Plant-based proteins from agro-industrial waste and by-products: Towards a more circular economy

There is a pressing need for affordable, abundant, and sustainable sources of proteins to address the rising nutrient demands of a growing global population. The food and agriculture sectors produce significant quantities of waste and by-products during the growing, harvesting, storing, transporting, and processing of raw materials. These waste and by-products can sometimes be converted into valuable protein-rich ingredients with excellent functional and nutritional attributes, thereby contributing to a more circular economy. This review critically assesses the potential for agro-industrial wastes and by-products to contribute to global protein requirements. Initially, we discuss the origins and molecular characteristics of plant proteins derived from agro-industrial waste and by-products. We then discuss the techno-functional attributes, extraction methods, and modification techniques that are applied to these plant proteins. Finally, challenges linked to the safety, allergenicity, anti-nutritional factors, digestibility, and sensory attributes of plant proteins derived from these sources are highlighted. The utilization of agro-industrial by-products and wastes as an economical, abundant, and sustainable protein source could contribute towards achieving the Sustainable Development Agenda's 2030 goal of a "zero hunger world", as well as mitigating fluctuations in food availability and prices, which have detrimental impacts on global food security and nutrition.

Cereal bran proteins: recent advances in extraction, properties, and applications

The projected global population is expected to reach around 9.7 billion by 2050, indicating a greater demand for proteins in the human diet. Cereal bran proteins (CBPs) have been identified as high-quality proteins, with potential applications in both the food and pharmaceutical industries. In 2020, global cereal grain production was 2.1 billion metric tonnes, including wheat, rice, corn, millet, barley, and oats. Cereal bran, obtained through milling, made up 10-20% of total cereal grain production, varying by grain type and milling degree. In this article, the molecular composition and nutritional value of CBPs are summarized, and recent advances in their extraction and purification are discussed. The functional properties of CBPs are then reviewed, including their solubility, binding, emulsifying, foaming, gelling, and thermal properties. Finally, current challenges to the application of CBPs in foods are highlighted, such as the presence of antinutritional factors, low digestibility, and allergenicity, as well as potential strategies to improve the nutritional and functional properties by overcoming these challenges. CBPs exhibit nutritional and functional attributes that are similar to those of other widely used plant-based protein sources. Thus, CBPs have considerable potential for use as ingredients in food, pharmaceutical, and other products.

Extraction, bioactive function and application of wheat germ protein/peptides: A review

The aging population and high incidence of age-related diseases are major global societal issues. Consuming bioactive substances as part of our diet is increasingly recognized as essential for ensuring a healthy life for older adults. Wheat germ protein has a reasonable peptide structure and amino acid ratio but has not been fully utilized and exploited, resulting in wasted wheat germ resources. This review summarizes reformational extraction methods of wheat germ protein/peptides (WGPs), of which different methods can be selected to obtain various WGPs. Interestingly, except for some bioactive activities found earlier, WGPs display potential anti-aging activity, with possible mechanisms including antioxidant, immunomodulatory and intestinal flora regulation. However, there are missing in vitro and in vivo bioactivity assessments of WGPs. WGPs possess physicochemical properties of good foamability, emulsification and water retention and are used as raw materials or additives to improve food quality. Based on the above, further studies designing methods to isolate particular types of WGPs, determining their nutritional and bioactive mechanisms and verifying their activity in vivo in humans are crucial for using WGPs to improve human health.