Heavy crude oil and bitumen resources are more than double the conventional light oil reserves worldwide. Heavy crude oil and bitumen production is on average twice as capital and energy intensive as the production of conventional oil. This is because of their extremely low mobility due to high viscosity at reservoir conditions alongside the presence of undesirable components such as asphaltenes, heavy metals and sulphur making it more challenging to produce, transport as well as refine. It is well know that pipelines are the most convenient means of transporting crude oil from the producing field to the refinery. However, moving heavy crude oil and bitumen is extremely challenging because of their inability to flow freely. As such, without prior reduction in the heavy crude oil and bitumen viscosity, transportation via pipeline is difficult. This is because of the huge energy (i.e. high pumping power) required to overcome the high-pressure drop in the pipeline due to their high viscosity at reservoir conditions. To reduce this high-pressure drop and cost of transportation, several technologies have been proposed to improve the flow properties of the heavy crude oil and bitumen through pipelines. In this study, different technologies are reviewed and the advantages and disadvantages of each technology are highlighted with the view that the review will provide direction for improvement and development of novel technologies for bitumen and heavy oil transportation via pipelines.

The world’s population is expected to grow at an increasing rate, leading to increased food consumption and waste production. Even though food waste represents one of the most challenging economic and environmental issues of the 21st century, it also provides a vast array of valuable resources. To address the challenge, this study uses resource recovery from food waste to close the supply chain loop, which is the cornerstone of a circular economy. By applying the bibliometric review technique, trends and patterns in food waste and circular economy were studied. The analysis of frequent keywords in the field provided insights into further research directions. A Boolean search of the keywords in the Scopus database resulted in 288 articles, published between 2015 and 2021. Further screening of titles, keywords, and abstracts resulted in 155 journal articles. Bibliometric coupling, including authors’ co-citation data, co-occurrence, and the occurrence of keywords, was graphically mapped using VOSviewer software. From the analysis of the publications, eight broad themes emerged: (1) anaerobic digestion of food waste for circular economy creation; (2) food waste systems and life cycle assessments for circular economy; (3) bio-based circular economy approaches; (4) consumer behavior and attitudes toward circular economies; (5) food supply chains and food waste in a circular economy; (6) material flow analysis and sustainability; (7) challenges, policies, and practices to achieve circularity; and (8) circular economy and patterns of consumption. Based on the eight themes, we emphasize an urgent need to promote the collaboration of governments, the private sector, educational institutions, and researchers, who should combine efforts to promote, integrate and accelerate acceptance of circularity, which will potentially mitigate greenhouse emissions associated with food loss and waste. We also highlight an opportunity to encourage consumer acceptance of upcycled food in the food waste hierarchy. In addition, we deduce that there is a need to quantify food waste and emissions of greenhouse gases due to this waste along the food value chain; this is important as it is one pathway of examining the ‘food leaks’ along the food supply chain. This can then inform optimal strategies targeting specific areas of the food supply chain experiencing food leaks. Lastly, food wastage affects the entire globe; however, future studies and funding need to be channeled towards investigating the possibility of implementing circularity in developing countries.

Changing consumers’ taste for chemical and thermally processed food and preference for perceived healthier minimally processed alternatives is a challenge to food industry. At present, several technologies have found usefulness as choice methods for ensuring that processed food remains unaltered while guaranteeing maximum safety and protection of consumers. However, the effectiveness of most green technology is limited due to the formation of resistant spores by certain foodborne microorganisms and the production of toxins. Cold plasma, a recent technology, has shown commendable superiority at both spore inactivation and enzymes and toxin deactivation. However, the exact mechanism behind the efficiency of cold plasma has remained unclear. In order to further optimize and apply cold plasma treatment in food processing, it is crucial to understand these mechanisms and possible factors that might limit or enhance their effectiveness and outcomes. As a novel non-thermal technology, cold plasma has emerged as a means to ensure the microbiological safety of food. Furthermore, this review presents the different design configurations for cold plasma applications, analysis the mechanisms of microbial spore and biofilm inactivation, and examines the impact of cold plasma on food compositional, organoleptic, and nutritional quality.

This mini-review reports curbing waste shells (i.e. seashells, eggshells, snail shells, etc.), environmental health issues and liabilities by using them as material for heterogenous catalysts, blended cement manufacture, concrete aggregate, ceramics and plastics additives, biofilter medium and biomedical applications. The traditional materials used in the manufacture of these products could be relatively cheap; however, there are considerable environmental issues (i.e., ecological damage, disruption of eco-system and air contamination) as well as intense energy consumption associated with the exploitation of depleting natural resources. Waste shells are a renewable and cheap alternative, and will simultaneously decrease manufacturing cost while reducing their burden on the environment. This paper emphasizes environmental sustainability by summarizing articles published on various applications of waste shell-derived biomaterials. The properties of waste shell-derived biomaterials are presented and discussed. The materials’ properties suggest they are similar to limestone and their biological–natural origin and the high calcium carbonate content with a trace amount of other mineral elements makes them highly favorable for cement production, heterogenous catalysts and hydroxyapatite manufacture for biomedical and wastewater treatment applications. The purpose of this work is to offer new perspectives and direction for future research on waste shell-derived biomaterials while existing areas of applications demanding scale up are highlighted.

Conventional thermal and chemical treatments used in food preservation have come under scrutiny by consumers who demand minimally processed foods free from chemical agents but microbiologically safe. As a result, antimicrobial peptides (AMPs) such as bacteriocins and nisin that are ribosomally synthesised by bacteria, more prominently by the lactic acid bacteria (LAB) have appeared as a potent alternative due to their multiple biological activities. They represent a powerful strategy to prevent the development of spore-forming microorganisms in foods. Unlike thermal methods, they are natural without an adverse impact on food organoleptic and nutritional attributes. AMPs such as nisin and bacteriocins are generally effective in eliminating the vegetative forms of spore-forming bacteria compared to the more resilient spore forms. However, in combination with other non-thermal treatments, such as high pressure, supercritical carbon dioxide, electric pulses, a synergistic effect with AMPs such as nisin exists and has been proven to be effective in the inactivation of microbial spores through the disruption of the spore structure and prevention of spore outgrowth. The control of microbial spores in foods is essential in maintaining food safety and extension of shelf-life. Thus, exploration of the mechanisms of action of AMPs such as nisin is critical for their design and effective application in the food industry. This review harmonises information on the mechanisms of bacteria inactivation from published literature and the utilisation of AMPs in the control of microbial spores in food. It highlights future perspectives in research and application in food processing.