products: From Conventional to Intensified Processes

Antioxidants ◽

10.3390/antiox10060942 ◽

2021 ◽

Vol 10 (6) ◽

pp. 942

Author(s):

Emilie Isidore ◽

Hamza Karim ◽

Irina Ioannou

Keyword(s):

Phenolic Compounds ◽

Cannabis Sativa ◽

Biological Activities ◽

Operating Conditions ◽

Extraction Techniques ◽

Ultrasound Assisted Extraction ◽

Assisted Extraction ◽

Whole Plant ◽

Conventional Solvent Extraction ◽

By Products

Cannabis sativa L. is a controversial crop due to its high tetrahydrocannabinol content varieties; however, the hemp varieties get an increased interest. This paper describes (i) the main categories of phenolic compounds (flavonoids, stilbenoids and lignans) and terpenes (monoterpenes and sesquiterpenes) from C. sativa by-products and their biological activities and (ii) the main extraction techniques for their recovery. It includes not only common techniques such as conventional solvent extraction, and hydrodistillation, but also intensification and emerging techniques such as ultrasound-assisted extraction or supercritical CO2 extraction. The effect of the operating conditions on the yield and composition of these categories of phenolic compounds and terpenes was discussed. A thorough investigation of innovative extraction techniques is indeed crucial for the extraction of phenolic compounds and terpenes from cannabis toward a sustainable industrial valorization of the whole plant.

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Monomers, Materials and Energy from Coffee By-Products: A Review

Sustainability ◽

10.3390/su13126921 ◽

2021 ◽

Vol 13 (12) ◽

pp. 6921

Author(s):

Laura Sisti ◽

Annamaria Celli ◽

Grazia Totaro ◽

Patrizia Cinelli ◽

Francesca Signori ◽

...

Keyword(s):

Circular Economy ◽

Food Industry ◽

Food Packaging ◽

Low Cost ◽

Biofuel Production ◽

Material Technology ◽

Coffee Production ◽

Coffee Pulp ◽

Coffee Waste ◽

By Products

In recent years, the circular economy and sustainability have gained attention in the food industry aimed at recycling food industrial waste and residues. For example, several plant-based materials are nowadays used in packaging and biofuel production. Among them, by-products and waste from coffee processing constitute a largely available, low cost, good quality resource. Coffee production includes many steps, in which by-products are generated including coffee pulp, coffee husks, silver skin and spent coffee. This review aims to analyze the reasons why coffee waste can be considered as a valuable source in recycling strategies for the sustainable production of bio-based chemicals, materials and fuels. It addresses the most recent advances in monomer, polymer and plastic filler productions and applications based on the development of viable biorefinery technologies. The exploration of strategies to unlock the potential of this biomass for fuel productions is also revised. Coffee by-products valorization is a clear example of waste biorefinery. Future applications in areas such as biomedicine, food packaging and material technology should be taken into consideration. However, further efforts in techno-economic analysis and the assessment of the feasibility of valorization processes on an industrial scale are needed.

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Technologies and Extraction Methods of Polyphenolic Compounds Derived from Pomegranate (Punica granatum) Peels. A Mini Review

Processes ◽

10.3390/pr9020236 ◽

2021 ◽

Vol 9 (2) ◽

pp. 236

Author(s):

Dimitrios Lampakis ◽

Prodromos Skenderidis ◽

Stefanos Leontopoulos

Keyword(s):

Electric Fields ◽

Bioactive Compounds ◽

New Technologies ◽

Ohmic Heating ◽

Punica Granatum ◽

Extraction Methods ◽

Added Value ◽

Green Solvents ◽

Ultrasound Assisted Extraction ◽

Functional Product

The interest in using plant by-product extracts as functional ingredients is continuously rising due to environmental and financial prospects. The development of new technologies has led to the achievement of aqueous extracts with high bioactivity that is preferable due to organic solvents nonuse. Recently, widely applied and emerging technologies, such as Simple Stirring, Pressure-Applied Extraction, Enzymatic Extraction, Ultrasound-Assisted Extraction, Pulsed Electric Fields, High Hydrostatic Pressure, Ohmic Heating, Microwave Assistant Extraction and the use of “green” solvents such as the deep eutectic solvents, have been investigated in order to contribute to the minimization of disadvantages on the extraction of bioactive compounds. This review is focused on bioactive compounds derived from pomegranate (Punica granatum) peels and highlighted the most attractive extraction methods. It is believed that these findings could be a useful tool for the pomegranate juices industry to apply an effective and economically viable extraction process, transforming a by-product to a high added value functional product.

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Mathematical Modelling of Ultrasound-Assisted Extraction Kinetics of Bioactive Compounds from Artichoke By-Products

Foods ◽

10.3390/foods10050931 ◽

2021 ◽

Vol 10 (5) ◽

pp. 931

Author(s):

Cristina Reche ◽

Carmen Rosselló ◽

Mónica M. Umaña ◽

Valeria Eim ◽

Susana Simal

Keyword(s):

Power Density ◽

Bioactive Compounds ◽

Extraction Yield ◽

Total Phenolic ◽

Model Parameters ◽

Ultrasound Assisted Extraction ◽

Yield Curves ◽

Assisted Extraction ◽

Ultrasound Assisted ◽

Ultrasound Power

Valorization of an artichoke by-product, rich in bioactive compounds, by ultrasound-assisted extraction, is proposed. The extraction yield curves of total phenolic content (TPC) and chlorogenic acid content (CAC) in 20% ethanol (v/v) with agitation (100 rpm) and ultrasound (200 and 335 W/L) were determined at 25, 40, and 60 °C. A mathematical model considering simultaneous diffusion and convection is proposed to simulate the extraction curves and to quantify both temperature and ultrasound power density effects in terms of the model parameters variation. The effective diffusion coefficient exhibited temperature dependence (72% increase for TPC from 25 °C to 60 °C), whereas the external mass transfer coefficient and the equilibrium extraction yield depended on both temperature (72% and 90% increases for TPC from 25 to 60 °C) and ultrasound power density (26 and 51% increases for TPC from 0 (agitation) to 335 W/L). The model allowed the accurate curves simulation, the average mean relative error being 5.3 ± 2.6%. Thus, the need of considering two resistances in series to satisfactorily simulate the extraction yield curves could be related to the diffusion of the bioactive compound from inside the vegetable cells toward the intercellular volume and from there, to the liquid phase.

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