5 Innovative Alternative High Protein Sources Revealed
Discover the world of alternative high protein sources, offering nutritious and sustainable options for your diet. Dive into this exciting and healthy food journey.

In a world where sustainability and nutrition are paramount, exploring alternative high protein sources is more important than ever.
This article unveils five innovative options that are not only rich in protein but also echo the principles of environmental friendliness and dietary diversity.
From plant-based proteins and protein-rich legumes to the less conventional insect-based proteins and mycoproteins from fungi, each source offers unique nutritional benefits.
We also delve into the potential of aquatic plant proteins and microalgae, redefining what it means to consume protein responsibly.
These eco-friendly protein choices are not just about meeting dietary needs; they're about shaping a sustainable future for our planet.
Keywords: Alternative High Protein Sources, Sustainable Protein Options, Plant-Based Proteins, Insect-Based Protein, Protein-Rich Legumes

Main Findings
- The need for new, sustainable, and natural protein resources has arisen due to the increasing population and limited availability of high-quality protein sources, leading to the exploration of options such as insects, underutilized legume crops, weeds, and fungi.
- Insect proteins are a valuable source of nutrition due to their abundance of essential amino acids, essential fatty acids, and trace elements.
- Unconventional legume crops are highly nutritious and possess therapeutic properties, while also being able to grow well in extreme environmental conditions.
- The review explores alternative protein sources such as underutilized legume crops, aquatic weeds, fungi, and insects, including their production, incorporation in food products, and functional characteristics as novel foods.
- Safety is of paramount importance when considering the consumption of insects and underutilized legumes, as they may contain anti-nutritional factors and allergenic proteins.
- The review highlights the functional and biological activities of protein hydrolysates from various sources, including bioactive peptides with antihypertensive, antioxidant, antidiabetic, and antimicrobial properties.
Questions Answered
What are the nutritional benefits of insect proteins compared to traditional animal-based proteins?
Insects are a rich source of micronutrients and proteins, with an average protein content of 40% (ranging from 20% to over 70% depending on the species). They are particularly high in essential amino acids like threonine and lysine, which are important for human diets. Insect proteins are more digestible than plant proteins but less digestible than animal proteins. Additionally, insect proteins have excellent oil and water retention capacity, emulsion activity, and foaming activity, making them suitable for a wide range of food applications.
How does the cultivation of fungi on agro-industrial wastes affect the protein content?
Cultivating fungi on agro-industrial wastes can significantly increase their protein content. Edible fungi typically contain 19% to 45% protein, depending on various factors. However, when grown on agro-industrial wastes like corn stover or paddy straw, the protein content can exceed 45%. This makes fungal proteins a valuable source for fortifying and substituting animal-based proteins in food.
What are some of the bioactive properties of non-meat proteins and how are they released during food processing?
Non-meat proteins contain bioactive peptides (BAPs) with various health-promoting properties. BAPs can exhibit antioxidant, ACE inhibitory, antimicrobial, antiviral, and cytomodulatory activities. They are released from non-meat proteins during digestion, fermentation, germination, enzymatic hydrolysis, and food processing. The specific amino acid sequence of the peptide influences its biological activity.
Introduction
In recent years, the world has faced an increasing global population and the depletion of natural resources, with estimates projecting that we'll reach 9-10 billion people by 2050 A Trusted Source
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This surge in population has led to a growing demand for sustainable and nutritious food options.
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For a long time, plant-based proteins were considered nutritionally inferior to meat proteins, but this perception is changing A Trusted Source
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It's challenging to directly compare plant and meat proteins because plant proteins come with additional plant-based nutrients.
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Seitan, a pure gluten product, is popular in vegetarian and vegan diets and can be found in various forms like burgers, sausages, and nuggets.
Tofu, produced from soybean proteins coagulated with calcium ions, is a versatile dairy alternative.
However, gluten can be problematic for allergic individuals and those with celiac disease, and soy proteins can impart a bitter taste to food products, limiting their acceptability.
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Aquatic plants like duckweed, with their high protein content, are attracting attention as alternative protein sources for human nutrition.
Insects have long been a food source for over 2 billion people globally, with more than 2000 edible species known A Trusted Source
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The Promise of Uncommon Beans
Grass Pea: alternative high protein sources
Grass pea, a member of the Fabaceae family, has a global presence, cultivated across South and Southeast Asia, the Middle East, Eastern Europe, North America, South America, and East Africa A Trusted Source
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What sets grass pea apart is its protein content, ranging from 8.6% to 34.6%, surpassing the protein content of chickpeas, field peas, and French beans A Trusted Source
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Lupin: A Versatile Nutritional Dynamo
Lupin, a large genus comprising around 200 species, boasts four cultivated varieties: L. angustifolius (narrow-leafed), L. albus (white), L. luteus (yellow), and L. mutabilis (Andean).
Australia leads in lupin production, followed by Poland, Russia, Morocco, and Germany.
Lupin's nutritional profile is impressive.
It contains roughly 40% protein, lower fat content (~6%), and a host of essential amino acids.
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These compounds make lupin flour a valuable ingredient, especially in bakery products.
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Winged Bean: The Multipurpose Marvel
Winged bean (P. tetragonolobus), often found in humid countries like Sri Lanka and Malaysia, is a versatile legume.
It contributes to soil fertility by fixing atmospheric nitrogen, benefiting the growth of other crops like rice.
Although its large-scale cultivation is limited due to variability and low yields, its potential is undeniable.
From an agricultural standpoint, winged bean requires minimal external inputs, making it suitable for regions facing water scarcity and rising temperatures due to climate change.
Nutritionally, it rivals soybean in protein content while maintaining a balanced amino acid profile, including lysine, often lacking in cereal-based diets.
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Bambara Groundnut: A Protein-Rich Marvel
Bambara groundnut (V. subterrenea), an underutilized legume, boasts protein content comparable to soybean.
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They're rich in fiber, calcium, iron, and potassium, making them a valuable dietary choice, particularly the red-seeded varieties with higher iron content A Trusted Source
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Its starch and amylose content, along with dietary fiber, position bambara groundnut as a suitable choice for managing diabetes and high cholesterol.
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Mushrooms: More Than Just a Pizza Topping
In the pursuit of sustainable protein sources, edible fungi are emerging as nutritional powerhouses that warrant our attention.
These remarkable organisms, including popular species like Agaricus bisporus (button mushroom), Lentinula edodes (shiitake), Pleurotus spp., and Flammulina velutipes, offer a promising solution to our growing demand for sustainable proteins A Trusted Source
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Edible Fungi: A Protein-Rich Option
Edible fungi vary widely in their protein content, ranging from 19% to 45% of dry matter.
This variability depends on factors such as the species, maturity stage, fungal parts used, substrate, and cultivation techniques employed A Trusted Source
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Mycoprotein: The Fungal Protein Marvel
One standout product in the world of fungal proteins is mycoprotein, derived from Fusarium venenatum.
It has received approval from the UK Government for sale since the 1990s and is globally exported under the brand name Quorn™ A Trusted Source
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Mycoprotein is a dried fungal powder renowned for its high nutritional value and is frequently used to fortify various foods.
As a substitute for animal-based proteins, mycoprotein has gained traction for its nutritional benefits and safety.
Extensive toxicology studies have confirmed its safety for human and animal consumption A Trusted Source
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Amino Acid Richness and Nutritional Value
Edible fungi, particularly Pleurotus spp., boast an impressive amino acid profile, including all essential amino acids, with leucine, aspartic acid, phenylalanine, and lysine as the most abundant.
Umami amino acids, along with non-essential ones like gamma-aminobutyric acid (GABA) and ornithine, are also present A Trusted Source
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A study on human volunteers demonstrated that mycoprotein's biological value matches that of milk proteins A Trusted Source
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The protein-to-energy ratio (PER) for various edible mushrooms, ranging from 16% to 37% protein content, is comparable to foods like beef jerky, whole milk, and lentils A Trusted Source
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Consuming 100 grams of dried mushrooms can cover a significant portion of the Recommended Dietary Allowance (RDA) for both men and women A Trusted Source
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Nutritional and Health Benefits
Beyond their nutritional value, proteins derived from edible fungi exhibit remarkable biological activities that can enhance health and prevent diseases.
These activities include lectins, fungal immunomodulatory proteins (FIP), ribosome-inactivating proteins (RIP), antimicrobial or antifungal proteins, ribonucleases, laccases, and bioactive peptides A Trusted Source
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Versatile Applications and Advancements
Mycoproteins find their way into a wide range of food products, including baked goods, meat products, and dairy items A Trusted Source
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They not only enhance nutritional profiles but also improve physicochemical and organoleptic characteristics.
For instance, the addition of recombinant Ery4 laccase from P. eryngii to a dairy product not only increased its antioxidant properties and texture but also raised protein content, resulting in a 10% higher product yield compared to control samples A Trusted Source
Loi, M.; Quintieri, L.; Fanelli, F.; Caputo, L.; Mulè, G. Application of a recombinant laccase-chlorogenic acid system in protein crosslink and antioxidant properties of the curd. Food Res. Int. 2018, 106, 763–770. [Google Scholar, CrossRef] A Trusted Source
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This protein also exhibited the potential to degrade mycotoxins, elevating food safety standards A Trusted Source
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Green Protein
Plant Proteins: Abundance in Leaves
Leaves, often overlooked, are a promising reservoir of plant proteins, with over 70% of their protein content residing in the chloroplast.
Here, the dominant protein is ribulose bisphosphate carboxylase (RuBisCO), an enzyme crucial for photosynthesis A Trusted Source
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Among these green gems, Moringa oleifera, the drumstick tree, and Wolffia arrhiza and Wolffia globosa, commonly known as duckweed, stand out as fully edible plants boasting high protein content.
While leaves hold the promise of plant proteins, they come with challenges.
Nutrient bio-accessibility in vegetable foods, particularly proteins, is hindered by compounds like cellulose, hemicellulose, polyphenols, and anti-nutritional factors such as protease and α-amylase inhibitors.
These substances interfere with both food proteins and digestive enzymes A Trusted Source
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However, when applied to leaf powder, traditional methods like two-step alkaline extraction and isoelectric precipitation face hurdles due to the low solubility of membrane proteins compared to seed storage proteins.
Moringa oleifera: A Nutritional Powerhouse
Moringa oleifera, a perennial plant thriving in tropical and subtropical regions, offers a multifaceted nutritional profile.
It encompasses various edible parts, including leaves, roots, seeds, bark, fruit, flowers, and immature pods, with leaves being particularly rich in proteins, vitamins, and minerals.
These leaves play a vital role in the diets of pregnant women and weaning children, with scientifically proven health benefits A Trusted Source
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Efforts to extract proteins from Moringa leaf powder using cellulolytic enzymes have led to the creation of high protein concentrates (55.7%, w/w), surpassing what can be achieved with alkaline extraction alone A Trusted Source
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This concentration process substantially enhances in vitro digestibility, with a digestibility score of 99.9% and PDCASS 91.42%, comparable to whey proteins and aligned with FAO requirements A Trusted Source
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Another avenue to improve leaf digestibility is fermentation, as demonstrated by solid-state fermentation of drumstick leaf flour using microorganisms like Aspergillus niger, Candida utilis, and Bacillus subtilis.
This process yields high-quality proteins, increased concentrations of small peptides and amino acids, and reduced levels of anti-nutritional factors A Trusted Source
Shi, H.; Yang, E.; Li, Y.; Chen, X.; Zhang, J. Effect of solid-state fermentation on nutritional quality of leaf flour of the drumstick tree (Moringa oleifera Lam.). Front. Bioeng. Biotechnol. 2021, 9, 626628. [Google Scholar, CrossRef].
Moringa's potential as a valuable ingredient extends to a range of food products, including baked goods, meat products, and more.
However, the exploration of Moringa's bioaccessibility and bioavailability in meat product formulations remains an evolving research area A Trusted Source
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Duckweed: The Aquatic Protein Gem
While Moringa thrives on land, duckweed takes center stage in aquatic ecosystems.
This monocotyledonous plant, found in various genera, boasts an impressive protein content of up to 43% on a dry basis, featuring all essential amino acids A Trusted Source
de Beukelaar, M.F.A.; Zeinstra, G.G.; Mes, J.J.; Fischer, A.R.H. Duckweed as human food. The influence of meal context and information on duckweed acceptability of dutch consumers. Food Qual. Prefer. 2019, 71, 76–86. [Google Scholar, CrossRef].
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Protein isolates from duckweed have shown promise, with preparations reaching 67.2% protein concentration (w/w).
These isolates exhibit good solubility at pH levels above 6 and gel strength comparable to soy proteins, although slightly lower than egg white proteins at pH 4 to 7 A Trusted Source
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Microalgae: Underwater Protein Marvels
Microalgae, aquatic plants residing beneath the surface, have emerged as protein-rich food ingredients, boasting protein content ranging from 40% to 70%, depending on the species.
They also offer polyunsaturated fatty acids, minerals, and vitamins A Trusted Source
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Notably, microalgae synthesize RuBisCO, albeit in lower quantities compared to terrestrial and shallow aquatic plants like duckweed A Trusted Source
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Their essential amino acid profiles align with those of soybean and egg proteins A Trusted Source
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Two microalgae species, Chlorella vulgaris and Arthrospira platensis (Spirulina), have taken the spotlight as potential novel food ingredients.
Chlorella sp. falls outside the scope of EU novel food regulations, while Spirulina sp. requires dedicated safety and nutritional assessments A Trusted Source
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One challenge associated with whole microalgae biomass is its distinct "grassy-fishy" flavor and color.
Efforts have led to the development of chlorophyll-free strains and chemically induced random mutagenesis, yielding honey/yellow and white Chlorella powders with high protein content (40–50%) and essential fatty acids A Trusted Source
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However, the presence of cellular walls, constituting 10% of dry weight, hampers protein digestibility.
Digestibility rates vary by species, with A. platensis boasting higher rates (up to 78%) due to its peptidoglycan-rich cell wall A Trusted Source
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Microalgae protein extracts are employed to complement formulations for meat analogues, offering excellent emulsifying and foaming properties.
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Bugs as Bites
Insects are emerging as an unexpected yet highly nutritious solution to the quest for alternative high protein sources.
With an average protein content of 40%, ranging from 20% to over 70% depending on the species, insects offer a promising option A Trusted Source
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Surprisingly, these six-legged critters are already a common food source for 2 billion people in 119 countries worldwide.
While over 2000 insect species are edible, the most popular choices for protein include Coleoptera Beetles, Lepidoptera Caterpillars, Hemynoptera (wasps, bees), and ants.
While insects have long been a staple in the diets of Asian populations, particularly in India, China, Thailand, South Korea, Japan, Mexico, Brazil, and various parts of Africa, they remain novel foods in Western countries A Trusted Source
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However, the landscape is changing rapidly.
The need for sustainable protein sources, coupled with the enticing advantages of insect farming, is transforming Western eating habits and European markets.
In Europe, three insect species, namely Tenebrio molitor, Gryllodes sigillatus, and Schisocerca gregaria, stand out as potential food sources due to their high protein content, estimated at 52%, 70%, and 76%, respectively A Trusted Source
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Insects boast high threonine and lysine levels, though they may have lower methionine or tryptophan content.
Nevertheless, their essential amino acid profile ranges from 46% to 96%, surpassing the lowest recommended levels for human diets (>40%).
Insects often outshine plants and animals in terms of amino acid quantity A Trusted Source
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Additionally, insect proteins excel in oil and water retention, emulsion activity, and foaming activity.
Notably, edible grasshoppers (S. gregaria) and honeybees (Apis mellifera) have remarkable emulsifying properties akin to whey protein, positioning them as alternative emulsifiers A Trusted Source
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Nevertheless, the functional characteristics of insect proteins can vary greatly depending on the species.
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In recent years, several European directives and regulations have been established to regulate the production and commercialization of these novel foods.
One notable development is the authorization of insect-processed animal proteins in formulated pig and poultry feeds A Trusted Source
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The International Platform of Insects for Food and Feed (IPIFF), which represents stakeholders involved in insect production for food and feed, actively encourages European member states to adopt these regulations, supported by a favorable opinion from the EFSA Panel on Nutrition, Novel Foods, and Food Allergens (NDA) A Trusted Source
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It's essential to highlight that in the case of house cricket, EFSA has noted potential allergenicity concerns, emphasizing the importance of safety assessments A Trusted Source
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In response to modern sedentary lifestyles and the demand for healthier diets, innovative functional products are emerging.
Bread, a dietary staple worldwide, is ripe for enhancement due to its protein deficiency in essential amino acids like lysine and threonine A Trusted Source
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Fortification of wheat bread with various edible insect flours, including mealworm, buffalo worm, cricket, and larvae of the black soldier fly, has improved the bread's biological value due to their high protein content A Trusted Source
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Cricket powder has been employed to increase protein content in muffins, and gluten-free bread enriched with cricket powder has shown promise, with high nutritional value proteins and improved texture A Trusted Source
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The applications of edible insects are expanding, with over 160 patents and numerous articles exploring their use in various food products A Trusted Source
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Beyond Nutrition
Biologically active peptides (BAPs) are an exciting frontier in the quest for alternative high protein sources, offering numerous health benefits.
These peptides, with a molecular weight below 6 kDa and containing 3 to 20 amino acid residues, remain inactive within the parent protein until they are released and transported to their active sites A Trusted Source
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The structure and activity of BAPs are closely linked, with their amino acid sequences playing a crucial role.
Amino acids like alanine, cysteine, histidine, lysine, leucine, methionine, proline, valine, tryptophan, and tyrosine contribute to their antioxidant properties A Trusted Source
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Additionally, Pro, Lys, or aromatic amino acids contribute to their ability to inhibit Angiotensin Converting Enzyme (ACE) A Trusted Source
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BAPs can be released from food proteins through various processes, including gastrointestinal digestion, fermentation, germination, enzymatic hydrolysis, and food processing.
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The versatility of BAPs extends to a wide range of activities, impacting various bodily systems.
In the gastrointestinal system, they can act as anti-obesity and satiety peptides.
In the cardiovascular system, they may have positive effects, while in the immune system, they exhibit antimicrobial, antibiofilm, antiviral, and cytomodulatory properties A Trusted Source
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Some BAPs even influence the nervous system, acting as opioid peptides.
Although many BAPs have been derived from animal proteins, alternative sources are being explored to discover novel sequences.
However, identifying these bioactive sequences remains a challenge due to the lack of a tailored pipeline for isolation and mass spectrometry mapping.
In contrast, protein hydrolysates are often mapped through mass spectrometry, with bioactivity predictions made via bioinformatics without in vitro validation.
Table 3 provides a list of active peptides from alternative sources, although it's worth noting that these sequences represent the only identified ones so far, mainly due to studies focusing on protein hydrolysates and their partially purified fractions.
Proteins and peptides derived from major legume species, such as soybean, cowpea, groundnut, common beans, pea, and chickpea, exhibit a wide spectrum of biological activities, ranging from nutraceutical to therapeutic potential.
These peptides can be produced through in vitro hydrolysis using food-grade enzymes like alcalase or through various processes such as fruit ripening, fermentation (for products like soy sauce, tempe, and natto), and germination (for sprout production) A Trusted Source
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Minor legume proteins, except lupin, remain uncharted territory for peptide exploration.
Lupin-derived peptides, for instance, display opioid and immune-modulating effects, as well as potential antidiabetic properties A Trusted Source
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Enzymatic hydrolysis with papain has proven highly efficient in producing ACE-inhibitory and antioxidant-rich winged bean seed hydrolysates.
These peptides have demonstrated their effectiveness in reducing blood pressure in rat models, underscoring their potential as functional food ingredients A Trusted Source
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Similar beneficial effects have been observed with Bambara groundnut protein hydrolysates and their peptide fractions A Trusted Source
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While grass pea-derived peptides remain relatively unexplored, their potential bioactivity is of interest.
Proteins and peptides with biological activity from edible fungi are gaining attention, with various reported benefits A Trusted Source
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Efficient and sustainable production of these proteins and peptides represents a current challenge.
Moringa oleifera seed or leaves protein hydrolysates have displayed antioxidant, anti-inflammatory, hypoglycemic, antimicrobial, antihypertensive, and hyperuricemia-regulating properties, opening up opportunities for functional food development A Trusted Source
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Microalgae are another intriguing source of bioactive peptides.
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Techniques such as enzymatic digestion followed by membrane filtration and chromatographic purification are commonly used to generate these peptides A Trusted Source
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Insect proteins, like silkworm pupa, have been associated with a reduced risk of various diseases, including cardiovascular diseases and cancer A Trusted Source
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Silkworm pupa hydrolysates have shown bioactive properties such as ACE inhibition, antioxidant activity, immunomodulation, and potential to alleviate hypercholesterolemia A Trusted Source
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These hydrolysates may also possess antitumor activity, although further research is needed to confirm these findings.
Techniques like ultrasound have been employed to assist enzymatic hydrolysis and enhance the production of bioactive compounds A Trusted Source
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Similar bioactive peptide sequences have been identified in other insects such as cricket (Gryllodes sigillatus), mealworm (T. molitor), and locust (Schistocerca gregaria) A Trusted Source
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Safety First
Minor Legumes and Their Neurotoxic Compounds
While minor legume crops offer excellent nutritional value, some pose potential health risks due to inherent toxicity.
Take grass pea, for example, which contains a neurotoxic non-protein amino acid called β-N-oxalyl-L-a, b-diaminopropionic acid (β-ODAP) in its seeds.
Overconsumption of these seeds, as a staple in an unbalanced diet for 3–4 months, can lead to neurolathyrism.
Symptoms include leg muscle paralysis, muscular rigidity, and weakness in both humans and domestic animals.
The β-ODAP content varies widely in grass pea seeds, ranging from 0.02% to 2.59%, influenced by environmental factors and cultivated varieties A Trusted Source
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Efforts have been made to develop grass pea varieties with low β-ODAP content.
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Lupine, another legume, can cause severe intoxications when consumed excessively.
This safety issue primarily arises from the high content of quinolizidine alkaloids in bitter lupine species, ranging from 1% to 3% of the dry weight of their seeds.
Lupanine, a quinolizidine alkaloid, is the major component, and its high content has been associated with severe intoxication A Trusted Source
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Cross-reactivity with peanut and other legumes has been recorded, leading to its inclusion among priority allergens in European legislation A Trusted Source
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Challenges with Winged Bean and Bambara Groundnut
Winged bean and Bambara groundnut are rich in anti-nutritional factors (ANFs) that can limit their consumption.
Tannins, lectins, flatulence factors, phytoglutenins, saponins, and cyanogenic glycosides in winged bean, as well as phytates and tannins in Bambara groundnut, reduce the bioavailability of nutrients and minerals by forming complexes during digestion.
These substances can also inhibit enzyme activity and affect food protein quality A Trusted Source
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Safety Concerns with Mycoproteins and Microalgae
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Safety of Insect-Based Proteins
Using insects as food ingredients introduces biological, chemical, and allergenic risks.
Hot slaughtering and cooking can help mitigate microbiological risks, while chemical contamination concerns focus on heavy metals and environmental pollutants like hormones and pesticides A Trusted Source
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Looking Ahead
The search for alternative protein sources beyond meat has surged, driven by health benefits and sustainability.
Algae, insects, fungi, and underutilized crops offer eco-friendly options.
Legumes like grass pea, lupine, winged bean, and Bambara groundnut shine for their hardiness and rich seeds.
Edible mushrooms are protein-packed with vitamins and low in fat.
Aquatic plants and microalgae are nutrient-rich ingredients on the rise.
Insects, with over 2000 edible species, lead in protein and micronutrients.
As plant-based protein demand grows, driven by health and bioactive compounds, vegetarian and vegan diets are on the rise.
Safety concerns call for protein quality reevaluation as dietary trends shift toward novel proteins.
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