Overview of single cell protein: Production pathway, sustainability outlook, and digital twin potentials.

Single-cell protein (SCP) is an evolving biotechnological concept that can potentially align protein production with the global sustainability commitment. This review presents an overview of SCP's current outlook, including production, commercial prospects, and sustainability status. It also elaborates on the potential of the evolving digital twin concept in improving SCP production's efficiency and sustainability performance. An expanding body of work was identified, with well-explored fermentative approaches and varying substrates and microbes. Whereas interest in first-generation substrates such as methane is gradually fading due to their high competitiveness and acquisition cost, second-generation substrates such as lignocellulosic materials and agro-industrial wastes are rapidly evolving due to their availability, low cost, appreciable nutrient density, and alignment with the circular bioeconomy path. Sustainability assessment of current production attaches substantial environmental, mainly global warming and land use offset, and economic savings to SCP production. Moreover, it emphasizes conventional energy use as a hotspot contributor to all impact categories. However, research on life cycle costing, social life cycle assessment, and environmental nutrition concepts is limited. Current trends project rapid market growth for SCP due to expanding feed, food, and nonfood applications. The rapid influx of transformative innovations such as mixed culture biotechnology and the emerging digital twin concept that present catalytic advantages in achieving market growth and sustainability cobenefits are backing these projections. Several sensor and predictive technologies are available to enable an SCP-digital twin path, presenting an opportunity to enhance green and precision SCP production. Despite these innovations, significant efforts are required to overcome limitations concerning toxicity, legislative restrictions, technical constraints, and consumer neophobia to bolster commerce and market value. [Display omitted] • Agro-industrial waste upcycling should frontline circular bioeconomy actions for value recovery. • Single Cell Protein production can align protein supply with global sustainability commitment. • Closing sustainability loop in pulse protein extraction with single cell protein pathway. • Combine environment, economic, social, and nutrition metrics in single cell protein assessment. • Adopt digital twin to for better control and optimization of single cell protein production. [ABSTRACT FROM AUTHOR]