The growing demand for sustainable protein sources has intensified interest in plant-based food systems. Pulses are well established and recognized as nutritious, sustainable protein sources (~15–30% dry weight), rich in lysine and limited in cysteine, methionine, and tryptophan amino acids. In contrast, Spirulina is characterized by a complete amino acid profile, high protein content (~50–70% dry weight), and bioactive potential. This comprehensive review explores the role of Spirulina as a complementary protein source in plant-based systems, with emphasis on its structural, technofunctional, and processing characteristics. A literature analysis was conducted to identify advances, trends, and gaps in their incorporation into food matrices. The findings indicate that, despite their nutritional and functional advantages, the application of microalgae and beans remains constrained by sensory and technological challenges, such as off-flavors and textural issues. The combination of microalgae with pulse-based ingredients represents a promising strategy to enhance amino acid balance, improve functionality, and develop nutritionally enriched products. Studies addressing multi-component systems remain scarce, especially in bakery and flour-based applications, as well as in understanding synergistic interactions between microalgae and pulse proteins in food matrices. This review highlights the potential of microalgae as key ingredients in next-generation food formulations. It identifies critical gaps that must be addressed to enable their broader application in food products.
The growing demand for sustainable, non-animal-derived, and low-allergenic protein alternatives has driven research into innovative sources such as microalgae. This review focuses on three key microalgal species Arthrospira platensis (Spirulina), Chlorella vulgaris, and Tetraselmis chuii. It examines their cell wall structures, protein content, and amino acid profiles. Protein extraction methods, including physical, enzymatic, and chemical approaches, are critically discussed. Downstream purification techniques aimed at improving protein purity and quality are also reviewed. Protein characterization methods are discussed, highlighting their relevance to food applications. The potential applications of microalgal biomass and protein extracts in food and beverage products are evaluated, with consideration given to their functionality, safety, and regulatory aspects. Despite significant advances in this field, further research is essential to optimize extraction and processing technologies, facilitate their integration into mainstream food production, and improve overall process efficiency.
E. Costa, M. Ribeiro, L. Filipe-Ribeiro et al.· Foods· 0 citations
The global population growth and the transformation of dietary structure are intensifying the contradiction between protein supply and demand, so there is an urgent need to develop sustainable alternative protein sources. Melon seeds, as a major by-product of the melon processing industry, are estimated to have an annual recyclable volume of approximately 738,000 tons. They are often discarded, causing resource waste and environmental pressure. Due to its well-balanced amino acid profile, melon seed proteins are regarded as a valuable source of nontraditional proteins. Building upon and extending previous foundational studies, this review systematically integrates current knowledge on melon seed proteins across multiple species, with emphasis on varietal differences, protein compositional, amino acid composition, and emerging extraction techniques. It also systematically introduces the functional characteristics of melon seed proteins and their wide applications in the conventional food matrices and emerging food systems. In addition, the key challenges limiting industrial translation and potential strategies, including lower technofunctional properties relative to conventional proteins, inherent antinutritional factors, and economic hurdles in large‑scale extraction and modification are also discussed. Melon seed proteins exhibit species-dependent nutritional advantages and favorable functional attributes, positioning them as promising complementary ingredients to conventional plant proteins. The development and utilization of melon seed proteins can effectively transform agricultural waste into health-promoting food ingredients.
Jincan Wu, Jingjing Xu, Zexu Li et al.· Comprehensive Reviews in Foo...· 0 citations
Protein hydrolysates (PHs) have emerged as a pivotal category of plant biostimulants in sustainable agriculture. They are derived from the enzymatic, chemical, or thermal hydrolysis of agro-industrial by-products of animal or plant origin. These complex mixtures of free amino acids, oligopeptides, and polypeptides enhance crop productivity, nutrient use efficiency, and abiotic stress resilience. This review examines and compares the production methods, chemical composition, agronomic performance, physiological mechanism, and safety profiles of animal-derived (A-PHs) and vegetal-derived (V-PHs) protein hydrolysates, with particular emphasis on hydrolyzed collagen (HC) as an emerging biostimulant. Furthermore, the specific physiological roles of proline in mediating plant stress tolerance and hydroxyproline-rich glycoproteins in maintaining cell wall integrity are evaluated. Animal-derived sources, including collagen, keratin, and fish by-products, are characterized by elevated glycine, proline, and hydroxyproline concentrations, amino acids with established roles in root architecture promotion, reactive oxygen species (ROS) scavenging, and osmotic adjustment under stress. Conversely, V-PH exhibit richer bioactive peptide profiles and superior environmental sustainability indices. Underlying mechanisms encompass hormone-like activities mimicking auxin and gibberellin signaling, transcriptional reprogramming of nitrogen assimilation pathways, antioxidant enzyme modulation, and rhizosphere microbiota stimulation.
This work explores the development of animal-free proteins produced in laboratory settings using innovative technologies such as precision fermentation, submerged fermentation, plant cell culture, and molecular engineering, which enable the production of high-quality proteins without relying on animal farming or large-scale traditional agriculture.
Tropical fruit processing generates substantial quantities of seed-derived by-products that remain underutilized despite their potential as sources of bioactive compounds, proteins, lipids, dietary fiber, and polysaccharides. This critical narrative review evaluates their conversion into functional ingredients by integrating compositional variability, pretreatment and extraction, antinutritional-factor mitigation, structural characterization, food-system performance, storage stability, gastrointestinal behavior, safety, regulatory readiness, and scale-up feasibility. Direct evidence was distinguished from mechanistic support derived from non-target botanical matrices. An exploratory semantic clustering of 100 PubMed records published in 2024–2026 was conducted with Carrot2 to organize application-oriented themes and identify knowledge gaps; its output was interpreted as a thematic aid rather than a quantitative trend analysis. The review also examines biochar production from exhausted or non-food-grade seed biomass as a complementary cascading route, considering feedstock properties, thermochemical conditions, physicochemical quality, safety, application performance, and techno-economic constraints. The main contribution is an evidence-derived multi-stage decision framework linking ingredient validation with residual-biomass valorization. Current evidence supports promising nutritional and technological applications but remains heterogeneous and predominantly laboratory-based, with limited standardized comparisons, in vivo validation, regulatory assessment, and pilot-scale studies. Advancing these materials therefore requires application-specific, safety-oriented, and economically realistic validation within circular bioeconomy systems.
C. Camacho-González, Lizeth Guardado-Valdivia, U. López-García et al.· Biomass· 0 citations
Plant based protein possesses significant potential in the food sector due to its economic, nutritional, and sustainability benefits. However, the presence of limiting factors in terms of digestibility, off flavors, and techno functionality reduces the appeal of plant proteins. Fermentation is a biological modification process to counteract these limiting factors, which modifies protein structure, functional properties (solubility, hydrophobicity, WHC/OHC, emulsion etc.), alters the amino acids, and forms flavor active metabolites. This review critically evaluates microbial interventions applied at different stages of plant protein isolation, highlighting their effects on protein functionality, flavor‐active metabolite formation, and gut health alongside a detailed discussion of microbial proteolytic pathways. The textural and flavor changes in protein products after fermentation are also discussed. Various plant sources, such as peas, legumes, millets, etc., along with different microbial strains (Lactic acid bacteria (LAB),
Bacillus, Aspergillus
, and
Saccharomyces
, etc.), physical conditions (time, temperature, pH) provide an impressive extent of microbial interaction during the fermentation process. Further systemic studies are required to understand the role of distinctive microorganisms and their biochemical pathways to determine the effect of different factors on the protein molecular level, leading to their quality and functional enhancements. Hence, fermentation can act as a fascinating biochemical process for the quality enhancements for the future development of modified, nutritious, and pleasant plant proteins to fulfill consumer requirements.
Disha, M. Madhumita, Dharmender Kumar et al.· Food Bioengineering· 0 citations