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Comprehensive Review on Potential Contamination in Fuel Ethanol Production with Proposed Specific Guideline Criteria. ENERGIES 2022. [DOI: 10.3390/en15092986] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
Ethanol is a promising biofuel that can replace fossil fuel, mitigate greenhouse gas (GHG) emissions, and represent a renewable building block for biochemical production. Ethanol can be produced from various feedstocks. First-generation ethanol is mainly produced from sugar- and starch-containing feedstocks. For second-generation ethanol, lignocellulosic biomass is used as a feedstock. Typically, ethanol production contains four major steps, including the conversion of feedstock, fermentation, ethanol recovery, and ethanol storage. Each feedstock requires different procedures for its conversion to fermentable sugar. Lignocellulosic biomass requires extra pretreatment compared to sugar and starch feedstocks to disrupt the structure and improve enzymatic hydrolysis efficiency. Many pretreatment methods are available such as physical, chemical, physicochemical, and biological methods. However, the greatest concern regarding the pretreatment process is inhibitor formation, which might retard enzymatic hydrolysis and fermentation. The main inhibitors are furan derivatives, aromatic compounds, and organic acids. Actions to minimize the effects of inhibitors, detoxification, changing fermentation strategies, and metabolic engineering can subsequently be conducted. In addition to the inhibitors from pretreatment, chemicals used during the pretreatment and fermentation of byproducts may remain in the final product if they are not removed by ethanol distillation and dehydration. Maintaining the quality of ethanol during storage is another concerning issue. Initial impurities of ethanol being stored and its nature, including hygroscopic, high oxygen and carbon dioxide solubility, influence chemical reactions during the storage period and change ethanol’s characteristics (e.g., water content, ethanol content, acidity, pH, and electrical conductivity). During ethanol storage periods, nitrogen blanketing and corrosion inhibitors can be applied to reduce the quality degradation rate, the selection of which depends on several factors, such as cost and storage duration. This review article sheds light on the techniques of control used in ethanol fuel production, and also includes specific guidelines to control ethanol quality during production and the storage period in order to preserve ethanol production from first-generation to second-generation feedstock. Finally, the understanding of impurity/inhibitor formation and controlled strategies is crucial. These need to be considered when driving higher ethanol blending mandates in the short term, utilizing ethanol as a renewable building block for chemicals, or adopting ethanol as a hydrogen carrier for the long-term future, as has been recommended.
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Lu Y, Xu K, Song Y, Zhao Z, Guo M. Effect of thermal processing on the phenolic profiles, antioxidant capacity, and volatile compounds of fig wines. J FOOD PROCESS PRES 2021. [DOI: 10.1111/jfpp.15321] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Affiliation(s)
- Yao Lu
- Key Laboratory of Food Processing Technology and Quality Control in Shandong Province College of Food Science and Engineering Shandong Agricultural University Tai'an China
- Jinan Fruit Research Institute China Supply and Marketing Cooperatives Jinan China
| | - Kang Xu
- Key Laboratory of Food Processing Technology and Quality Control in Shandong Province College of Food Science and Engineering Shandong Agricultural University Tai'an China
| | - Yinghui Song
- Technology and Promotion Center of Grape and Grape Wine in Penglai City Yantai China
| | - Zhengtao Zhao
- College of Light Industry and Food Engineering Guangxi University Nanning China
| | - Mengmeng Guo
- Key Laboratory of Food Processing Technology and Quality Control in Shandong Province College of Food Science and Engineering Shandong Agricultural University Tai'an China
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WEI XF, MA XL, CAO JH, SUN XY, FANG YL. Aroma characteristics and volatile compounds of distilled Crystal grape spirits of different alcohol concentrations: wine sprits in the Shangri-La region of China. FOOD SCIENCE AND TECHNOLOGY 2018. [DOI: 10.1590/fst.12117] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Affiliation(s)
- Xiao-Feng WEI
- College of Enology, China; Shaanxi Engineering Research, China
| | - Xue-Lei MA
- College of Food Science and Pharmacy, China
| | | | - Xiang-Yu SUN
- College of Enology, China; Key Laboratory of Agro-products, China
| | - Yu-Lin FANG
- College of Enology, China; Shaanxi Engineering Research, China
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