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Anaerobic digestion is an efficient technology for a sustainable conversion of various organic wastes such as animal manure, municipal solid waste, agricultural residues and industrial waste into biogas. This technology offers a unique set of benefits, some of which include a good waste management technique, enhancement in the ecology of rural areas, improvement in health through a decrease of pathogens and optimization of the energy consumption of communities. The biogas produced through anaerobic digestion varies in composition, but it consists mainly of carbon dioxide methane together with a low quantity of trace gases. The variation in biogas composition are dependent on some factors namely the substrate type being digested, pH, operating temperature, organic loading rate, hydraulic retention time and digester design. However, the type of substrate used is of greater interest due to the direct dependency of microorganism activities on the nutritional composition of the substrate. Therefore, the aim of this review study is to provide a detailed analysis of the various types of organic wastes that have been used as a substrate for the sustainable production of biogas. Biogas formation from various substrates reported in the literature were investigated, an analysis and characterization of these substrates provided the pro and cons associated with each substrate. The findings obtained showed that the methane yield for all animal manure varied from 157 to 500 mL/gVS with goat and pig manure superseding the other animal manure whereas lignocellulose biomass varied from 160 to 212 mL/gVS. In addition, organic municipal solid waste and industrial waste showed methane yield in the ranges of 143–516 mL/gVS and 25–429 mL/gVS respectively. These variations in methane yield are primarily attributed to the nutritional composition of the various substrates.

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The use of biodegradable packaging material as an alternative to conventional petrochemical-based polymers is based on the environmental issues associated with conventional materials. This review aims to update the existing knowledge regarding the application of starch-based biodegradable films for food packaging. From the review, it was evident that starch stands out among biopolymers due to its abundance and cost effectiveness. This review is the first of its kind, having reviewed over 100 articles/publications on starch-based biodegradable films, consolidating their current state of research and their applications for food packaging; therefore, this review provides an insight into the utilization of nanomaterials to improve the shelf life of packaging of food.

The authors reviewed the future prospects and previous studies on anaerobic digestion technology for biogas production and highlight the solutions to problems relating to construction and maintenance of biogas digesters, which can now be accessed in a single paper. It is the aim of the review to provide insight into the use, process and application of anaerobic digestion as an appropriate technology for biogas production from peer reviewed literature. Recent studies have shown that the microbial communities and metabolic pathways involves in anaerobic digestion are influenced by temperature. Their metabolic activities increase significantly with increase in temperature. Therefore, the findings of the review reveal that temperature is a major parameter for biogas production due to its influence on metabolic activities involved in anaerobic digestion. Hence, there is the need for insulation as well as external heating to maintain temperature stability and to avoid temperature fluctuations. More also, the anaerobic digestion technology for production of biogas is a viable option that can supplement as well as reduce the usage of non-renewable energy sources such as fossil fuel. The detailed information addressed in this study would increase biogas energy mix as well as mitigating climate change. Therefore, the study recommends the use of biogas as a clean energy for the purpose of power generation, cooking and heating.

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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.

It has been the heartbeat of researchers and food engineers to discover the appropriate and effective technology for microbial control to ensure the safety of food. This is because microorganisms such as bacteria, fungi, viruses, and protozoa can cause contamination in food products. Many studies have published reviews on the use of single novel technology such as radio frequency (RF), pulsed light (PL), and cold plasma (CP) to process food to ensure food safety. However, no review has provided a comprehensive, detailed overview of the RF, PL, and CP treatments for pasteurizing food products in one publication. This study aims to review and present the future directions of RF, PL, and CP applications in light of various aspects of these technologies. The review concluded that although no novel technique (thermal or nonthermal) could adequately meet all the requirements for food safety, traditional thermal processes can be extremely useful in reducing and eliminating microbe contamination.However, they cannot be applied to temperature-sensitive foods. Besides inactivating microbial spores, traditional thermal processes can denature proteins as well as organoleptic properties, such as taste, nutritional value, and sensory characteristics, illustrating the importance of these novel technologies as an alternative to heatbased techniques. As a result of this study, hurdle technology is recommended since it has an additive effect and achieves better germicidal results.