As Earth’s fossil energy resources are limited, there is a growing need for renewable resources such as biodiesel. That is the reason why the social, economic and environmental impacts of biofuels became an important research topic in the last decade. Depleted stocks of crude oil and the significant level of environmental pollution encourage researchers and professionals to seek and find solutions. The study aims to analyze the economic and sustainability issues of biodiesel production by a systematic literature review. During this process, 53 relevant studies were analyzed out of 13,069 identified articles. Every study agrees that there are several concerns about the first-generation technology; however, further generations cannot be price-competitive at this moment due to the immature technology and high production costs. However, there are promising alternatives, such as wastewater-based microalgae with up to 70% oil content, fat, oils and grease (FOG), when production cost is below 799 USD/gallon, and municipal solid waste-volatile fatty acids technology, where the raw material is free. Proper management of the co-products (mainly glycerol) is essential, especially at the currently low petroleum prices (0.29 USD/L), which can only be handled by the biorefineries. Sustainability is sometimes translated as cost efficiency, but the complex interpretation is becoming more common. Common elements of sustainability are environmental and social, as well as economic, issues.

Today, reducing GHG emissions is an important goal worldwide. Initially, first-generation biofuels were considered as a solution; however, they created a conflict between food and fuel. Advanced biofuels, which use non-edible materials, have emerged and are becoming more widespread, thus resolving this conflict. The paper aimed to investigate the three pillars of advanced biofuels’ sustainability (economic, environmental, and social). In the frame of a systematic literature review, 41 out of the initially screened 3407 articles were analyzed in depth. The economic aspect of sustainability was the most frequently occurring topic, followed by the environmental aspect, while the number of articles related to the social aspect was limited. From the economic point of view, all the analyzed articles agreed that advanced biofuels are far from commercialization at this stage; however, there are promising options related to different feedstocks or production technologies. Advanced biofuels perform unequivocally better environmentally than even conventional biofuels. For third-generation biofuels, negative net GHG emissions can even be possible, while fourth-generation biofuels can theoretically be produced from CO₂. With respect to the social pillar, job creation was the core element of the articles analyzed. This can be experienced at the farm, production, and research levels. Although the commercialization of advanced biofuel production will take time, humanity must turn to them in order to avoid the food versus fuel problem, as well as to successfully fight against climate change and global warming.

The COVID-19 crisis has disrupted economies and societies and the sustainability characteristics of agri-food due to a significant decline in turnover, difficulties in transportation, and changes in market and contact habits. An analysis was carried out using the PRISMA protocol and the Scopus, Web of Science, and Science Direct electronic databases. The aim of this research is to present the main research issues in agri-food sustainability (economic, environmental, and social issues) in the pre-COVID-19 period, to compare it with the research trends in the COVID-19 period, and to explore the influence of the epidemic. This research looks for research gaps and possible future research directions. Research before COVID-19 was primarily concerned with environmental and economic sustainability. The main focus areas were business development and environmental issues. During COVID-19, the focus shifted to economic sustainability. Survival was the primary issue. The main research areas were financial, inventory, waste management, and innovation issues. Food safety and digitalisation were highlighted. Precision agriculture, short food supply chains, and collaboration increased efficiency. The role of trust has increased. The COVID-19 experience is valuable for almost all disciplines. Policy, health, and economic decision-makers can apply better solutions to future crises.