Thermal hydrolysis pretreatment (THP) has been considered as an advanced approach to enhance the performance of anaerobic digestion treating municipal sludge. However, several drawbacks were also identified with THP including the formation of brown and ultraviolet-quenching compounds that contain recalcitrant dissolved organic nitrogen (rDON). Melanoidins produced from the Maillard reaction between reducing sugar and amino group have been regarded as a representative of such compounds. This review presented the state-of-the-art understanding of the mechanism of melanoidin formation derived from the research of sludge THP, food processing, and model Maillard reaction systems. Special attentions were paid to factors affecting melanoidin formation and their implications to the control of rDON in the sludge THP process. These factors include reactant availability, heating temperature and time, pH, and the presence of metallic ions. It was concluded that efforts need to be focused on elucidating the extent of the Maillard reaction in sludge THP. This paper aims to provide a mechanistic recommendation on the research and control of the THP-resulted rDON in municipal wastewater treatment plants.

• Microfluidization and ultrasonication were utilized to modify pectin. • Modified pectin showed lower particle size, molecular weight and polydispersity. • Modified pectin owned higher DPPH radical scavenging capacity and lower viscosity. • Modified pectin showed higher emulsion stability and interfacial loading. • Modified pectin improved encapsulation functionality to protect vitamin D3.

Plant biomass, the most abundant and sustainable carbon source, offers a rich chemical space to design hard carbons for sodium ion batteries. However, the compositional complexity of biomass has for a long time compromised the predictability of the structural and electrochemical properties of carbon. Using the chemical-enzymatic fractionation technique, we successively remove non-lignocellulosic components, hemicellulose and cellulose to create a suite of precursors for carbonization, in order to understand the roles of each biomass component in battery performance. Brewer's spent grain, an agricultural waste, is used as a representative biomass platform. The resulting hard carbon, with non-lignocellulosic components removed prior to carbonization, exhibits a dramatically reduced surface area and an increased specific capacity. Simultaneously removing non-lignocellulosic components and hemicellulose results in more sp² carbon, expanded (002) interlayer spacing, and a remarkably improved specific capacity by four fold. Further removing cellulose, with only lignin remaining, significantly reduces the sp² carbon and undermines the cycling stability of the derived carbon. Our finding reveals that the electrochemical properties of the biomass-derived hard carbons in sodium ion batteries may be positively correlated with cellulose and lignin but negatively impacted by non-lignocellulosic components and hemicellulose. Guided by this knowledge, we further fractionated two additional biomasses, i.e. grape pomace and walnut shells, for improving the carbon performance. After removing non-lignocellulosic components and hemicellulose, the resulting hard carbon delivers a reversible capacity of 296 mA h g⁻¹ at 50 mA g⁻¹ and retains 86.4% capacity after 200 cycles. Therefore, our results lay the foundation for unlocking the potential of biomass-derived carbon materials by precise fractionation of biomass components.

As the global population approaches 10 billion by 2050, the critical need to ensure food security becomes increasingly pronounced. In response to the urgent problems posed by global population growth, our study adds to the growing body of knowledge in the field of alternative proteins, entomophagy, insect-based bioactive proteolysates, and peptides. It also provides novel insights with essential outcomes for guaranteeing a safe and sustainable food supply in the face of rising global population demands. These results offer insightful information to researchers and policymakers tackling the intricate relationship between population expansion and food supplies. Unfortunately, conventional agricultural practices are proving insufficient in meeting these demands. Pursuing alternative proteins and eco-friendly food production methods has gained urgency, embracing plant-based proteins, cultivated meat, fermentation, and precision agriculture. In this context, insect farming emerges as a promising strategy to upcycle agri-food waste into nutritious protein and fat, meeting diverse nutritional needs sustainably. A thorough analysis was conducted to evaluate the viability of insect farming, investigate insect nutrition, and review the techniques and functional properties of protein isolation. A review of peptide generation from insects was conducted, covering issues related to hydrolysate production, protein extraction, and peptide identification. The study addresses the nutritional value and global entomophagy habits to elucidate the potential of insects as sources of peptides and protein. This inquiry covers protein and hydrolysate production, highlighting techniques and bioactive peptides. Functional properties of insect proteins’ solubility, emulsification, foaming, gelation, water-holding, and oil absorption are investigated. Furthermore, sensory aspects of insect-fortified foods as well as challenges, including Halal and Kosher considerations, are explored across applications. Our review underscores insects’ promise as sustainable protein and peptide contributors, offering recommendations for further research to unlock their full potential.