Higher Amino Acid Content Research Articles

Structural, physicochemical, and immune-enhancing properties of edible insect protein isolates from Protaetia brevitarsis larvae.

Edible insects are promising future food resources globally. Herein, the structural, physicochemical, and bio-functional properties of edible insect protein isolates (EPIs) extracted from Protaetia brevitarsis larvae were investigated. The results showed that EPIs have a high total essential amino acid content; moreover, β-sheet is the major secondary protein structure. The EPI protein solution was highly soluble and electrically stable and did not aggregate easily. In addition, EPIs exhibited immune-enhancing properties; EPI treatment of macrophages induced the activation of macrophages and consequently promoted the production of pro-inflammatory mediators (NO, TNF-α, and IL-1β). Moreover, macrophage activation of EPIs was confirmed to occur through the MAPK and NF-κB pathways. In conclusion, our results suggest that the isolated P. brevitarsis protein can be fully utilized as a functional food material and alternative protein source in the future food industry.

Optimization of enzymatic hydrolysis condition of edible bird’s nest crumbs by response surface methodology and determination of biochemical characteristics of the hydrolysate

Edible bird's nest (EBN) crumbs are the by-product of the bird's nest industry. Despite having lower economic value compared to the original material, EBN crumbs still maintain high protein and carbohydrate content. Therefore, this study aimed to determine the optimal hydrolysis condition for EBN crumbs using protease to achieve the maximum degree of hydrolysis (DH). Plackett Burman design was employed to identify the important factors. The results showed that enzyme loading, temperature and hydrolysis time had the strongest effect on the DH. These factors were subsequently subjected to the optimization study using central composite design (CCD) of response surface methodology (RSM). The optimized conditions for the enzymatic hydrolysis of EBN crumbs were at an enzyme loading of 4%, temperature of 51ºC, and hydrolysis time of 90 min. The experimental DH obtained at the optimized condition (63.5%) was close to the predicted DH (64.1%). The enzymatic hydrolysate prepared at the optimal condition showed relatively high amino acid concentration (151.6 ± 1.29 µg/mL) and radical scavenging activity (64.97 ± 0.79%) compared to the boiled sample with values of only 50.1 ± 2.43 µg/mL and 18.36 ± 0.17%, respectively. The resultant hydrolysate had no effect on some of the microorganisms employed in this study. The EBN crumbs hydrolysate inhibited tyrosinase activity with an IC50 of 70.22 µg/mL, greater than that of boiled EBN (IC50= 108.9 µg/mL). The results indicated that the EBN crumbs hydrolysate could be further applied in the cosmetic industry as a rich source of nutrients and bioactive compounds for the formulation of beauty products.

Amino acids induced modulations in linear PEO‐PPO‐PEO triblock copolymer microstructures and its exploration in prototypical drug solubilization

AbstractThis manuscript explains the effect of biologically important additives on the micellar behavior of an ethylene oxide‐propylene oxide (PEO101‐PPO56‐PEO101) based linear block copolymer, Poloxamer 407.The effect of common pharmaceutical excipients and three vital amino acids viz. alanine, glycine, and lysine (Ala, Gly, and Lys) is examined with the help of cloud point (CP), dynamic light scattering (DLS), and small angle neutron scattering (SANS) techniques. The drug solubilization ability for the copolymer was checked for two model drugs Quercetin (QCT) and Ibuprofen (IBU) with the help of high‐performance liquid chromatography (HPLC) in the presence/absence of additives such as Ala, Gly, and Lys. The observed results reveal that higher amino acid concentrations, favor the solubilization of drug which can potentially benefit the use of these biocompatible copolymers in pharmaceutical and biopharma industries.

Optimal temperature for culturing chicken satellite cells to enhance production yield and umami intensity of cultured meat

To investigate the optimal temperature at which to culture chicken muscle satellite cells (MSCs), to improve the production yield and umami intensity of cultured meat, chicken MSCs were cultured at 37, 39, 41, and 43 °C. The most active proliferation and greatest differentiation of MSCs was observed at 41 °C. A significantly shorter doubling time of MSCs and higher area percentage of differentiated myotubes and myofibers were observed at a culture temperature of 41 °C (p < 0.05). Consequently, the total amino acid content and free glutamic acid in cultured muscle tissue (CMT) at 41 °C was significantly higher than at other temperatures (p < 0.05). In addition, the umami and richness intensity of CMT was significantly higher at 41 °C than at other culture temperatures (p < 0.05). Results suggest that chicken MSCs proliferated more actively and differentiated optimally at 41 °C, resulting in a higher amino acid content and umami intensity of CMT.

Disruption of the amino acid transporter CsAAP2 inhibits auxin-mediated root development in cucumber.

Amino acid transporters are the principal mediators of organic nitrogen distribution within plants and are essential for plant growth and development. Despite this importance, relatively few amino acid transporter genes have been explored and elucidated in cucumber (Cucumis sativus). Here, a total of 86 amino acid transporter genes were identified in the cucumber genome. We further identified Amino Acid Permease (AAP) subfamily members that exhibited distinct expression patterns in different tissues. We found that the CsAAP2 as a candidate gene encoding a functional amino acid transporter is highly expressed in cucumber root vascular cells. CsAAP2 knockout lines exhibited arrested development of root meristem, which then caused the delayed initiation of lateral root and the inhibition of root elongation. What is more, the shoot growth of aap2 mutants was strongly retarded due to defects in cucumber root development. Moreover, aap2 mutants exhibited higher concentrations of amino acids and lignin in roots. We found that the mutant roots had a stronger ability to acidize medium. Furthermore, in the aap2 mutants, polar auxin transport was disrupted in the root tip, leading to high auxin levels in roots. Interestingly, slightly alkaline media rescued their severely reduced root growth by stimulating auxin pathway.

Incorporation of Buckwheat Flour at Different Particle Sizes and Distinctive Doses in Wheat Flour to Manufacture an Improved Wheat Bread.

This study explored the effect of substituting wheat flour (WF) with distinctive optimal doses of buckwheat flour (BF) corresponding to large, medium, and small particle sizes (PS), previously established based on an optimization process, on composite flour characteristics, dough rheology, and bread quality. The optimal dose for each PS was established in a previous study. The highest value for protein, lipid, mineral, and amino acids was found in the optimal composite flour with medium PS, with significant differences between those with large and small PS. The addition of BF in WF at doses corresponding to each fraction provides optimum rheological properties, with the large and medium PS providing higher performance compared to the small one. The same tendency was observed for volume and texture parameters of bread made from optimal composite flours with medium and large PS, respectively, but the crust and crumb lightness presented lower values than bread with small PS. Regarding the bread nutritional profile, the sample with medium PS possessed the highest protein, lipid, and ash content. Compared to the wheat bread, a considerably higher amino acid content, up to 21.22%, was found in bread made from optimal composite flours with medium and small PS, respectively. The bread samples with medium and large PS, respectively were superior in minerals, the value being up to 2.63 times higher compared to the control. Sensory characteristics results revealed that the bread samples containing 9.13% large and 10.57% medium PS were the most preferred by panelists. The results of this research make an important base to suitably develop wheat-buckwheat bread applications in the future.

Physicochemical, Biofunctional, Structural, Sensory, and Cooking Characteristics of Seaweed (Caulerpa racemosa) Incorporated Pasta

ABSTRACT The aim of the study is to incorporate seaweed powder (Caulerpa racemosa) at different percentages in pasta. The increasing level of seaweed in pasta increases the nutritional composition compared to control pasta. In seaweed incorporated pasta, FTIR analysis confirms the enrichment of seaweed polyphenols due to the presence of functional group in the wavenumber 3761.81 cm−1 and the microstructure studies exhibited a better protein starch network. Phenolic content and DPPH radical scavenging activity are also found to be enhanced. Sensorily, the 5% seaweed powder incorporated pasta was well accepted, with high amino acid and fatty acid contents, and high antioxidant properties.

Selected plants producing mucilage: Overview, composition, and their potential as functional ingredients in the development of plant-based foods

The increase in the preference for vegan and vegetarian diets is directly related to changing eating habits and the need for plant-based alternatives to animal-based products, which are better for health, due to the high content of essential amino acids and lipid profile rich in polyunsaturated fatty acids, and have lower environmental impacts. In this scenario, there is a growing demand for plant-based foods, making it necessary to find new plant-based ingredients for application in foods and beverages. Flaxseed, chia seed, and Barbados gooseberry contain mucilage, a component with potential application in plant-based products. These hydrocolloids can be used as gelling agents, texture modifiers, stabilizers, and emulsifiers in solid and semi-solid foods. This review presents the extraction, characterization, and application of flaxseed, chia seed, and Barbados gooseberry mucilage for use in plant-based foods. It was found that mucilage composition varies due to the extraction method used, extraction conditions, and geographic location of the seed or leaf. However, applications in plant-based foods are currently limited, mainly focused on applying chia mucilage in bakery products and packaging. Research on applying flaxseed and Barbados gooseberry mucilage to plant-based products is limited, though it has been shown to have potential applications in packaging. Mucilage may also increase the nutritional profile of the product and provide better technological, functional, and sensory characteristics. Therefore, because of mucilage's excellent functional and technological properties, it is a promising candidate to act as an ingredient in plant-based food products.

Recent Advances in the Incorporation of Polysaccharides with Antioxidant and Antibacterial Functions to Preserve the Quality and Shelf Life of Meat Products.

Meat and meat products are susceptible to various types of natural processes such as oxidative degradation due to their high content of protein and essential amino acids. However, finding solutions to maintain the nutritional and sensory quality of meat and meat products is unavoidable. Hence, there is a pressing need to investigate alternatives to synthetic preservatives, focusing on active biomolecules of natural provenance. Polysaccharides are natural polymers of various sources that exhibit antibacterial and antioxidant properties via a variety of mechanisms, owing to their diversity and structural variation. For this reason, these biomolecules are widely studied in order to improve texture, inhibit the growth of pathogens, and improve the oxidative stability and sensory characteristics of meat products. However, the literature has not addressed their biological activity in meat and meat products. This review summarizes the various sources of polysaccharides, their antioxidant and antibacterial activities (mainly against pathogenic food strains), and their use as natural preservatives to replace synthetic additives in meat and meat products. Special attention is given to the use of polysaccharides to improve the nutritional value of meat, resulting in more nutrient-rich meat products with higher polysaccharide content and less salt, nitrites/nitrates, and cholesterol.

Metabolomics and transcriptomics strategies to reveal the mechanism of diversity of maize kernel color and quality

BackgroundMaize has many kernel colors, from white to dark black. However, research on the color and nutritional quality of the different varieties is limited. The color of the maize grain is an important characteristic. Colored maize is rich in nutrients, which have received attention for their role in diet-related chronic diseases and have different degrees of anti-stress protection for animal and human health.MethodsA comprehensive metabolome (LC-MS/MS) and transcriptome analysis was performed in this study to compare different colored maize varieties from the perspective of multiple recombination in order to study the nutritional value of maize with different colors and the molecular mechanism of color formation.ResultsMaize kernels with diverse colors contain different types of health-promoting compounds, highlighting that different maize varieties can be used as functional foods according to human needs. Among them, red-purple and purple-black maize contain more flavonoids than white and yellow kernels. Purple-black kernels have a high content of amino acids and nucleotides, while red-purple kernels significantly accumulate sugar alcohols and lipids.ConclusionOur study can provide insights for improving people’s diets and provide a theoretical basis for the study of food structure for chronic diseases.

Fermented extract of mealworm (Tenebrio molitor larvae) as a dietary protein source modulates hepatic proteomic profiles in C57BLKS/J-db/db mice

This study hypothesised that fermented mealworm extract (TMP) with higher amino acid contents than nonfermented extract can be used as a dietary protein source for type 2 diabetes mellitus, and compared its effects with casein (CA) using C57BLKS/J-db/db mice. TMP marginally lowered serum insulin and leptin levels and hepatic triglyceride, and lipid droplets compared with CA group. Proteomic analysis showed that 14 proteins (H4C1, CYB5A, ANXA5, RGN, 40S ribosomal protein, Atp2, PDI, GRP78, RDX, GCH1, LDHA, GNMT, ACAA2, and UROC1) were up-regulated and 8 proteins (UQCRC1, Txndc5, SBP2, HSPA8, PHB, TF, PC, and PK) were down-regulated in the CA group compared to the normal mice. However, TMP significantly down-regulated ANXA5, RGN, Atp2, PDI, RDX, LDHA, ACAA2, and UROC1, and up-regulated UQCRC1, PHB, TF, and PK. These proteins are related to glycolysis, lactate production, fatty acid β-oxidation, oxidative stress, and endoplasmic reticulum stress. These results suggest that TMP is a potential protein source that can replace CA in type 2 diabetes.

Очищення стічних вод пивоварної галузі з використанням технології метанового бродіння

The brewing industry generates a large amount of secondary material resources, namely: excess brewer's yeast, malt grain, malt sprouts, grain waste, protein sludge and a large amount of wastewater with varying degrees of organic pollution. These wastes contain a complex of nutrients, minerals and biologically active substances. Some of them (brewer's yeast, malt grain) are used as feed additives to the diet of farm animals as part of compound feed or in their native form. The brewing industry is a branch of food industry with a high degree of water consumption and, accordingly, a large amount of wastewater generated in the production process. Wastewater from the brewing industry belongs to the category of highly polluted, therefore, for their effective cleaning, it is necessary to use suitable and economically beneficial technologies. Substances dissolved in water cannot be filtered or precipitated using coagulants, removed using flotation, etc. Some of the impurities, for example, proteins, can be remo ved by physical and chemical methods, but the main part of them is in the solution. Effective cleaning is possible only if complex compounds are destroyed directly in the wastewater. Existing cleaning technologies using physical and chemical methods are imperfect because they have low cleaning rates. The best option for brewery wastewater treatment technology is the use of biotechnological cleaning methods. Such methods include methane fermentation. Methane fermentation is an anaerobic biochemical process that occurs under the influence of microorganisms of the genus Methanobacterium. This process leads to a significant reduction in the level of sewage pollution. The final products of methane fermentation are biogas and microbial protein with a high content of essential aminoacids. For wastewater treatment of the brewing industry the use of methane fermentation technology was proposed, the final products of which are highly purified wastewater and biogas

Effects of hyperprotein diet on anxiety, haemodynamics and morphofunctional aspects of the heart of Wistar rats.

What is the central question of this study? The consumption of a high-protein diet has been associated with an anxiogenic factor that can influence anxiety and possible cardiovascular changes: does the consumption of a high-protein diet interfere with anxiety, haemodynamics and morphofunctional aspects of the heart of Wistar rats? What is the main finding and its importance? Our study showed that the high-protein diet did not interfere with anxiety and haemodynamics. The animals in the hyperproteic group showed positive heart adaptations characterized by less work and lower heart rate without impairing ejection fraction and systemic blood pressure. Anxiety is a mechanism preparatory to a response in situations of threat and danger, involving behavioural, affective and physiological factors. Protein-based foods have a high concentration of amino acids which perform multiple functions, including in the biosynthesis of excitatory transmitters for the central nervous system. In recent years, adherence to high-protein diets has been gaining ground in society, on the basis that it brings benefits to the musculoskeletal system and cardiovascular health. The aim of the present study was to investigate the effect of a high-protein diet in a state of anxiety and to investigate morphofunctional cardiovascular effects of a high-protein diet in Wistar rats. The experiment lasted 8weeks and two groups of male rats were submitted to either a normoproteic or a hyperproteic diet. Anxiety was assessed using the plus maze test and cardiovascular morphofunctional aspects using transthoracic echocardiography and invasive measurements of femoral blood pressure. There was no statistically significant difference in the anxiety test, but the hyperproteic group was more agitated, with greater displacement during the test. Changes were found in systolic and end-diastolic volume, left ventricular diameter in systole and heart rate, which were significantly lower in the hyperproteic group, and there was an increase in the thickness of the interventricular septum in diastole. The results showed no influence of the higher protein diet on the animals' anxiety, body weight and haemodynamics.

Amino Acids Drive the Deterministic Assembly Process of Fungal Community and Affect the Flavor Metabolites in Baijiu Fermentation.

Nutrient fluctuation is ubiquitous in fermentation ecosystems. However, the microbial community assembly mechanism and metabolic characteristics in response to nutrient variation are still unclear. Here, we used Baijiu fermentation as a case example to study the responses of microbial community assembly and metabolic characteristics to the variation of amino acids using high-throughput sequencing and metatranscriptomics analyses. We chose two fermentation groups (group A with low amino acid and group B with high amino acid contents). The two groups showed similar succession patterns in the bacterial community, whereas they showed different succession in the fungal community wherein Pichia was dominant in group A and Zygosaccharomyces was dominant in group B. The β-nearest taxon index (βNTI) revealed that bacterial community was randomly formed, whereas fungal community assembly was a deterministic process. Variance partitioning analysis and redundancy analysis revealed that amino acids showed the largest contribution to the fungal community (37.64%, P = 0.005) and were more tightly associated with it in group B. Further study revealed that serine was positively related to Zygosaccharomyces and promoted its growth and ethanol production. Metatranscriptomic analysis revealed that the differential metabolic pathways between the two groups mainly included carbohydrate metabolism and amino acid metabolism, which explained the differences of ethanol production and volatile metabolites (such as isoamylol, isobutanol, and 2-methyl-1-butanol). Then these metabolic pathways were constructed and related gene expression and active microorganisms were listed. Our study provides a systematical understanding of the roles of amino acids in both ecological maintenance and flavor metabolism in fermentation ecosystems. IMPORTANCE In spontaneous fermented foods production, nutrient fluctuation is a critical factor affecting microbial community assembly and metabolic function. Revealing the microbial community assembly mechanism and how it regulates its metabolic characteristics in response to nutrient variation is helpful to the management of the fermentation process. This study provides a systematical understanding of the effect of amino acids on the microbial community assembly and flavor metabolisms using Baijiu fermentation as a case example. The data of this study highlight the importance of the nutrient management in fermentation ecosystems.

Metabolic Variations among Three New Tea Varieties Cultivated in Shandong, China.

Cultivar identification is a necessary step in tea breeding programs. Rapid identification methods would greatly improve these breeding processes. To preliminarily identify the three new Lucha tea varieties (LC6, LC7, and LC17) cultivated in Shandong, we measured their main agronomic characters and biochemical components. Then, we analyzed the metabolic profiles of these tea varieties and Fuding Dabaicha (FD) using a UPLC-ESI-MS/MS system. Their biochemical components indicated that the Lucha varieties had excellent varietal characteristics, with higher amino acid contents. Furthermore, secondary metabolism changed a lot in the Lucha tea varieties compared with that in the FD, with their accumulations of flavonoids and phenolic acids showing significant differences. These differential flavonoids were dominated by flavones and flavanone, flavonols, flavonoid carbonosides, and flavanols monomer. Flavanols especially, including epicatechin glucoside, epicatechin-3-(3″-O-methyl)gallate, epigallocatechin-3-O-(3,5-O-dimethyl)gallate, and epitheaflavic acid-3-O-Gallate, showed higher levels in the Lucha varieties. The phenolic acids containing caffeoyl groups showed higher levels in the Lucha varieties than those in the FD, while those containing galloyl groups showed a reverse pattern. Nitrogen metabolism, including amino acids, also showed obvious differences between the Lucha varieties and FD. The differential amino acids were mainly higher in the Lucha varieties, including 5-L-glutamyl-L-amino acid, N-monomethyl-L-arginine, and N-α-acetyl-L-ornithine. By using these approaches, we found that LC6, LC7, and LC17 were excellent varieties with a high yield and high quality for making green teas in Shandong.

Electron Attachment to DNA: The Protective Role of Amino Acids.

We have studied the effect of amino acids on the electron attachment properties of a DNA nucleobase, with cytosine as a model system. The equation of motion coupled cluster theory with an extended basis set has been used to simulate the electron-attached state of the DNA model system. Arginine, alanine, lysine, and glycine are the four amino acids considered to investigate their role in electron attachment to a DNA nucleobase. The electron attachment to cytosine in all the four cytosine-amino acid gas-phase dimer complexes follows a doorway mechanism, where the electron gets transferred from the initial dipole-bound doorway state to the final nucleobase-bound state through the mixing of electronic and nuclear degrees of freedom. When cytosine is bulk-solvated with glycine, the glycine-bound state acts as the doorway state, where the initial electron density is localized on the bulk amino acid and away from the nucleobase, thus leading to the physical shielding of the nucleobase from the incoming electron. At the same time, the presence of amino acids can increase the stability of the nucleobase-bound anionic state, which can suppress the sugar-phosphate bond rupture caused by dissociative electron attachment to DNA.

The study of nutritional value and microbiological characteristics of brine cheese with vegetable additive

This article investigated brine cheeses' nutritional value and safety by adding vegetable additives (dry powder of white cabbage and coriander). Brynza brine cheese was used as the basis for the recipe. By the chemical composition of the cheese with vegetable, additives has a significantly higher protein content (26.27 g/100g), while the fat content is lower (14.98 g/100g). There is a high content of amino acids and fatty acids (PUFA 6%, MUFA 24%). During prolonged storage of brine cheese, water activity aw decreases in control from 0.997 to 0.990, mass fraction of moisture increases from 60% to 62.5%, in the brine cheese with vegetable additives aw from 0.998 to 0.991, mass fraction of moisture from 61.1% to 63.7%.The use of vegetable additives in the formulation of cheeses does not affect the deterioration of microbiological parameters compared to the control sample. As a result of experimental studies, the shelf life of brine cheese with vegetable additives is 8-10 days.

Production of dried tomato powder with a high concentration of functional components and nutrients

The use of conventional drying methods for dehydrating vegetables and fruits with high sugar, amino acid, and moisture content is not feasible. Under extreme conditions, drying reduces the amount of functional ingredients present in these vegetables and fruits. Recently, there has been an increasing demand for powdered tomatoes because of their nutritional and functional components. This study aimed to evaluate tomato drying under normal pressure and low-temperature conditions, to efficiently reduce water content without compromising on product quality. A convection dryer, most widely used in food factories, was used in this study. This equipment uses a low temperature zone not normally used for drying, and processes the raw material to increase the drying area for rapid drying. The proposed method was validated by comparing the moisture and functional component contents, and the antioxidant activity of the dried product with those of the dried product obtained via freeze-drying. The results suggest that the proposed low-temperature drying method can produce functional dried food at food processing sites faster than using freeze-drying, with a residual rate of functional ingredients exceeding 90 %. Thus, low-temperature drying can be used as a simple and cost-effective method for the production of uniform dry tomato powder.

Bioprocessing to Preserve and Improve Microalgae Nutritional and Functional Potential: Novel Insight and Perspectives

Microalgae are aquatic unicellular microorganisms and, although various species are approved for human consumption, Arthrospira and Chlorella are the most widespread. Several nutritional and functional properties have been bestowed to microalgae principal micro- and macro-nutrients, with antioxidant, immunomodulatory and anticancer being the most common. The many references to their potential as a food of the future is mainly ascribed to the high protein and essential amino acid content, but they are also a source of pigments, lipids, sterols, polysaccharides, vitamins, and phenolic compounds with positive effects on human health. Nevertheless, microalgae use is often hindered by unpleasant color and flavor and several strategies have been sought to minimize such challenges. This review provides an overview of the strategies so far proposed and the main nutritional and functional characteristic of microalgae and the foods made thereof. Processing treatments have been used to enrich microalgae-derived substrates in compounds with antioxidant, antimicrobial, and anti-hypertensive properties. Extraction, microencapsulation, enzymatic treatments, and fermentation are the most common, each with their own pros and cons. Yet, for microalgae to be the food of the future, more effort should be put into finding the right pre-treatments that can allow the use of the whole biomass and be cost-effective while bringing about features that go beyond the mere increase of proteins.

Amino acid score of some products for younger school children nutrition

Introduction. Wholesome nutrition is one of the most important factors in shaping a person's somatic and mental health. Eating habits are formed in childhood and consolidated in adulthood. They can also have an impact on the development of future chronic diseases, such as metabolic syndrome, type 2 diabetes, cardiovascular diseases. The purpose of the work is to evaluate the amino acid score of the main food products of children of primary school age.&#x0D; Material and methods. The research was carried out during 2016 - 2021. Food menus for 1000 of children aged 6-9 years old living in the South of Ukraine (cities Odessa and Mykolaiv, suburban villages and villages far from the regional centres). The study was carried out during the spring-summer (May-June) and autumn-winter (November-December). Field studies of the amino acid content in 24 products, which were included in the first two deciles in terms of frequency of consumption, were also conducted. The results. The distribution of food products was marked by a certain constancy and depended little on the season of the year. Most foods are a major source of carbohydrates. Only 8 out of 24 products were a source of protein and essential amino acids. The overall consumption of protein-rich foods by younger schoolchildren was low. Conclusion. Children 6-10 years old should consume protein in the amount of 0.95 g/kg/day. Our research shows that even such an understated standard of need may not be fulfilled under the current state of affairs. The main sources of protein for children of primary school age in Southern Ukraine are milk, cheese, chicken, river fish and legumes. Dairy products, eggs and chicken have the highest value in terms of amino acid content, and pork has the lowest value. Legumes have a high amino acid content, but they are inferior to products of animal origin.