Nutritious foods are essential for human health and development. However, malnutrition and hidden hunger continue to be a challenge globally. In most developing countries, access to adequate and nutritious food continues to be a challenge. Although hidden hunger is less prevalent in developed countries compared to developing countries where iron (Fe) and zinc (Zn) deficiencies are common. The United Nations (UN) 2nd Sustainable Development Goal was set to eradicate malnutrition and hidden hunger. Hidden hunger has led to numerous cases of infant and maternal mortalities, and has greatly impacted growth, development, cognitive ability, and physical working capacity. This has influenced several countries to develop interventions that could help combat malnutrition and hidden hunger. Interventions such as dietary diversification and food supplementation are being adopted. However, fortification but mainly biofortification has been projected to be the most sustainable solution to malnutrition and hidden hunger. Plant-based foods (PBFs) form a greater proportion of diets in certain populations; hence, fortification of PBFs is relevant in combating malnutrition and hidden hunger. Agronomic biofortification, plant breeding, and transgenic approaches are some currently used strategies in food crops. Crops such as cereals, legumes, oilseeds, vegetables, and fruits have been biofortified through all these three strategies. The transgenic approach is sustainable, efficient, and rapid, making it suitable for biofortification programs. Omics technology has also been introduced to improve the efficiency of the transgenic approach.

Globally, the production, distribution, sale and consumption of plant-based foods (PBFs) are on the increase due to heightened consumer awareness, a growing demand for clean label products, widespread efforts to promote and embrace sustainable practices, and ethical concerns over animal-derived counterparts. This has led to the exploration of several strategies by researchers and the food industry to develop alternative milk, cheese, meat, and egg products from various plant-based sources using technologies such as precision fermentation (PF), scaffolding, extrusion, and muscle fibre simulation. This work explores current alternative protein sources and PBFs, production trends, innovations in formulation, nutritional quality, as well as challenges restricting full utilization and other limitations. However, PBFs have several limitations which constrain their acceptance, including the beany flavour of legumes, concerns about genetically modified foods, cost, nutritional inadequacies associated micronutrient deficiencies, absence of safety regulations, and the addition of ingredients that are contrary to their intended health-promoting purpose. The review concludes that investing in the development of PBFs now, has the potential to facilitate a rapid shift to large scale consumption of sustainable and healthy diets in the near future. Graphical Abstract

Background: Increased awareness of the relationship between certain components in food beyond basic nutrition and health has generated interest in the production and consumption. Functional foods owe much of their health benefits to the presence of bioactive components. Despite their importance, their poor stability, solubility, and bioavailability may require the use of different strategies including nano-delivery systems (NDS) to sustain delivery and protection during handling, storage, and ingestion. Moreover, increasing consumer trend for non-animal sourced ingredients and interest in sustainable production invigorate the need to evaluate the utility of plant-based NDS. Method: In the present study, 129 articles were selected after screening from Google Scholar searches using key terms from current literature. Scope: This review provides an overview of current trends in the use of bioactive compounds as health-promoting ingredients in functional foods and the main methods used to stabilize these components. The use of plant proteins as carriers in NDS for bioactive compounds and the merits and challenges of this approach are also explored. Finally, the review discusses the application of protein-based NDS in food product development and highlights challenges and opportunities for future research. Key Findings: Plant-based NDS is gaining recognition in food research and industry for their role in improving the shelf life and bioavailability of bioactives. However, concerns about safety and possible toxicity limit their widespread application. Future research efforts that focus on mitigating or enhancing their safety for food applications is warranted.