Alternative proteins support somatic and muscular development while remodeling the microbiome in zebrafish.

Soybean meal based diets have been suggested to cause gastrointestinal issues in certain species when used as a protein alternative. Using a randomized design, we tested 1,728 alligators in one of 13 communal pens offered one of two diets (seven pens (n = 928) of soybean-based protein diets and six pens (n = 800) of animal-based protein diets) to determine if soybeans would negatively affect the growth, hide quality, behavior and health, when compared with an otherwise identical diet using animal-based protein. Both feeds were nearly identical in composition for protein and fat percentages and identical for all minerals and elements. Crude protein was a minimum of 50%, crude fat a minimum of 12%, crude fiber a minimum of 4%, and phosphorous was maintained at 1%. From this information we estimated the One Welfare of using soy as a protein in commercial diets. Although there was a statistically significant decrease in belly width (p = 0.0009; harvested hide size) for alligators fed soybean-based protein diets, all other measured parameters of soybean vs. animal-based protein diets were comparable, suggesting this environmentally sustainable alternative protein source warrants consideration as a feed base. Weight was not significantly different suggesting either diet would yield similar volumes of meat. Total length was significantly affected by diet. Hide quality was not negatively impacted by protein type, with both diets producing high quality hides free of defects (assessed at the salted hide stage prior to tanning). Behaviors were not influenced by the feed type, with animals fed either diet using the pen structures the same. Further, feeding times were the same suggesting the soybean-based protein diet was equally easy to eat and palatable as the animal-based protein diet. Behavior and feeding suggested soy-based diets do not alter time budgets or activities. There were no differences in the frequency or severity of pathologies for animals fed either diet. Respiratory (lung and trachea as a proxy to measure dust inhalation), gastrointestinal (small intestine as a proxy to measure digestive disturbances), and renal (kidney as a proxy for excretory stress) histopathology demonstrated neither diet was causing overt problems. One Welfare conclusions were feeding a soybean-based protein diet did not cause production or welfare issues. Further, soybean protein-based diets may be an environmentally sustainable alternative to currently used animal-based diets. Research examining different soybean protein concentrations and sources is warranted.

Background and AimIn recent years, the importance of shifting from a largely animal-based protein diet to one rich in plant proteins have become increasingly apparent.  This is attributed to many factors of which most can be linked to aspects of food security, sustainability and climate change.  To that end, legume crops and specifically the so-called “neglected and underutilised species” are increasingly recognised as sources with the potential to address several of these factors important to the protein transition.  Bambara groundnut (Vigna subterranea (L.) Verdc.) [BGN] is one such a crop, which with a reported protein content of up to 27%, is increasingly recognised for its potential as an alternative plant protein source.  Research efforts have therefore been geared towards highlighting the functionality of BGN proteins, which although being of great value, are still lacking in terms of the link between the observed macroscopic functionality and the molecular and mesoscopic structural properties of the proteins; i.e. the structure-function relationship.  This is especially true for the gelation functionality of BGN proteins, which up till now have only been investigated for the minimum concentration above which a solid-like material can be observed after heating.  The aim of this thesis was therefore to gain insights into the structural properties of BGN proteins obtained from different processing streams and their resulting gelation properties.MethodsTo identify the interplay between processing, structure and functionality, BGN proteins of varying purity as obtained via different extraction routes were characterised for their physicochemical and structural properties, followed by characterisation of their gelation behaviour.  Hereto, techniques such as size-exclusion chromatography coupled to multi-angle laser light scattering provided detailed information on the molecular weight and size characteristics of the proteins, whilst microstructures were characterised with microscopic techniques (i.e. cryo-scanning electron microscopy and confocal laser scanning microscopy).  The gelling behaviour of the proteins were characterised in terms of their rheological responses and linked to scaling models, as a means of describing the resultant gel networks.  These techniques were also applied to evaluate the effect of pre-treatments (soaking and roasting) on the seed microstructures and composition of the resultant fractions, as well as to investigate the synergistic enhancement of BGN proteins in admixture with whey protein isolates.Results and ConclusionsVicilin proteins which are trimeric proteins (molecular weight around 150–170 kDa) were confirmed as the major storage proteins in BGN seeds with a high purity (>90% protein content); whilst also being present as the major component in the less pure BGN protein isolates.  The role of vicilin in the BGN protein isolates was evident in the gelation behaviour, where the rheological responses in terms of the elastic modulus G’ of the protein isolates, revealed a concentration dependence which closely resembled that of vicilin in the presence of 200 mM NaCl (conditions for highest solubility of BGN vicilin).  Furthermore, both BGN vicilin and BGN protein isolates were characterised as weak-link fractal structures, whilst microstructural images revealed inhomogeneous aggregates for both fractions.  These findings thus show that high purity BGN proteins (i.e. vicilin proteins) are not necessary to achieve the same functionality as the protein isolates with a lower purity.  Hence, the applicability of dry fractionation as a mild processing technique was also explored, which resulted in protein-enriched fractions with evident gel formation.  Branching out further on the processing aspect, it was observed that soaking as a pre-treatment method is beneficial to address the hard-to-cook properties associated with the seeds, whilst retaining a similar composition as that of the raw seeds.  Finally, BGN protein isolates also showed potential as partial animal protein replacers, based on the change in the rheological responses when combined with whey protein isolates.  Overall, the findings presented in this thesis provided new knowledge and thereby a better understanding of the structure-function behaviour of BGN proteins, which can be used to strengthen the position and steer the application of BGN as an alternative plant protein source.

Simple SummaryFish meal (FM) is the major protein source in aquafeed to achieve sustainable aquaculture production. However, the supply of FM is low due to high cost and low availability. There is ongoing conceited research to identify alternative viable protein sources to replace the finite FM. Novel camelina meal (CM) is a plant protein with high amino acids levels and has been tested as an alternative protein source in livestock feeding. However, there is limited information on supplementation of the CM in aquaculture diets. In this study, four diets were formulated to contain 0% plant protein, 205 g/kg soybean meal, and two levels of CM (205 g/kg and 330 g/kg) in diets fed to red seabream. Results indicated that adding CM 205 g/kg in diets-maintained growth performance, digestive enzyme activities, and nutrient digestibility regulated the immunity and stress resistance and modulated the growth-related genes in red seabream. These findings provide the first step in using novel CM and are essential for future practical formulations of feed for red seabream and other marine fish species.A 60-day experiment was designed to assess the effect of different ratios of fish meal (FM): camelina meal plant protein (CM) on growth response and relative gene expression of growth-promoting factors, feed utilization potency, digestive enzymes activities, apparent digestibility (ADC), stress response, non-specific immunity of Pagrus major. Four isonitrogenous (490.7 g/kg of crude protein) and isolipidic (91.5 g/kg total lipid) experimental diets were formulated and designated as camelina meal (CM0), soyabean meal (SBM20.5), CM20.5, and CM33 based on protein contents. At the end of the feed trial, significantly higher (p < 0.05) weight gain, specific growth rate, and feed intake but lower feed conversion ratio were recorded in fish fed CM0, SBM20.5, and CM20.5 than fish fed CM33. The lowest growth, feed utilization, enzyme activity, and digestibility were recorded in fish fed CM33. Significantly higher pepsin, amylase, and protease activities were observed in fish fed CM0, SBM20.5, and CM20.5 diets than fish fed CM33. The highest ADC of protein was recorded in fish fed CM0, SBM20.5, and CM20.5 diets. Hematocrit levels were depressed CM33 while total serum protein, total cholesterol, triglyceride, blood urea nitrogen, total bilirubin, aspartate aminotransferase, and alanine aminotransferase were not significantly changed by the inclusion of CM. Non-specific immune variables (lysozyme activity, peroxidase activity in serum and nitro blue tetrazolium) in fish fed CM0, SBM20.5, and CM20.5 were significantly higher than in fish fed CM33 diet. The superoxide dismutase of fish fed CM20.5 was not significantly different from CM0 and SBM20.5 (p > 0.05). Catalase and low salinity stress test show that CM0, SBM20.5, and CM20.5 were not significantly (p > 0.05) different, while CM33 was significantly lower than the rest of the diets. TBARs show that CM20.5 and CM33 diets were significantly different (p < 0.05), but CM20.5 was not significantly different from SBM20.5. Significantly higher hepatic IGF-1 and IGF-2 mRNA expression was found in fish-fed diet groups CM0, SBM20.5, and CM20.5 than fish fed CM33. The present study indicated that the addition of CM up 205 kg/kg to diet maintains growth, digestive enzymes, nutrient digestibility, immunity, stress resistance, and feed utilization efficiency of red sea bream.

Use of peanut meal as an alternative protein source in diets for Channel Catfish Ictalurus punctatus was evaluated in a 9‐week study under controlled laboratory conditions. Five practical diets (28% crude protein and 6% crude lipid) were formulated to contain 0, 10, 15, 20, and 25% peanut meal as a replacement for cottonseed meal and soybean meal in the control diet. The control diet was a plant‐based diet containing principally soybean meal (25%), cottonseed meal (20%), corn (20%), and corn germ meal (20%). All diets met or exceeded all known nutrient requirements of Channel Catfish. Twenty Channel Catfish fingerlings (mean initial weight: 12.8 g/fish) were stocked into 25 water flow‐through glass aquaria (110 L). The fish were fed once daily to apparent satiation. Among dietary treatments, there were no significant differences in feed consumption, weight gain, feed conversion ratio, and survival, and no differences in muscle protein, fat, or moisture levels. The results demonstrate up to 25% peanut meal can be used as a protein source alternative to cottonseed meal or soybean meal in Channel Catfish diets without adversely affecting growth, feed efficiency, and body composition.

The aging process is a multilayered biological phenomenon influenced by genetic, environmental, and lifestyle factors, with dietary protein intake playing a crucial role in maintaining cellular integrity and overall health. Among dietary choices, the impact of plant- vs. animal-based protein consumption on aging and telomere length has gained increasing scientific interest. Telomere length serves as a biomarker of cellular aging, and emerging evidence suggests that dietary composition may influence its maintenance. Plant-based diets, particularly those rich in legumes, whole grains, nuts, seeds, and vegetables, have been associated with longer telomeres and a reduced rate of biological aging. These effects are believed to stem from plant-derived nutrients’ anti-inflammatory and antioxidant properties. In contrast, excessive consumption of animal-based proteins, particularly red and processed meats, has been linked to telomere shortening, increased oxidative stress, and a higher prevalence of age-related diseases. Beyond aging, protein source selection is a critical factor in specialized medical settings, such as intensive care unit (ICU) nutrition therapy. Critically ill patients require adequate protein intake to support immune function, wound healing, and muscle preservation. While animal proteins have traditionally been preferred due to their high biological value and essential amino acid content, plant-based protein sources, when appropriately combined and supplemented, may serve as viable alternatives, reducing pro-inflammatory risks associated with critical illness. This review examines the comparative effects of plant- and animal-based protein diets on aging, telomere length, and ICU nutrition therapy, providing insights into optimizing dietary strategies for longevity and clinical recovery.

Alternative protein sources include: wheat protein, protein of lentils, chickpeas and other legumes, fish protein, chicken products, eggs, spray dried plasma and processed red blood cells, which serve many functions, including provision of essential and nonessential amino acids which enhance immune and are also highly palatable. Alternative protein sources include spray dried plasma, wheat protein, fish protein, Chicken products, eggs, and processed red blood cells serve many functions, including provision of essential and nonessential amino acids which enhance immune and are also highly palatable. Edible insects and marine organisms are promising alternatives. They have a large potential as a diet component due to their high nutritional value, complete protein content, fat, minerals and vitamins. The benefits from placing insect-based foods on the market are also reflected in positive environmental, economic and health issues. Currently, in most European countries the main problem limiting the usage of insects in human diet is the lack of acceptance of this type of food and its safety. Sensitizing people on the ecological liability of animal rearing and to escalate their interest in alternative proteins is important to create the change.

Comprehensive review of the digestibility of novel alternative protein sources: Current status and challenges.

The cost of compound feed is a constraint in intensive fish and poultry farming, contributing 60-80% of the total production costs, 70% of which is due to fish and soy meal used as protein source. This review presents the extent to which insects have been utilised as an alternative protein source in feed in sub-Saharan Africa (SSA). A key word search of agricultural, biological and multi-disciplinary databases and academic search engines was conducted for literature on the extent of research and utilisation of insects in poultry and fish feed in SSA. There is limited published information on the practice as well as technical and economic feasibility of the use of insects as alternative protein ingredients in compound feed. This is likely because research on the subject is fairly recently initiated and yet to be published. Excluding South Africa, rearing, processing and use of insects is still at experimentation level at laboratory scale. Insects (grasshoppers, house fly maggots, Westwood larvae, termites and garden snail) meal replaced conventional protein sources by 10-100% without affecting the growth performance of fish and poultry. In some cases, insect based feed performed better than conventional feed. Nutritional composition data of insects published for SSA majorly focused on proximate composition and not characterisation of the nutritional quality. Several research and development projects on the technical and economic feasibility, social acceptability and potential social-economic impact are ongoing and expected to increase available data when completed. Published research confirms the potential of insects for use in poultry and fish production systems and mass production and processing of target insects is the next necessary step. Based on available and ongoing research, piloting and up-scaling the use of insects as alternative protein sources in animal feed in partnership with private sector in SSA is necessary. This will confirm and enhance the technical and economic feasibility of using of insects as an alternative protein source on a commercial scale.

Traditional barbecue has relied heavily on animal-based proteins such as beef, pork, and poultry. However, the environmental impact and ethical concerns associated with conventional meat production have led researchers and food enthusiasts to explore alternative protein sources. This research review highlighted three main categories of alternative proteins: insects, plant-based options, and cultured meats. This mini-review would examine the feasibility of incorporating insect-based ingredients into barbecue recipes and evaluate their acceptability in terms of taste, texture, and consumer perception.

This opinion paper presents a short review of the potential impact of protein on muscle anabolism in cancer, which is associated with better patient outcomes. Protein source is a topic of interest for patients and clinicians, partly due to recent emphasis on the supposed non-beneficial effect of proteins; therefore, misconceptions involving animal-based (e.g., meat, fish, dairy) and plant-based (e.g., legumes) proteins in cancer are acknowledged and addressed. Although the optimal dietary amino acid composition to support muscle health in cancer is yet to be established, animal-based proteins have a composition that offers superior anabolic potential, compared to plant-derived proteins. Thus, animal-based foods should represent the majority (i.e., ≥65%) of protein intake during active cancer treatment. A diet rich in plant-derived proteins may support muscle anabolism in cancer, albeit requiring a larger quantity of protein to fulfill the optimal amino acid intake. We caution that translating dietary recommendations for cancer prevention to cancer treatment may be inadequate to support the pro-inflammatory and catabolic nature of the disease. We further caution against initiating an exclusively plant-based (i.e., vegan) diet upon a diagnosis of cancer, given the presence of elevated protein requirements and risk of inadequate protein intake to support muscle anabolism. Amino acid combination and the long-term sustainability of a dietary pattern void of animal-based foods requires careful and laborious management of protein intake for patients with cancer. Ultimately, a dietary amino acid composition that promotes muscle anabolism is optimally obtained through combination of animal- and plant-based protein sources.

Simple SummaryThis study aimed to evaluate diets with complete substitution of soybean meal (SBM) by an algae meal from Spirulina platensis (SM) or partly defatted larvae meal from Hermetia illucens (HM) as feed for piglets and growing pigs. Main feed ingredients of the experimental diets were wheat, barley, and SM or HM. The final diets contained 21% (piglets) and 13% (growing pigs) of SM or HM and nitrogen (N) balance studies were applied to measure parameters of apparent N digestibility, complex dietary protein quality, and individual amino acid (AA) efficiency according to the ‘Goettingen approach’. Diets were well accepted by the animals and an extended level of AA supplementation yielded improved dietary protein quality with both of the alternative feed proteins. However, HM based diets provided superior apparent N digestibility.Two age-dependent nitrogen (N) balance studies (average body mass 25 and 60 kg) utilized 16 male castrated piglets and 16 barrows to measure N utilization parameters of diets with complete substitution of SBM by alternative protein sources (SM, HM), but different AA fortifications. Lysine supplementation up to 80% of the recommended lysine (Lys) supply in diets HM (A) and SM (A) yielded similar protein quality data (63.6 ± 2.1 and 63.7 ± 3.4). Surprisingly, only in piglet diet HM (AA) did the extended AA supplementation (Lys, methionine (Met), threonine (Thr)) enhance protein quality (72.8 ± 6.7) significantly (p = 0.004). Similar trends were observed in growing pigs. However, when the level of histidine (His) in diet SM (AA) was increased, feed protein quality (71.8 ± 1.3) was significantly (p < 0.001) improved indicating the importance of adequate His supply in diets with a complete substitution of SBM by the algae meal (SM) under study. AA efficiency data extend the possibilities to explain the observed responses on protein quality. When an adequate AA balancing in the diet is guaranteed, from nutritional point of view both of the alternative proteins may replace SBM in pig diets.

Recently, there has been a growing interest in alternative protein sources. This study aimed to determine the textural and sensory properties of vegan burger patties produced with plant-based (soy and pea) protein sources instead of meat protein. For this purpose, 14 different vegan burger patties produced with soy and pea-based protein alternatives were obtained from different brands in the İstanbul market. Burger patties were analysed in terms of moisture content, cooking properties, instrumental colour, texture profile, and sensory properties. According to the results, pea-based burger patties have a higher moisture content and cooking loss and a lower cooking yield than soy-based patties. The L* and a* values of the pea-based patties tended to be higher than those of the soy-based patties, while the b* values were generally higher. In addition, the texture profile analysis of soy and pea-based burger patties shows differences in texture attributes that may affect consumer preference and overall eating experience. In the sensory evaluation, a significant difference between soy and pea-based burger patties was observed only for juiciness and spicy taste characteristics. The research findings shed light on alternative proteins' textural and sensorial properties and their role in the food industry, particularly in developing vegan burger patties. These differences in sensory attributes and colour and texture analysis between soy and pea-based burger patties highlight the importance of ingredient selection and formulation in developing plant-based protein products.

Decoding the meaning of alternative proteins: Connotations and music-matching

Are alternative proteins increasing food allergies? Trends, drivers and future perspectives

Comparative efficacy of amino acid availability and peptidomic analysis of alternative proteins from different sources under dynamic in vitro protein digestion