It is suggested that Tenebrio molitor larvae (yellow mealworms) have the capacity to fix non-protein nitrogen (NPN) to produce amino acids. To test this, mealworms were fed an alpha-cellulose-based synthetic feed (Cell+) containing sources of energy (lipid and glucose), minerals and multivitamins, at concentrations predicted to be like wheat bran (WB), the same feed with casein added (13.8 g/100 g) (casein+), or WB. Following 24 days on the Cell+ diet mealworms did not grow nor pupate, whilst on the Casein+ these were significantly greater, but did not quite reach the values for WB. When casein was replaced (equivalent nitrogen content) with various dietary NPN sources, including urea (Urea+), potassium nitrate (V) (Nitrate+) or ammonium bicarbonate (Amm+), growth and pupation was the same as Cell+, with the death rate being lower than Casein+ or WB. Mealworms fed Urea+ or Amm+ had no difference in crude protein composition (per unit DM) compared to WB, whilst Nitrate+ fed mealworms were significantly lower than all non-WB diets. Apart from phenylalanine, there were no changes in indispensable amino acid composition, but there were significant changes in several dispensable amino acids. The crude fat content of mealworms fed NPN was significantly lower than those fed Casein+ or WB. Of the major fatty acids making up crude fat (palmitic (>11%), oleic (>25%) and linoleic (>24%)), only oleic acid was different, with diets containing protein having the highest concentration. In conclusion, this study demonstrates that mealworms are unable to utilise NPN as the sole nitrogen source for either growth or pupation.

An understanding of the impact of dietary nutritional composition on growth, development and composition of Tenebrio molitor larvae (mealworms) could help optimise production systems. Replicate containers of mealworms fed for 24 days on synthetic cellulose-based feeds containing different combinations of protein (casein, Cas), lipid (wheat germ oil, WGO), carbohydrate (glucose) and a mineral/vitamin premix (MV) were compared to a control diet of wheat bran (WB). Mealworms fed only cellulose (C) ceased to grow after 10 days, and did not pupate. Addition of casein alone did not restore growth but did induce pupation (much slower than in WB-fed worms). Mealworms fed C+Cas-based diets showed a marked increase in the relative proportion of body protein to fat, compared to those fed wheat bran. The addition of MV to the C+Cas diet restored growth and pupation, though not to the same level as WB. MV-fed worms maintained a significantly increased protein/fat composition. The further inclusion of WGO or WGO + glucose further increased growth, whilst WGO + glucose reduced pupation. Overall, the highest yield of protein (per container) was seen in the C+Cas+MV+WGO-fed mealworms, which was 50% higher than in the WB group (largely due to the decreased pupation rate). Furthermore, the lipid yield was 50% lower than in WB-fed mealworms. By contrast, the addition of glucose to this diet maintained a high protein yield but increased the lipid yield to similar levels as seen in WB-fed mealworms, with an associated significant increase in the relative proportion of the polyunsaturated fatty acids (PUFA), linoleic and a-linolenic acids. The results indicate that sources of protein, lipid, minerals and multivitamins are all required to maximize protein whilst decreasing lipid deposition in mealworms. However, the addition of glucose (and presumably other digestible carbohydrates) increased lipid deposition and specifically the PUFA content.

Human dietary patterns are a major cause of environmental transformation, with agriculture occupying ~ 50% of global land space, while food production itself is responsible for ~ 30% of all greenhouse gas emissions and 70% of freshwater use. Furthermore, the global population is also growing, such that by 2050, it is estimated to exceed ~ 9 billion. While most of this expansion in population is expected to occur in developing countries, in high-income countries there are also predicted changes in demographics, with major increases in the number of older people. There is a growing consensus that older people have a greater requirement for protein. With a larger and older population, global needs for protein are set to increase. This paper summarises the conclusions from a Rank Prize funded colloquium evaluating novel strategies to meet this increasing global protein need.

Maximising the yield of product from livestock is common practice in the agriculture industry and there is potential to extend this practice to the emerging insect industry, to produce high-quality, sustainable protein. Tenebrio molitor larvae, commonly called yellow mealworms, were fed for 28 days on wheat bran containing the juvenile hormone analogue, pyriproxifen at either 2 mg pyriproxifen/kg wheat bran (JH-PL) or 15 mg pyriproxifen/kg wheat bran (JH-PH). As expected, pupation was inhibited in both pyriproxifen treated groups and significant changes in nutritional composition were observed. Pyriproxifen treated mealworms had a higher protein content per 100 grams of dried material, while fat content was reduced 68% in JH-PH compared to control. These changes were associated with an increase in moisture content and reduction in energy content. The fatty acid profile of extracted fat also displayed significant alterations, with pyriproxifen treated mealworms showing an increase in proportions of saturated fatty acids, reduction in oleic acid but no effect on linoleic acid. The amino acid composition also exhibited a change in composition as a result of pyriproxifen treatment, including an increase in the essential amino acid, lysine, in JH-PH treated mealworms. This change in amino acid profile was associated with a change in the protein composition as observed on SDS-PAGE, with the appearance of a new band identified as the egg-yolk protein, vitellogenin, which has lipid-transporter activity. Hence, pyriproxifen treatment of mealworms has a repartitioning effect, resulting in an increase in the proportion of protein and a decrease in fat on a dry matter basis, demonstrating that mealworm nutrient composition can be manipulated to provide a higher value feed ingredient.

The adoption of plant-based meat analogues is increasing as an alternative to real meat products among consumers because they offer a more ecologically friendly and sustainable source of protein while also alleviating the ethical concerns related to livestock rearing and slaughter (1). However, there are concerns regarding plant-based meat analogues in terms of its nutritional quality, particularly their protein digestibility. This study aims to compared between chicken and plant-based chicken analogues in terms of nutritional composition and degree of protein hydrolysis. Proximate analyses were performed for raw and cooked samples to assess protein, fat, and energy concentrations in two chicken samples (breast and thigh) and four commercial plant-based chicken (P-C1[Wheat Protein 37%, Pea Protein 10%], P-C2 [ Soya Protein 63%], P-C3 [ Soya and Wheat Protein 83%], and P-C4 [Soya Protein 30%, Pea Protein 2%]). As a first step, the proximate analyses were assessed for the averaged samples, then the product-cooking interactions was assessed using a one-way ANOVA followed by Tukey test (p <0.05). In vitro digestion was performed following the INFOGEST harmonised static in vitro digestion model (2) for cooked samples. After digestion, o- Phthaldialdehyde (OPA) assay was carried out to measure the degree of protein hydrolysis for each sample, and two-way ANOVA test was performed. Protein content of chicken was higher compared with the plant-based chicken, whereas fat content and energy concentrations were higher in plant-based chicken. The protein content of chicken was higher for raw and cooked samples (raw: 19.8 ± 0.38 g/100 g; cooked: 30.55 ± 4 g/100g), compared with plant-based chicken (raw: 13.8 ± 5.3 g/100 g; cooked: 23.4 ± 4.5 g/100g). Plant-based chicken have a higher fat content and energy concentrations for raw and cooked samples (raw:6.52 ± 1.5 g/100 g; cooked: 9.6 ± 3.17 g/100g) and (raw:189.4 ± 28.1 g/100 g; cooked: 291.3 ± 48.1 g/100g) respectively; compared to chicken fat content (raw:4.6 ± 2.7 g/100 g; cooked: 6.1 ± 4 g/100g) and energy concentration (raw:150.9 ± 25.4 g/100 g; cooked: 228.3 ± 20.7 g/100g). The product-cooking interactions showed a significant increase (P ≤0.0001) in the protein content (raw: 15.6 ± 2.3g/100g to 19.8 ± 0.74 g/100g; cooked: 21.4 ± 0.55 g/100g to 33.06 ± 0.71 g/100g), and fat content P<0.001 (raw: 2.7 ± 0.06 g/100g to 8.3 ± 0.27 g/100g; cooked: 3.29 ± 0.19 g/100g to 13.22 ± 0.33 g/100g) in both chicken and plant-based chicken samples. No significant product-cooking interactions on energy content was found. The results from a two-way ANOVA test of the OPA and the degree of hydrolysis analyses demonstrated a significant increase in the degree of hydrolysis of chicken samples compared with plant-based chicken (P<0.0001). The degree of hydrolysis and digestibility of chicken and chicken analogues was influenced by protein type, nutrient composition, and processing. These findings would provide substantial information for the improvement of plant-based chicken products with enhanced nutritional profiles. This work will be extended to investigate the availability and digestibility of individual amino acids.

Insects are of high interest as a sustainable source of nutrients to be included in the food production system. The larvae of Tenebrio molitor, commonly known as yellow mealworms (MW), have a high protein content, which means potential applications in the animal feed and human food sectors. However, previous reports have shown considerable variability in the nutrient composition of mealworms, which may in part, be due to harvesting at different developmental stages. A better understanding of the regulation of composition during development would potentially facilitate future attempts to manipulate nutrient content, perhaps through gene editing, to maximize commercial value. In the present study, mealworms were harvested at various time points within a 24 day period leading up to the start of pupation. At the earliest time points (between days -24 and -17), a 44% increase in fat content was seen, which was maintained throughout the rest of development. By day -12, protein content fell by 12%, a change that was also maintained. Throughout development there was a change in fatty acid composition, with a shift from oleic acid being the major fatty acid at day -24, to linoleic acid being predominant at later time points. In an attempt to better understand the genetic basis of these changes, an analysis of the transcriptome was undertaken. In the absence of a specific annotated genome for the mealworm, an Affymetrix GeneChip microarray for Drosophila was utilized. The hybridisation of RNA extracted from five developmental stages (larvae and pupae) showed differential gene expression; and some potential orthologs were identified which may be involved in regulating nutrient composition during development. However, we were unable to identify a significant proportion of the most highly regulated genes, highlighting the need for a fully annotated mealworm genome.

There is an urgent need to alleviate protein deficiencies in low-income countries where cerealbased diets dominate. The objective of this study was to use the INFOGEST static digestion method and a recently established analytical workflow to determine the in vitro amino acid digestibility and protein quality of seven maize varieties grown in Malawi. Protein quality was measured using the in vitro digestible indispensable amino acid score (DIAAS). Amino acid digestibility was higher for the dehulled, low fibre, provitamin A maize flour (66%), compared to whole grain maize flours (51-61%), suggesting that the presence of fibre reduced digestibility (p < 0.05). Lysine was the limiting amino acid in all varieties, with the following DIAAS values for each variety; Provitamin A maize - 24, SC 719 - 32, Mtsikinya - 37, SC 167 - 39, Quality protein maize (QPM) - 40, Bantum - 40, SC 403 - 44. In addition to the variety of maize, protein quality was dependent on the level of processing and the agronomic practice applied with higher protein quality for the SC 403 variety in which zinc enriched fertilizer was applied. Comparing protein quality data with published in vivo data showed that DIAAS data were in closer agreement than amino acid digestibility data, which was slightly lower than published values, with mean in vitro amino acid digestibilities of 56-70% compared to a mean in vivo value of 77%. Overall, the in vitro method was able to correctly predict both the direction and magnitude of response. The INFOGEST digestion method coupled with the new analytical workflow will therefore be useful in the screening of high protein cereal crops and subsequent development of cereal-based foods with high protein quality.

This chapter explores protein metabolism and its requirements. Proteins are the most diverse of the large macromolecules which provide structure and enable the function of the organism. The protein quality of human diets is predicted by protein or amino acid digestibility and the amino acid score, which is calculated in comparison with an age-related reference amino acid pattern. Many plant-source proteins have amino acid scores comparable to animal-source proteins, and this is because plant foods are chemically diverse. The chapter then explains that global national protein consumption patterns reflect the intake of animal source foods (ASFs) before mentioning the challenge of meeting protein needs with expanding populations in developing countries.

Bambara groundnut (BG) offers great potential for sustainable food and nutritional security in the face of a growing population and changing climate. However, its utilization remains restricted by the hard-to-cook phenomenon of seed and the presence of anti-nutritional factors (ANFs). Fermentation has been reported to enhance the nutritional value and reduce ANFs in leguminous seeds. The induced fermentation technology exhibits greater control over the process parameters and ensures the fermented product's quality, reproducibility, and safe consumption. Hence, this review highlights the importance of fermentation technology in overcoming the challenges of processing hard-to-cook BG while retaining its nutrients and flavor. This paper also reviews the food safety measure and risks of consuming fermented BG Future research on the fermented BG's nutrient digestibility should be of concern to unlock its full potential as human food or animal feed.

We estimated dietary supplies of total and available protein and indispensable amino acids (IAAs) and predicted the risk of deficiency in Malawi using Household Consumption and Expenditure Survey data. More than half of dietary protein was derived from cereal crops, while animal products provided only 11%. The supply of IAAs followed similar patterns to that of total proteins. In general, median protein and IAA supplies were reduced by approximately 17% after accounting for digestibility, with higher losses evident among the poorest households. At population level, 20% of households were at risk of protein deficiency due to inadequate available protein supplies. Of concern was lysine supply, which was inadequate for 33% of households at the population level and for the majority of the poorest households. The adoption of quality protein maize (QPM) has the potential to reduce the risk of protein and lysine deficiency in the most vulnerable households by up to 12% and 21%, respectively.

Total and per capita protein consumption rates in US diets, whether from plant or animal sources, rank among the highest in the world. When protein consumption outpaces physiologic protein demands, excess amino acids are degraded in the human body and nitrogen (N) is excreted and released to the environment, mainly in the form of urea. Such excess reactive N can enter downstream environments, thereby impairing human and ecosystem health as well as contributing to economic losses. We show that matching protein consumption with physiologic requirements would reduce US hydrologic N losses to aquatic ecosystems by 12% and overall (atmospheric and hydrologic) N losses to ecosystems by 4%. Were US citizens to consume protein at recommended rates, projected N excretion rates in 2055 would be 27% less than they are today, despite population growth. Optimizing US protein consumption to levels that meet human health standards has environmental benefits on par with improving wastewater treatment using existing technology, while also generating impactful economic benefits.

Vascular endothelial cells have a critical role in the maintenance of cardiovascular function. Evidence suggests that endothelial function may be compromised under conditions of magnesium deficiency, which increases vulnerability to inflammation. Whole genome transcription analysis was used to explore the acute (24 h) effects of magnesium on human umbilical vascular endothelial cells (HUVEC) cultured in low (0.1 mM) or high (5 mM) concentrations. With low magnesium 2728 transcripts were differentially expressed compared to the 1 mM control cultures and 3030 were differentially expressed with high magnesium. 615 transcripts were differentially expressed under both conditions, of which only 34 showed a concentration-dependent response. Analysis indicated that cellular organisation and biogenesis and key cellular processes such as apoptosis were impacted by both low and high conditions. High magnesium also influenced protein binding functions, intracellular signal transduction, metabolic and catalytic processes. Both conditions impacted on stress-related processes, in particular the inflammatory response. Key mediators of calcium-dependent regulation of gene expression were responsive to both high and low magnesium conditions. The HUVEC transcriptome is highly sensitive to acute changes in the concentration of magnesium in culture medium. The findings of this study support the view that whilst inflammation is an important process that is responsive to magnesium, the function of the endothelium may be impacted by other magnesium-induced changes including maintenance of cellular integrity, receptor expression and metabolic functions. The high proportion of transcripts that did not show a concentration-dependent response suggests variation in magnesium may elicit indirect changes, possibly mediated by other ions.

The chief intent of this review is to explain the different extraction techniques and efficiencies for the recovery of protein from food waste (FW) sources. Although FW is not a new concept, increasing concerns about chronic hunger, nutritional deficiency, food security, and sustainability have intensified attention on alternative and sustainable sources of protein for food and feed. Initiatives to extract and utilize protein from FW on a commercial scale have been undertaken, mainly in the developed countries, but they remain largely underutilized and generally suited for low-quality products. The current analysis reveals the extraction of protein from FW is a many-sided (complex) issue, and that identifies for a stronger and extensive integration of diverse extraction perspectives, focusing on nutritional quality, yield, and functionality of the isolated protein as a valued recycled ingredient.

As the anaerobic digestion of energy crops and crop residues becomes more widely applied for bioenergy production, planners and operators of biogas plants, and farmers who consider growing such crops, have a need for information on potential biogas and methane yields. A rich body of literature reports methane yields for a variety of such materials. These data have been obtained with different testing methods. This work elaborates an overview on the types of data source available and the methods that are commonly applied to determine the methane yield of an agricultural biomass, with a focus on European crops. Limitations regarding the transferability and generalisation of data are explored, and crop methane values presented across the literature are compared. Large variations were found for reported values, which can only partially be explained by the methods applied. Most notably, the intra-crop variation of methane yield (reported values for a single crop type) was higher than the inter-crop variation (variation between different crops). The pronounced differences in reported methane yields indicate that relying on results from individual assays of candidate materials is a high-risk approach for planning biogas operations, and the ranges of values such as those presented here are essential to provide a robust basis for estimation.

Background and aims: Non-alcoholic fatty liver disease (NAFLD) is a complex trait that has a global prevalence estimated as 25%. We aimed to identify the genetic variant underlying a four-generation family with progressive NAFLD leading to cirrhosis, decompensation and development of hepatocellular carcinoma in the absence of common risk factors such as obesity and type 2 diabetes. Methods: Exome sequencing and genome comparisons were used to identify the likely causal variant. We extensively characterised the clinical phenotype and post-prandial metabolic responses of family members with the identified novel variant in comparison to healthy non-carriers and wild type patients with NAFLD. Variant-expressing hepatocyte-like cells (HLCs) were derived from human induced pluripotent stem cells generated from homozygous donor skin fibroblasts. The phenotype was assessed using imaging, targeted RNA analysis and molecular expression arrays. Results: We identified a rare causal variant in MTTP, c.1691T>C p.I564T (rs745447480) encoding microsomal triglyceride transfer protein (MTP) associated with progressive non-alcoholic fatty liver disease, unrelated to metabolic syndrome. Although other described mutations in MTTP cause abetalipoproteinemia, neither homozygotes nor heterozygotes exhibited characteristic manifestations of this severe disease. HLCs derived from a homozygote donor had lower lipoprotein ApoB secretion, compared to wild type cells. Cytoplasmic triglyceride accumulation in HLCs triggered endoplasmic reticulum stress, secretion of pro-inflammatory mediators and production of reactive oxygen species. Conclusion: We have identified and characterized a rare causal variant in MTTP and homozygosity for MTTP p.I564T is associated with progressive NAFLD without any other manifestations of abetalipoproteinemia.

Global population growth, increased life expectancy and climate change are all impacting world's food systems. In industrialised countries, many individuals are consuming significantly more protein than needed to maintain health, with the majority being obtained from animal products, including meat, dairy, fish and other aquatic animals. Current animal production systems are responsible for a large proportion of land and fresh-water use, and directly contributing to climate change through the production of greenhouse gases. Overall, approximately 60% of the global protein produced is used for animal and fish feed. Concerns about their impact on both human, and planetary health, have led to calls to dramatically curb our consumption of animal products. Underutilised plants, insects and single-cell organisms are all actively being considered as alternative protein sources. Each present challenges that need to be met before they can become economically viable and safe alternatives for food or feed. Many plant species contain anti-nutritional factors that impair the digestion and absorption of protein and micronutrients. Insects represent a potentially rich source of high-quality protein although, questions remain relating to digestibility, allergenicity and biosecurity. Algae, fungi and bacteria are also a rich source of protein and there is growing interest in the development of 'cultured meat' using stem cell technology. For the foreseeable future, it appears likely that the 'protein-economy' will remain mixed. The present paper reviews progress and future opportunities in the development of novel protein sources as food and animal feed.

The chief intent of this review is to explain the different extraction techniques and efficiencies for the recovery of protein from food waste (FW) sources. Although FW is not a new concept, increasing concerns about chronic hunger, nutritional deficiency, food security, and sustainability have intensified attention on alternative and sustainable sources of protein for food and feed. Initiatives to extract and utilize protein from FW on a commercial scale have been undertaken, mainly in the developed countries, but they remain largely underutilized and generally suited for low-quality products. The current analysis reveals the extraction of protein from FW is a many-sided (complex) issue, and that identifies for a stronger and extensive integration of diverse extraction perspectives, focusing on nutritional quality, yield, and functionality of the isolated protein as a valued recycled ingredient.

Sustainable production of healthy food for a growing global population, in the face of the uncertainties of climate change, represents a major challenge for the coming decade. Livestock provide food with high nutritional value but are frequently fed on human-edible crops and are associated with significant production of greenhouse gases. Recent years have seen increasing interest in the farming of insects as a sustainable source of human food, or as a replacement of ingredients such as soya or fishmeal in the feeds of terrestrial livestock or fish. This review provides an overview of insect physiology and growth regulation, considers the requirements for insect farming and mass production, and summarizes the nutritional value of the 10 most commonly studied insect species, before reviewing the literature on the use of insects as feed and food. We highlight the challenges required to develop a sustainable, safe, and affordable insect farming industry.