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Kim S, Kim JC, Kim YY, Yang JE, Lee HM, Hwang IM, Park HW, Kim HM. Utilization of coffee waste as a sustainable feedstock for high-yield lactic acid production through microbial fermentation. THE SCIENCE OF THE TOTAL ENVIRONMENT 2024; 912:169521. [PMID: 38141985 DOI: 10.1016/j.scitotenv.2023.169521] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/06/2023] [Revised: 11/27/2023] [Accepted: 12/17/2023] [Indexed: 12/25/2023]
Abstract
Lactic acid is an important industrial precursor; however, high substrate costs are a major challenge in microbial fermentation-based lactic acid production. Coffee waste is a sustainable feedstock alternative for lactic acid production via microbial fermentation. Herein, the feasibility of coffee waste as a feedstock was explored by employing appropriate pretreatment methods and optimizing enzyme combinations. Coffee waste pretreatment with hydrogen peroxide and acetic acid along with a combination of Viscozyme L, Celluclast 1.5 L, and Pectinex Ultra SP-L achieved the 78.9 % sugar conversion rate at a substrate concentration of 4 % (w/v). Lactiplantibacillus plantarum WiKim0126-induced fermentation with a 4 % solid loading yielded a lactic acid concentration of 22.8 g/L (99.6 % of the theoretical maximum yield) and productivity of 0.95 g/L/h within 24 h. These findings highlight the viability of coffee waste as an eco-friendly resource for sustainable lactic acid production.
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Affiliation(s)
- Seulbi Kim
- Technology Innovation Research Division, World Institute of Kimchi, Gwangju, Republic of Korea; Department of Agricultural Chemistry, Chonnam National University, Gwangju 61186, Republic of Korea
| | - Jong-Cheol Kim
- Technology Innovation Research Division, World Institute of Kimchi, Gwangju, Republic of Korea
| | - Yeong Yeol Kim
- Technology Innovation Research Division, World Institute of Kimchi, Gwangju, Republic of Korea; Department of Integrative Food, Bioscience and Biotechnology, Chonnam National University, Gwangju 61186, Republic of Korea
| | - Jung Eun Yang
- Technology Innovation Research Division, World Institute of Kimchi, Gwangju, Republic of Korea
| | - Hee Min Lee
- Kimchi Industry Promotion Division, World Institute of Kimchi, Gwangju 61755, Republic of Korea
| | - In Min Hwang
- Technology Innovation Research Division, World Institute of Kimchi, Gwangju, Republic of Korea
| | - Hae Woong Park
- Technology Innovation Research Division, World Institute of Kimchi, Gwangju, Republic of Korea
| | - Ho Myeong Kim
- Technology Innovation Research Division, World Institute of Kimchi, Gwangju, Republic of Korea.
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Liu Y, Lu Y, Quan Liu S. Untargeted LC-QTOF-MS/MS-based metabolomics of spent coffee grounds alcoholic beverages fermented with Lachancea thermotolerans and Lactiplantibacillus plantarum. Food Res Int 2023; 167:112733. [PMID: 37087284 DOI: 10.1016/j.foodres.2023.112733] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2022] [Revised: 03/11/2023] [Accepted: 03/17/2023] [Indexed: 03/29/2023]
Abstract
Spent coffee grounds (SCG) is a solid waste generated from coffee brewing. We recently developed a novel SCG hydrolysate-derived alcoholic beverage fermented with Lachancea thermotolerans Concerto and Lactiplantibacillus plantarum ML Prime. To further understand the potential health benefits of the fermented SCG hydrolysate alcoholic beverage, an untargeted metabolomics-based approach (UPLC-QTOF-MS/MS) was applied to detect and identify bioactive metabolites especially low molecular weight compounds. Our results showed that, compared to yeast monoculture-fermented SCG alcoholic beverages, yeast-lactic acid bacterial coculture enriched the beverage with a range of bioactive compounds especially aromatic and branched-chain amino acid derivatives (e.g., 4-hydroxyphenyl lactic acid, phenyl lactic acid, indole lactic acid, (S)-(-)-2-hydroxyisocaproic acid, and 4-hydroxyphenyl ethanol). Although some endogenous phenolic compounds were metabolized during fermentation, many phenolic metabolites (e.g., vinyl phenols, dihydrocaffeic acid, 3,4-dihydroxybenzoic acid, 4-hydroxycoumarin) were produced. Our study provided a theoretical basis for further valorization of SCG hydrolysates from the health benefits point of view and the findings may be extended to other fermented products.
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Titiri E, Filippi K, Giannakis N, Vlysidis A, Koutinas A, Stylianou E. Optimisation of alkaline pretreatment of spent coffee grounds for microbial oil production by Cryptococcus curvatus. Biochem Eng J 2023. [DOI: 10.1016/j.bej.2023.108841] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
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Chauhan S, Mitra S, Yadav M, Kumar A. Microbial production of lactic acid using organic wastes as low-cost substrates. PHYSICAL SCIENCES REVIEWS 2023. [DOI: 10.1515/psr-2022-0159] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
Abstract
Lactic acid is a natural organic acid with diverse of applications in food, pharmaceutical, cosmetics, and chemical industry. Recently, the demand of lactic acid has been grown due to its utilization for polylactic acid production. Microbial production of lactic acid production is preferable due to optical purity of product, utilization of low cost substrates, and low energy requirement. Lignocellulosic biomass and other organic wastes are considered potential raw materials for cost-effective production of lactic acid. The raw materials are either hydrolyzed by enzymes or dilute acids to release the reducing sugars that are fermented in to lactic acid. This review has been focussed on microbial production of lactic acid using different organic wastes as low cost substrate.
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Affiliation(s)
- Sushmita Chauhan
- Department of Biotechnology, School of Engineering and Technology , Sharda University , Greater Noida , India
| | - Shreya Mitra
- Department of Biotechnology, School of Engineering and Technology , Sharda University , Greater Noida , India
| | - Mukesh Yadav
- Department of Biotechnology , Maharishi Markandeshwar (Deemed to be University) , Mullana-Ambala , Haryana , India
| | - Amit Kumar
- Department of Biotechnology, School of Engineering and Technology , Sharda University , Greater Noida , India
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Kang BJ, Jeon JM, Bhatia SK, Kim DH, Yang YH, Jung S, Yoon JJ. Two-Stage Bio-Hydrogen and Polyhydroxyalkanoate Production: Upcycling of Spent Coffee Grounds. Polymers (Basel) 2023; 15:polym15030681. [PMID: 36771983 PMCID: PMC9919241 DOI: 10.3390/polym15030681] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2022] [Revised: 01/20/2023] [Accepted: 01/20/2023] [Indexed: 01/31/2023] Open
Abstract
Coffee waste is an abundant biomass that can be converted into high value chemical products, and is used in various renewable biological processes. In this study, oil was extracted from spent coffee grounds (SCGs) and used for polyhydroxyalkanoate (PHA) production through Pseudomonas resinovorans. The oil-extracted SCGs (OESCGs) were hydrolyzed and used for biohydrogen production through Clostridium butyricum DSM10702. The oil extraction yield through n-hexane was 14.4%, which accounted for 97% of the oil present in the SCGs. OESCG hydrolysate (OESCGH) had a sugar concentration of 32.26 g/L, which was 15.4% higher than that of the SCG hydrolysate (SCGH) (27.96 g/L). Hydrogen production using these substrates was 181.19 mL and 136.58 mL in OESCGH and SCGH media, respectively. The consumed sugar concentration was 6.77 g/L in OESCGH and 5.09 g/L in SCGH media. VFA production with OESCGH (3.58 g/L) increased by 40.9% compared with SCGH (2.54 g/L). In addition, in a fed-batch culture using the extracted oil, cell dry weight was 5.4 g/L, PHA was 1.6 g/L, and PHA contents were 29.5% at 24 h.
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Affiliation(s)
- Beom-Jung Kang
- Green & Sustainable Materials R&D Department, Korea Institute of Industrial Technology (KITECH), Chunan-si 31056, Republic of Korea
| | - Jong-Min Jeon
- Green & Sustainable Materials R&D Department, Korea Institute of Industrial Technology (KITECH), Chunan-si 31056, Republic of Korea
| | - Shashi Kant Bhatia
- Department of Biological Engineering, Konkuk University, Seoul 27478, Republic of Korea
| | - Do-Hyung Kim
- Sustainable Technology and Wellness R&D Group, Korea Institute of Industrial Technology (KITECH), Jeju-si 63243, Republic of Korea
| | - Yung-Hun Yang
- Department of Biological Engineering, Konkuk University, Seoul 27478, Republic of Korea
| | - Sangwon Jung
- Department of Bio and Fermentation Convergence Technology, Kookmin University, Seoul 02707, Republic of Korea
| | - Jeong-Jun Yoon
- Green & Sustainable Materials R&D Department, Korea Institute of Industrial Technology (KITECH), Chunan-si 31056, Republic of Korea
- Correspondence: ; Tel.: +82-41-589-8266
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García-Roldán A, Piriou L, Jauregi P. Natural deep eutectic solvents as a green extraction of polyphenols from spent coffee ground with enhanced bioactivities. FRONTIERS IN PLANT SCIENCE 2023; 13:1072592. [PMID: 36714731 PMCID: PMC9874221 DOI: 10.3389/fpls.2022.1072592] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 10/17/2022] [Accepted: 12/19/2022] [Indexed: 06/18/2023]
Abstract
Conventional extraction techniques are usually based on highly pollutant and/or flammable organic solvents. Therefore, alternative environmentally friendly extraction methods are of particular interest for the recovery of bioactive compounds for their application as food ingredients and/or nutraceuticals. Natural deep eutectic solvents (NADES) are a green and nontoxic attractive alternative to hydroalcoholic extraction. NADES media primarily depends on the intermolecular interactions (hydrogen bonding) among their components to form a eutectic mixture with a much lower final melting point than its individual components. Examples of natural deep eutectic NADES solvents include aqueous solutions (25%-50% water) of choline chloride, sugars, and polyols. This study aimed to investigate the application of two NADES, namely, betaine:triethylene glycol (Bet : TEG) and choline chloride:1,2-propanediol (Chol : Prop), as sustainable green solvents for the extraction of polyphenols from spent coffee ground (SCG), a by-product of coffee processing. In particular, the extraction yield and selectivity were evaluated and compared with conventional green extractions (hot water and a hydroalcoholic solution). In addition, the effect of NADES on the antioxidant and antimicrobial activity of the extracts was investigated. The main outcomes were as follows: (i) NADES were as effective as other conventional green solvents in the extraction of polyphenols with the added advantage of operating at milder temperature conditions, without flammable solvents and with sustainable and natural compounds; (ii) the antimicrobial activity of the NADES extracts was 10 times higher than that of the ethanolic and aqueous extracts. Given the low toxicity of NADES, they could be used as formulation aid for food ingredients.
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Affiliation(s)
- Aitor García-Roldán
- AZTI member of, Food Research, Basque Research and Technology Alliance (BRTA), Derio-Bizkaia, Spain
| | - Léa Piriou
- Polytech’Lille - Génie Biologique et Alimentaire, Université de Lille, Villeneuve d’Ascq, France
| | - Paula Jauregi
- AZTI member of, Food Research, Basque Research and Technology Alliance (BRTA), Derio-Bizkaia, Spain
- Ikerbasque, Basque Foundation for Science, Bilbao, Spain
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Xie M, Xu L, Wu K, Wen Y, Jiang H, Jiang Z. Rheology and microstructure effects of waste spent coffee grounds in modifying asphalt binder. LOW-CARBON MATERIALS AND GREEN CONSTRUCTION 2023. [PMCID: PMC9889243 DOI: 10.1007/s44242-022-00004-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
Herein the biowaste by-product spent coffee grounds (SCGs) from coffee industry were incorporated into asphalt binders for performance enhancement. From the analysis of Fourier transform infrared spectroscopy (FTIR), differential scanning calorimetry (DSC), dynamic shear rheometer (DSR), and Brookfield viscosity rheometer, it is confirmed that SCGs have potential prospects as bio-waste modifiers in the application of sustainable pavements. Results demonstrated that the modification process was mainly based on physical reinforcement. Compared with that of the neat asphalt, the shearing stress-resistant ability and high-temperature performance of the SCGs modified binders with the appropriate addition presented a bit of improvement; whereas the binders with 1% and 3% SCGs exhibited remarkably enhanced low-temperature stability. However, notable weaknesses of practical performance were shown for the binder with excessive content of SCGs, indicating the necessity of proportion selecting before application.
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Affiliation(s)
- Mingjun Xie
- Key Laboratory of Advanced Civil Engineering Materials of Ministry of Education, School of Materials Science and Engineering, Tongji University, Shanghai, 201804 China
| | - Linglin Xu
- Key Laboratory of Advanced Civil Engineering Materials of Ministry of Education, School of Materials Science and Engineering, Tongji University, Shanghai, 201804 China
| | - Kai Wu
- Key Laboratory of Advanced Civil Engineering Materials of Ministry of Education, School of Materials Science and Engineering, Tongji University, Shanghai, 201804 China
| | - Yutong Wen
- Key Laboratory of Advanced Civil Engineering Materials of Ministry of Education, School of Materials Science and Engineering, Tongji University, Shanghai, 201804 China
| | - Hongmi Jiang
- Shanghai Pinghe Bilingua,School, Shanghai, 201206 China
| | - Zhengwu Jiang
- Key Laboratory of Advanced Civil Engineering Materials of Ministry of Education, School of Materials Science and Engineering, Tongji University, Shanghai, 201804 China
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Impact of a Pretreatment Step on the Acidogenic Fermentation of Spent Coffee Grounds. Bioengineering (Basel) 2022; 9:bioengineering9080362. [PMID: 36004887 PMCID: PMC9404928 DOI: 10.3390/bioengineering9080362] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2022] [Revised: 07/26/2022] [Accepted: 07/27/2022] [Indexed: 12/26/2022] Open
Abstract
Acidogenic fermentation (AF) is often applied to wastes to produce short-chain organic acids (SCOAs)—molecules with applications in many industries. Spent coffee grounds (SCGs) are a residue from the coffee industry that is rich in carbohydrates, having the potential to be valorized by this process. However, given the recalcitrant nature of this waste, the addition of a pretreatment step can significantly improve AF. In this work, several pretreatment strategies were applied to SCGs (acidic hydrolysis, basic hydrolysis, hydrothermal, microwave, ultrasounds, and supercritical CO2 extraction), evaluated in terms of sugar and inhibitors release, and used in AF. Despite the low yields of sugar extracted, almost all pretreatments increased SCOAs production. Milder extraction conditions also resulted in lower concentrations of inhibitory compounds and, consequently, in a higher concentration of SCOAs. The best results were obtained with acidic hydrolysis of 5%, leading to a production of 1.33 gSCOAs/L, an increase of 185% compared with untreated SCGs.
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Wong YY, Rawindran H, Lim JW, Tiong ZW, Liew CS, Lam MK, Kiatkittipong W, Abdelfattah EA, Oh WD, Ho YC. Attached microalgae converting spent coffee ground into lipid for biodiesel production and sequestering atmospheric CO2 simultaneously. ALGAL RES 2022. [DOI: 10.1016/j.algal.2022.102780] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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10
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Yankov D. Fermentative Lactic Acid Production From Lignocellulosic Feedstocks: From Source to Purified Product. Front Chem 2022; 10:823005. [PMID: 35308791 PMCID: PMC8931288 DOI: 10.3389/fchem.2022.823005] [Citation(s) in RCA: 19] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2021] [Accepted: 01/21/2022] [Indexed: 01/10/2023] Open
Abstract
The second (lignocellulosic biomass and industrial wastes) and third (algal biomass) generation feedstocks gained substantial interest as a source of various value-added chemicals, produced by fermentation. Lactic acid is a valuable platform chemical with both traditional and newer applications in many industries. The successful fractionation, separation, and hydrolysis of lignocellulosic biomass result in sugars’ rich raw material for lactic acid fermentation. This review paper aims to summarize the investigations and progress in the last 5 years in lactic acid production from inexpensive and renewable resources. Different aspects are discussed—the type of raw materials, pretreatment and detoxification methods, lactic acid-producers (bacteria, fungi, and yeasts), use of genetically manipulated microorganisms, separation techniques, different approaches of process organization, as well as main challenges, and possible solutions for process optimization.
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Valorization of Spent Coffee Grounds as Precursors for Biopolymers and Composite Production. Polymers (Basel) 2022; 14:polym14030437. [PMID: 35160428 PMCID: PMC8840223 DOI: 10.3390/polym14030437] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2021] [Revised: 01/14/2022] [Accepted: 01/19/2022] [Indexed: 01/27/2023] Open
Abstract
Spent coffee grounds (SCG) are a current subject in many works since coffee is the second most consumed beverage worldwide; however, coffee generates a high amount of waste (SCG) and can cause environmental problems if not discarded properly. Therefore, several studies on SCG valorization have been published, highlighting its waste as a valuable resource for different applications, such as biofuel, energy, biopolymer precursors, and composite production. This review provides an overview of the works using SCG as biopolymer precursors and for polymer composite production. SCG are rich in carbohydrates, lipids, proteins, and minerals. In particular, carbohydrates (polysaccharides) can be extracted and fermented to synthesize lactic acid, succinic acid, or polyhydroxyalkanoate (PHA). On the other hand, it is possible to extract the coffee oil and to synthesize PHA from lipids. Moreover, SCG have been successfully used as a filler for composite production using different polymer matrices. The results show the reasonable mechanical, thermal, and rheological properties of SCG to support their applications, from food packaging to the automotive industry.
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Scientometric Overview of Coffee By-Products and Their Applications. Molecules 2021; 26:molecules26247605. [PMID: 34946683 PMCID: PMC8707742 DOI: 10.3390/molecules26247605] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2021] [Revised: 12/08/2021] [Accepted: 12/11/2021] [Indexed: 12/03/2022] Open
Abstract
As coffee consumption is on the rise, and the global coffee production creates an excess of 23 million tons of waste per year, a revolutionary transition towards a circular economy via the transformation and valorization of the main by-products from its cultivation and preparation (Coffee Husk (CH), Coffee Pulp (CP), Coffee Silverskin (CS), and Spent Coffee Grounds (SCG)) is inspiring researchers around the world. The recent growth of scholarly publications in the field and the emerging applications of coffee by-products published in these scientific papers encourages a systematic review to identify the knowledge structure, research hotspots, and to discuss the challenges and future directions. This paper displays a comprehensive scientometric analysis based on 108 articles with a high level of influence in the field of coffee by-products and their applications. According to our analysis, the research in this field shows an explosive growth since 2017, clustered in five core applications: bioactive compounds, microbial transformation, environmental applications, biofuels from thermochemical processes, and construction materials.
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Liu Y, Seah RH, Abdul Rahaman MS, Lu Y, Liu SQ. Concurrent inoculations of Oenococcus oeni and Lachancea thermotolerans: Impacts on non-volatile and volatile components of spent coffee grounds hydrolysates. Lebensm Wiss Technol 2021. [DOI: 10.1016/j.lwt.2021.111795] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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Liu Y, Lu Y, Liu SQ. The potential of spent coffee grounds hydrolysates fermented with Torulaspora delbrueckii and Pichia kluyveri for developing an alcoholic beverage: The yeasts growth and chemical compounds modulation by yeast extracts. Curr Res Food Sci 2021; 4:489-498. [PMID: 34382007 PMCID: PMC8332367 DOI: 10.1016/j.crfs.2021.07.004] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2021] [Revised: 07/14/2021] [Accepted: 07/14/2021] [Indexed: 10/26/2022] Open
Abstract
This study evaluated the effects of yeast extracts (YE) addition (0 % and 0.25 %, w/v) on the no-volatile and volatile compounds of spent coffee grounds (SCG) hydrolysates fermented with single-cultures of two non-Saccharomyces wine yeasts, Torulaspora delbrueckii and Pichia kluyveri. The added YE improved the growth of both T. delbrueckii and P. kluyveri, especially P. kluyveri, resulting in higher ethanol production (1.98 % vs 1.47 %, v/v) by the latter yeast. In addition, the added YE did not impact on most of the alkaloids production regardless of yeast type, while significantly decreasing the contents of chlorogenic, and caffeic acids in SCG hydrolysates fermented with P. kluyveri. Furthermore, more odor-active compounds such as acetate esters and 2-phenylethyl alcohol were produced when YE was added, and P. kluyveri generated significantly higher amounts of esters compared to that of T. delbrueckii. Moreover, YE addition showed a more noticeable effect on the fermentation performance of P. kluyveri relative to that of T. delbrueckii. These findings indicated the potential of SCG hydrolysates fermented with evaluated non-Saccharomyces yeasts and may expand the applications on utilizing SCG to develop new value-added alcoholic products.
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Affiliation(s)
- Yunjiao Liu
- Department of Food Science and Technology, Science Drive 2, Faculty of Science, National University of Singapore, 117542, Singapore
| | - Yuyun Lu
- Department of Food Science and Technology, Science Drive 2, Faculty of Science, National University of Singapore, 117542, Singapore
| | - Shao Quan Liu
- Department of Food Science and Technology, Science Drive 2, Faculty of Science, National University of Singapore, 117542, Singapore.,National University of Singapore (Suzhou) Research Institute, 377 Lin Quan Street, Suzhou Industrial Park, Jiangsu, 215123, China
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Abstract
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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Statistical Optimization of Alkali Pretreatment to Improve Sugars Recovery from Spent Coffee Grounds and Utilization in Lactic Acid Fermentation. Processes (Basel) 2021. [DOI: 10.3390/pr9030494] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
Biorefinery, which utilizes carbon-neutral biomass as a resource, is attracting attention as a significant alternative in a modern society confronted with climate change. In this study, spent coffee grounds (SCGs) were used as the feedstock for lactic acid fermentation. In order to improve sugar conversion, alkali pretreatment was optimized by a statistical method, namely response surface methodology (RSM). The optimum conditions for the alkali pretreatment of SCGs were determined as follows: 75 °C, 3% potassium hydroxide (KOH) and a time of 2.8 h. The optimum conditions for enzymatic hydrolysis of pretreated SCGs were determined as follows: enzyme complex loading of 30-unit cellulase, 15-unit cellobiase and 50-unit mannanase per g biomass and a reaction time of 96 h. SCG hydrolysates were used as the carbon source for Lactobacillus cultivation, and the conversions of lactic acid by L. brevis ATCC 8287 and L. parabuchneri ATCC 49374 were 40.1% and 55.8%, respectively. Finally, the maximum lactic acid production by L. parabuchneri ATCC 49374 was estimated to be 101.2 g based on 1000 g of SCGs through the optimization of alkali pretreatment and enzymatic hydrolysis.
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Hejna A. Potential applications of by-products from the coffee industry in polymer technology - Current state and perspectives. WASTE MANAGEMENT (NEW YORK, N.Y.) 2021; 121:296-330. [PMID: 33406477 DOI: 10.1016/j.wasman.2020.12.018] [Citation(s) in RCA: 20] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/15/2020] [Revised: 12/09/2020] [Accepted: 12/12/2020] [Indexed: 06/12/2023]
Abstract
Coffee is one of the most popular beverages in the world, and its popularity is continuously growing, which can be expressed by almost doubling production over the last three decades. Cultivation, processing, roasting, and brewing coffee are known for many years. These processes generate significant amounts of by-products since coffee bean stands for around 50% of the coffee cherry. Therefore, considering the current pro-ecological trends, it is essential to develop the utilization methods for the other 50% of the coffee cherry. Among the possibilities, much attention is drawn to polymer chemistry and technology. This industry branch may efficiently consume different types of lignocellulosic materials to use them as fillers for polymer composites or as intermediate sources of particular chemical compounds. Moreover, due to their chemical composition, coffee industry by-products may be used as additives modifying the oxidation resistance, antimicrobial, or antifungal properties of polymeric materials. These issues should be considered especially important in the case of biodegradable polymers, whose popularity is growing over the last years. This paper summarizes the literature reports related to the generation and composition of the coffee industry by-products, as well as the attempts of their incorporation into polymer technology. Moreover, potential directions of research based on the possibilities offered by the coffee industry by-products are presented.
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Affiliation(s)
- Aleksander Hejna
- Department of Polymer Technology, Gdańsk University of Technology, Narutowicza 11/12, 80-233 Gdańsk, Poland.
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19
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Kopp D, Willows RD, Sunna A. Cell-Free Enzymatic Conversion of Spent Coffee Grounds Into the Platform Chemical Lactic Acid. Front Bioeng Biotechnol 2019; 7:389. [PMID: 31850336 PMCID: PMC6901390 DOI: 10.3389/fbioe.2019.00389] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2019] [Accepted: 11/19/2019] [Indexed: 12/23/2022] Open
Abstract
The coffee industry produces over 10 billion kg beans per year and generates high amounts of different waste products. Spent coffee grounds (SCG) are an industrially underutilized waste resource, which is rich in the polysaccharide galactomannan, a polysaccharide consisting of a mannose backbone with galactose side groups. Here, we present a cell-free reaction cascade for the conversion of mannose, the most abundant sugar in SCG, into L-lactic acid. The enzymatic conversion is based on a so far unknown oxidative mannose metabolism from Thermoplasma acidophilum and uses a previously characterized mannonate dehydratase to convert mannose into lactic acid via 4 enzymatic reactions. In comparison to known in vivo metabolisms the bioconversion is free of phosphorylated intermediates and cofactors. Assessment of enzymes, adjustment of enzyme loadings, substrate and cofactor concentrations, and buffer ionic strength allowed the identification of crucial reaction parameters and bottlenecks. Moreover, reactions with isotope labeled mannose enabled the monitoring of pathway intermediates and revealed a reverse flux in the conversion process. Finally, 4.4 ± 0.1 mM lactic acid was produced from 14.57 ± 0.7 mM SCG-derived mannose. While the conversion efficiency of the process can be further improved by enzyme engineering, the reaction demonstrates the first multi-enzyme cascade for the bioconversion of SCG.
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Affiliation(s)
- Dominik Kopp
- Department of Molecular Sciences, Macquarie University, Sydney, NSW, Australia
| | - Robert D Willows
- Biomolecular Discovery and Design Research Centre, Macquarie University, Sydney, NSW, Australia
| | - Anwar Sunna
- Department of Molecular Sciences, Macquarie University, Sydney, NSW, Australia.,Biomolecular Discovery and Design Research Centre, Macquarie University, Sydney, NSW, Australia
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Massaya J, Prates Pereira A, Mills-Lamptey B, Benjamin J, Chuck CJ. Conceptualization of a spent coffee grounds biorefinery: A review of existing valorisation approaches. FOOD AND BIOPRODUCTS PROCESSING 2019. [DOI: 10.1016/j.fbp.2019.08.010] [Citation(s) in RCA: 36] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
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Lactic Acid Production from a Whole Slurry of Acid-Pretreated Spent Coffee Grounds by Engineered Saccharomyces cerevisiae. Appl Biochem Biotechnol 2019; 189:206-216. [DOI: 10.1007/s12010-019-03000-6] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/26/2018] [Accepted: 03/27/2019] [Indexed: 10/27/2022]
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Stylianou M, Agapiou A, Omirou M, Vyrides I, Ioannides IM, Maratheftis G, Fasoula D. Converting environmental risks to benefits by using spent coffee grounds (SCG) as a valuable resource. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2018; 25:35776-35790. [PMID: 29860699 DOI: 10.1007/s11356-018-2359-6] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/15/2017] [Accepted: 05/22/2018] [Indexed: 06/08/2023]
Abstract
Coffee is perhaps one of the most vital ingredients in humans' daily life in modern world. However, this causes the production of million tons of relevant wastes, i.e., plastic cups, aluminum capsules, coffee chaff (silver skin), and spent coffee grounds (SCG), all thrown untreated into landfills. It is estimated that 1 kg of instant coffee generates around 2 kg of wet SCG; a relatively unique organic waste stream, with little to no contamination, separated directly in the source by the coffee shops. The produced waste has been under researchers' microscope as a useful feedstock for a number of promising applications. SCG is considered a valuable, nutrients rich source of bioactive compounds (e.g., phenolics, flavonoids, carotenoids, lipids, chlorogenic and protocatechuic acid, melanoidins, diterpenes, xanthines, vitamin precursors, etc.) and a useful resource material in other processes (e.g., soil improver and compost, heavy metals absorbent, biochar, biodiesel, pellets, cosmetics, food, and deodorization products). This paper aims to provide a holistic approach for the SCG waste management, highlighting a series of processes and applications in environmental solutions, food industry, and agricultural sector. Thus, the latest developments and approaches of SCG waste management are reviewed and discussed.
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Affiliation(s)
- Marinos Stylianou
- NIREAS-International Research Center, Department of Civil and Environmental Engineering, University of Cyprus, P.O. Box 20537, CY-1678, Nicosia, Cyprus.
| | - Agapios Agapiou
- Department of Chemistry, University of Cyprus, P.O. Box 20537, CY-1678, Nicosia, Cyprus
| | - Michalis Omirou
- Agricultural Research Institute, P.O. Box 22016, CY-1516, Nicosia, Cyprus
| | - Ioannis Vyrides
- Department of Environmental Science and Technology, Cyprus University of Technology, 30 Archbishop Kyprianos, CY-3036, Lemesos, Cyprus
| | | | - Grivas Maratheftis
- Agricultural Research Institute, P.O. Box 22016, CY-1516, Nicosia, Cyprus
| | - Dionysia Fasoula
- Agricultural Research Institute, P.O. Box 22016, CY-1516, Nicosia, Cyprus
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Kovalcik A, Obruca S, Marova I. Valorization of spent coffee grounds: A review. FOOD AND BIOPRODUCTS PROCESSING 2018. [DOI: 10.1016/j.fbp.2018.05.002] [Citation(s) in RCA: 82] [Impact Index Per Article: 13.7] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
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