Review: Amino acid concentration of high protein food products and an overview of the current methods used to determine protein quality

Dairy, Plant, and Novel Proteins: Scientific and Technological Aspects

Alternative proteins have gained popularity as consumers look for foods that are healthy, nutritious, and sustainable. Plant proteins, precision fermentation-derived proteins, cell-cultured proteins, algal proteins, and mycoproteins are the major types of alternative proteins that have emerged in recent years. This review addresses the major alternative-protein categories and reviews their definitions, current market statuses, production methods, and regulations in different countries, safety assessments, nutrition statuses, functionalities and applications, and, finally, sensory properties and consumer perception. Knowledge relative to traditional dairy proteins is also addressed. Opportunities and challenges associated with these proteins are also discussed. Future research directions are proposed to better understand these technologies and to develop consumer-acceptable final products.

A multi-center prospective study of plant-based nutritional support in adult community-based patients at risk of disease-related malnutrition

Introduction

There is an emerging need for plant-based, vegan options for patients requiring nutritional support.

Methods

Twenty-four adults at risk of malnutrition (age: 59 years (SD 18); Sex: 18 female, 6 male; BMI: 19.0 kg/m2 (SD 3.3); multiple diagnoses) requiring plant-based nutritional support participated in a multi-center, prospective study of a (vegan suitable) multi-nutrient, ready-to-drink, oral nutritional supplement (ONS) [1.5 kcal/mL; 300 kcal, 12 g protein/200 mL bottle, mean prescription 275 mL/day (SD 115)] alongside dietary advice for 28 days. Compliance, anthropometry, malnutrition risk, dietary intake, appetite, acceptability, gastrointestinal (GI) tolerance, nutritional goal(s), and safety were assessed.

Results

Patients required a plant-based ONS due to personal preference/variety (33%), religious/cultural reasons (28%), veganism/reduce animal-derived consumption (17%), environmental/sustainability reasons (17%), and health reasons (5%). Compliance was 94% (SD 16). High risk of malnutrition ('MUST' score ≥ 2) reduced from 20 to 16 patients (p = 0.046). Body weight (+0.6 kg (SD 1.2), p = 0.02), BMI (+0.2 kg/m2 (SD 0.5), p = 0.03), total mean energy (+387 kcal/day (SD 416), p < 0.0001) and protein intake (+14 g/day (SD 39), p = 0.03), and the number of micronutrients meeting the UK reference nutrient intake (RNI) (7 vs. 14, p = 0.008) significantly increased. Appetite (Simplified Nutritional Appetite Questionnaire (SNAQ) score; p = 0.13) was maintained. Most GI symptoms were stable throughout the study (p > 0.06) with no serious adverse events related.

Discussion

This study highlights that plant-based nutrition support using a vegan-suitable plant-based ONS is highly complied with, improving the nutritional outcomes of patients at risk of malnutrition.

Associations of Meat and Fish/Seafood Intake with All-Cause and Cause-Specific Mortality from Three Prospective Cohort Studies in Korea

SCOPE

Animal protein intake among Koreans has recently increased. However, there is limited evidence on the association of meat and fish/seafood intake and mortality.

METHODS AND RESULTS

This study uses three representative prospective cohorts in Korea and 134,586 eligible participants are selected. Food intake is assessed using a food frequency questionnaire. Outcomes are classified as death from cardiovascular disease (CVD), cancer, and all-causes. Red meat intake shows a marginally negative association with all-cause mortality in the median intake group and a positive association in the highest intake group. Processed meat intake in the highest quintile group is positively associated with all-cause mortality compared to that of the lowest quintile group. Fish intake in the highest quintile group is negatively associated with CVD mortality in men, and all-cause mortality in women, compared to those in the lowest quintile group, while processed fish intake has unfavorable effects on mortality. In addition, substitution of one serving per week of red and processed meat, and processed fish with fish is negatively associated with all-cause and CVD mortality.

CONCLUSION

Reduction of red and processed meat, and processed fish consumption or replacement of these foods with fish may be beneficial for longevity in Korean adults.

Amino acid intake with protein food source and incident dyslipidemia in Korean adults from the Ansan and Ansung Study and the Health Examinee Study

Background

Dyslipidemia is a major risk factor for cardiovascular diseases and appropriate intake of amino acids may be helpful for the management of dyslipidemia. However, evidence of an association between amino acid intake and dyslipidemia in Korean adults is limited.

Objective

The purpose of this study was to investigate how the incidence of dyslipidemia in Korean adults is associated with the consumption of amino acids, essential and nonessential types, as well as the sources of these amino acids from food.

Methods

Data from 35,478 study participants without dyslipidemia at baseline from the Ansan and Ansung Study and the Health Examinee Study were used for the analysis. Dyslipidemia and its components such as hypertriglyceridemia, hypercholesterolemia, hyper-low-density lipoprotein (LDL) cholesterolemia and hypo-high-density lipoprotein (HDL) cholesterolemia were the main outcome in this study. The participants were categorized into quartiles, based on the intake of amino acids and plant-/animal-based proteins.

Results

On average, the follow-up period lasted for 5.7 years. The two major food groups that contributed to one-half of the intake for each type of amino acid were whole grain mixed rice and white rice. Compared to the lowest quartile group, the highest quartile groups of essential amino acid intake [men: hazard ratio (HR) = 0.78; 95% confidence interval (CI), 0.63-0.97; P for trend = 0.0088; women: HR = 0.86; 95% CI, 0.76-0.99; P for trend = 0.0201] and nonessential amino acid intake (men: HR = 0.75; 95% CI, 0.60-0.94; P for trend = 0.0069; women: HR = 0.81; 95% CI, 0.71-0.93; P for trend = 0.0024) had a decreased risk of dyslipidemia. Plant-based protein intake had a negative association and animal-based protein intake had a nonsignificant association with dyslipidemia after adjustment for energy-adjusted fat intake. Furthermore, the essential and nonessential amino acid intake showed stronger negative associations with dyslipidemia after further adjustment for energy-adjusted fat intake.

Conclusion

To conclude, the intake of amino acids may have a protective effect against dyslipidemia in Korean adults who are aged 40 years or older, regardless of their protein food sources.

Seasonal variation of population and individual dietary niche in the avivorous bat, Ia io

The variation in niche breadth can affect how species respond to environmental and resource changes. However, there is still no clear understanding of how seasonal variability in food resources impacts the variation of individual dietary diversity, thereby affecting the dynamics of a population's dietary niche breadth. Optimal foraging theory (OFT) and the niche variation hypothesis (NVH) predict that when food resources are limited, the population niche breadth will widen or narrow due to increased within-individual dietary diversity and individual specialization or reduced within-individual dietary diversity, respectively. Here, we used DNA metabarcoding to examine the composition and seasonality of diets of the avivorous bat Ia io. Furthermore, we investigated how the dietary niches changed among seasons and how the population niche breadth changed when the availability of insect resources was reduced in autumn. We found that there was differentiation in dietary niches among seasons and a low degree of overlap, and the decrease of insect resource availability and the emergence of ecological opportunities of nocturnal migratory birds might drive dietary niche shifts toward birds in I. io. However, the population's dietary niche breadth did not broaden by increasing the within-individual dietary diversity or individual specialization, but rather became narrower by reducing dietary diversity via predation on bird resources that served as an ecological opportunity when insect resources were scarce in autumn. Our findings were consistent with the predictions of OFT, because birds as prey for bats provided extremely different resources from those of insects in size and nutritional value. Our work highlights the importance of size and quality of prey resources along with other factors (i.e., physiological, behavioral, and life-history traits) in dietary niche variation.

Recent Advances in the Processing and Manufacturing of Plant-Based Meat

Plant protein technology is a core area of biotechnology to ease the problem of human protein demand. Plant-based meat based on plant protein technology is a growing concern by global consumers in alleviating environmental pollution, cutting down resources consumption, and improving animal welfare. Plant-based meat simulates the texture, taste, and appearance of animal meat by using protein, lipid, carbohydrate, and other plant nutrients as the main substances. This review summarizes the main components of plant-based meat, processing technology, standard formula, market competition, and formula and texture of future research directions. According to the existing methods of plant-based meat fiber forming, the development process and characteristics of four production processes and equipment of plant-based meat spinning, extrusion, shearing, and 3D printing are emphatically expounded. The processing principles and methods of different processing technologies in plant-based meat production are summarized. The production process and equipment of plant-based meat will pay more attention to the joint production of various processes to improve the defects of plant-based meat production process.

Revisiting Protein Quality Assessment to Include Alternative Proteins

The high demand for novel and existing sustainable protein sources (e.g., legumes, insects, algae, and cultured meat) to replace the animal-based sources is becoming crucial. This change in protein consumption calls for the re-evaluation of the current methods to assess their quality and bioavailability. The two conventional scores for PDCAAS (protein digestibility-corrected AA score) and DIAAS (Digestible Indispensable AA Score) have their limitations and have not been re-evaluated and updated to address plant and novel proteins' quality. We suggest a sensitive physiological preclinical model that can rapidly and confidently address proteins from different sources. Our model is based on the postnatal growth, a major parameter for development and health in children, that influenced by environmental nutritional and lifestyle factors. Our results demonstrate that, with an appropriate amount of protein in the diet, almost all tested proteins performed as well as casein, the animal source. However, upon restriction (10% of calories), all alternative sources did not accomplish normal growth performance. Surprisingly, when compared to PDCAAS and DIAAS parameters obtained from the literature, no correlations were found between growth performance and these parameters, demonstrating their limitations.

High moisture extrusion cooking of meat analogs: A review of mechanisms of protein texturization

High-moisture extrusion cooking (HMEC) is an efficient method for converting proteins and polysaccharides into fibrous structure that is used in the industrial production of meat analogs. The purpose of this review is to systematically evaluate current knowledge regarding the modification of protein structure including denaturation and reassembly upon extrusion processing and to correlate this understanding to the structure of the final products. Although there is no consensus on the relative importance of a certain type of bond on extrudates' structure, literature suggests that, regardless of moisture level, these linkages and interactions give rise to distinctive hierarchical order. Both noncovalent and disulfide bonds contribute to the extrudates' fibrous structure. At high water levels, hydrogen and disulfide bonds play a dominant role in extrudates' texture. The process parameters including cooking temperature, screw speed, and moisture content have significant albeit different levels of impact on the texturization process. Their correlation with the ingredients' physiochemical properties provides a greater insight into the process-structure-function relationship of meat analogs. The tendency of protein and polysaccharide blends to phase separate rather than produce a homogeneous mix is a particularly important aspect that leads to the formation of fibrous layers when extruded. This review shows that systematic studies are required to measure and explain synergistic and competitive interactions between proteins and other ingredients such as carbohydrates with a focus on their incompatibility. The wide range of plant protein source can be utilized in the HMEC process to produce texturized products, including meat analogs.

Antioxidant and Sensorial Properties: Meat Analogues versus Conventional Meat Products

Meat-product alternatives have become more popular among consumers, mainly due to concern for animal welfare and demand for more eco-friendly production. This study focused on the comparison between the antioxidant capacities of selected types of meat products and those of their plant-based alternatives. The analogues of the following products were analyzed: minced meat, burger, steak, Hungarian sausages, Frankfurter sausages and salami. Total polyphenol contents and antioxidant capacities and sensory profiles of the products were determined. The highest polyphenol content (1.85 mg Gallic acid/g) and antioxidant capacity values (DPPH: 41.80% inhibition, CUPRAC: 9.21 Trolox mmol/kg, FRAP: 7.51 mmol/g, ABTS: 7.45% inhibition) were observed in the analogue samples of Hungarian sausages due to the oat flour presence in these products. The results indicated that antioxidant properties of meat analogue products (plant sources) were superior compared to conventional meat products (produced from animal sources). The sensorial attributes indicated no significant (p > 0.05) differences in taste (except the Frankfurter sausages). The novelty of the study can be seen in the fact that it confirmed that the sensory properties of meat analogue products can be close to those of traditional meat products.

A Narrative Review of Alternative Protein Sources: Highlights on Meat, Fish, Egg and Dairy Analogues

The research and development of alternatives to meat (including fish) and dairy products for human consumption have been increasing in recent years. In the context of these alternatives, there is a diversity of products such as tofu, tempeh, seitan, pulses, algae, seeds, nuts and insects. Apart from these, some products require new technical processes such as needed by milk drink alternatives, mycoprotein and meat, cheese and fish analogues. The aim of these analogues is to mimic the physical and organoleptic properties of animal origin products through fibrous composition and mix of ingredients from vegetable sources using adequate technology, which allow providing similar texture and flavor. Using a narrative approach to review literature, the objectives of this paper are to systematize the arguments supporting the adoption of meat, eggs and dairy alternatives, to identify the diversity of alternatives to these products on the market, including the related technological processes, and to project the challenges that the food industry may face soon. From a total of 302 scientific papers identified in databases, 186 papers were considered. More research papers on products associated with alternatives to milk were found. Nevertheless, there are products that need more research as analogues to meat and dairy products. A general scheme that brings together the main reasons, resources and challenges that the food industry faces in this promising area of alternatives to meat and dairy products is presented.

Antibacterial activity of antimicrobial peptide gcDefb1 against foodborne pathogenic bacteria and its application in pork storage

Pork and its products are preferably contaminated by bacteria; thus, it is essential to develop low-cost, high-efficiency and biologically safe preservatives to prevent the growth of bacteria during storage. In the current study, grass carp β-defensin 1 (gcDefb1) was produced and purified from Pichia pastoris through the heterologous expression method. The in vitro antimicrobial assay demonstrated that yeast-derived gcDefb1 possesses a broad antibacterial spectrum, including both Gram-positive and -negative bacteria, and the MIC values against Escherichia coli ATCC 25,922 were as low as 30 μg/mL and showed no cytotoxicity or hemolytic activity. The bactericidal rate of gcDefb1 was less than 60 min by disrupting the cell membranes, and it inhibited the formation of bacterial biofilms. Moreover, gcDefb1 was used as a biopreservative for pork storage, indicating that the physicochemical and sensory qualities were improved. This study provides an efficient method to prepare and utilize gcDefb1 as a novel biopreservative.

Supplementary Information

The online version contains supplementary material available at 10.1007/s10068-022-01060-9.

Review: On-farm and processing factors affecting bovine carcass and meat quality

This paper reviews the current state of knowledge on beef carcass and meat quality, with particular emphasis on on-farm and processing factors associated with its high and inconsistent variability. The diversity of livestock systems comes from the diversity of breeds (dairy or beef), ages and gender (bulls, steers, heifers, cull cows) used to produce either mainly beef or beef and milk. In addition, there are factors linked to farming practices (including diet, especially grazing) which significantly influence the sensory, nutritional, technological and extrinsic (such as image) quality attributes of meat. These can become factors of positive differentiation when controlled by the application and certification of technical specifications. Finally, preslaughter (such as stress), slaughter (such as the chilling and hanging method of carcasses) and postslaughter (such as ageing, packaging and cooking) conditions have a strong influence on the microbiological, sensory, technological and image quality attributes of beef. In this review, potential synergisms or antagonisms between the different quality attributes are highlighted. For example, finishing cattle on grass, compared to indoor fattening on a high concentrate diet, has the advantage of producing leaner meat with a higher proportion of omega-3 fatty acids while exhibiting superior oxidative stability, but with the consequence of a darker meat colour and lower productivity, as well as higher seasonality and land surface requirements. Moreover, the control of on-farm factors is often guided by productivity (growth rate, feed conversion ratio) and carcass quality attributes (weight, conformation and fatness). Genetic selection has often been oriented in this direction, without taking other quality attributes into account. Finally, the interactions between all these factors (and especially between on-farm and slaughter or processing factors) are not considered in the quality grading schemes in European countries. This means that positive efforts at farm level may be mitigated or even eliminated by poor slaughtering or processing conditions. All these considerations explain why between-animal variability in quality can be high, even when animals come from the same farming system. The ability to predict the sensory and nutritional properties of meat according to production factors has become a major objective of the supply chain.

Impact of Hydrolysis, Acetylation or Succinylation on Functional Properties of Plant-Based Proteins: Patents, Regulations, and Future Trends

Nowadays, plant-based proteins are gaining momentum due to their wide availability, good amino acid content, and their market appeal. Unfortunately, these molecules usually have low water solubility, affecting other functional characteristics, such as foaming and emulsification, opening technological opportunities for research. Some plant-based protein applications rely on adjustments to final formulations and changing these chemical structures to produce new protein ingredients is also a path widely used in recent research. These modifications can be classified as physical or chemical, the latter being the most popular, and hydrolysis is one of the more widely reported modifications. This review explores the application of chemical modifications to plant-based proteins to improve techno-functional properties, when applied as part of food formulations. In addition, acetylation and succinylation, as the second and third most used processes, are discussed, including a deep analysis of their effects. Furthermore, since there is no concise compilation of patents associated with these technological efforts, some of the references that involve chemical modifications and current regulations used worldwide for novel foods produced with these technologies are included in this review. Finally, future perspectives for the chemical modification of proteins are discussed.

Legumes as basic ingredients in the production of dairy-free cheese alternatives: a review

Research into dairy-free alternative products, whether plant-based or cell-based, is growing fast and the food industry is facing a new challenge of creating innovative, nutritious, accessible, and natural dairy-free cheese alternatives. The market demand for these products is continuing to increase owing to more people choosing to reduce or eliminate meat and dairy products from their diet for health, environmental sustainability, and/or ethical reasons. This review investigates the current status of dairy product alternatives. Legume proteins have good technological properties and are cheap, which gives them a strong commercial potential to be used in plant-based cheese-like products. However, few legume proteins have been explored in the formulation, development, and manufacture of a fully dairy-free cheese because of their undesirable properties: heat stable anti-nutritional factors and a beany flavor. These can be alleviated by novel or traditional and economical techniques. The improvement and diversification of the formulation of legume-based cheese alternatives is strongly suggested as a low-cost step towards more sustainable food chains. © 2021 The Authors. Journal of The Science of Food and Agriculture published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.

Equivalent servings of free-range reindeer promote greater net protein balance compared to commercial beef

Wild game consumption has been associated with health benefits but the acute influence on human protein metabolism remains unknown. We compared feeding-induced responses of equivalent amounts of free-range reindeer (FR) and commercial beef (CB) on protein kinetics using stable isotope methodology. Seven participants (age: 40 ± 14 years; body mass index: 24 ± 3 kg/m2) completed two randomised studies, ingesting 2 oz of FR or CB. L-[ring 2H5]phenylalanine & L-[ring 2H2]tyrosine were delivered via primed, continuous intravenous infusion. Blood samples were collected during the basal period and following consumption of FR or CB. Feeding-induced changes in whole-body protein synthesis (PS), protein breakdown (PB), and net protein balance (NB) were determined via plasma sample isotope enrichment analysis by gas chromatography-mass spectrometry; plasma essential amino acid (EAA) concentrations were determined by liquid chromatography-electrospray ionisation-mass spectrometry. Plasma post-prandial EAA concentrations were higher with FR compared to CB (P < 0.05). The acute feeding-induced PS response was not different, but PB was reduced and contributed to a superior level of NB (P < 0.00001) in FR compared to CB. Our results demonstrate that FR may influence more favourable protein metabolism than CB. These data support potential health benefits of wild game onf whole-body protein.Abbreviations: BMI: body mass index; DIAAS: digestible indispensable amino acid score; CB: commercial beef; EAA: essential amino acids; FR: free-range reindeer; Ra: rate of appearance; UAF: University of Alaska Fairbanks; USDA: USA Department of Agriculture.

Brief Research Report: Estimation of the Protein Digestibility-Corrected Amino Acid Score of Defatted Walnuts

Introduction: Walnuts are considered a good source of essential fatty acids, which is unique among tree nuts. Walnuts are also composed of about 10–15% protein, but the quality of this protein has not been evaluated. Pistachios and almonds have been evaluated for their protein content using a protein digestibility-corrected amino acid score (PDCAAS), but it is unclear how the quality of protein in walnuts relates to that in other commonly consumed tree nuts. The objective of this study was to substantiate the protein quality of walnuts by determining their PDCAAS.

Methods: A small, 10-day dietary intervention trial was conducted using male Sprague-Dawley rats (n = 8, 4 per group) with two diets: a nitrogen-free diet and a diet containing protein exclusively from defatted walnuts. Feed intake and fecal output of nitrogen were measured to estimate the true protein digestibility, and the amino acid compositions of walnuts compared to child and adult populations were used to calculate amino acid scores (AAS) and PDCAAS.

Results: The true protein digestibility score of raw walnuts was calculated to be 86.22%. Raw walnuts contained 15.6 g protein/g walnut with AAS of 0.45 and 0.63 for children aged 6 months to 3 years and 3–10 years, respectively. For each population, a PDCAAS of 39 and 46% was calculated, respectively, using a protein conversion constant of 5.30. Using a protein constant of 6.25, a PDCAAS of 39% (6 months - 3 years) or 46% (3-10 years) was calculated.

Conclusions: This is the first known assessment of the PDCAAS of walnuts. Like almonds, they appear to have a low-to-moderate score, indicating they are not a quality source of protein.

Metabolic Characterization of Meat, Fish, and Soda Intake in Males: Secondary Results from a Randomized Inpatient Pilot Study

OBJECTIVE

This study aimed to evaluate whether a 12-week, weight-maintaining, macronutrient-stable dietary intervention that varies only by meat, fish, or soda consumption alters 24-hour energy expenditure (24hrEE) and substrate oxidation.

METHODS

Healthy males were recruited to participate in a 12-week inpatient study and were randomized to a weight-maintaining dietary intervention that contained varying combinations of meat (0% or 19%), fish (0% or 6%), or soda (0% or 14%) in a factorial design. Macronutrient composition across dietary intervention groups was as follows: 50% of energy from carbohydrates, 30% of energy from fat, and 20% of energy from protein. Whole-room indirect calorimetry at baseline and week 12 were used to measure 24hrEE and substrate oxidation.

RESULTS

Twenty-six males (mean [SEM], age: 46.6 [10.4] years; BMI: 26.9 [4.1] kg/m2 ) completed all measurements. Fish consumption resulted in higher 24hrEE by 126 (55) kcal/d compared with no fish consumption (P = 0.03), whereas 24hrEE for soda consumption was 132 (56) kcal/d (P = 0.03) lower. Approximately 80% of the decrease in 24hrEE with soda consumption was due to lower awake-inactive energy expenditure (EE; P = 0.001). No specific EE component accounted for the differences observed with fish consumption.

CONCLUSIONS

The data indicate that dietary sources of protein and carbohydrates appear to influence 24hrEE and inactive EE.

Enhancing the Nutritional Value of Red Meat through Genetic and Feeding Strategies

Consumption of red meat contributes to the intake of many essential nutrients in the human diet including protein, essential fatty acids, and several vitamins and trace minerals, with high iron content, particularly in meats with high myoglobin content. Demand for red meat continues to increase worldwide, particularly in developing countries where food nutrient density is a concern. Dietary and genetic manipulation of livestock can influence the nutritional value of meat products, providing opportunities to enhance the nutritional value of meat. Studies have demonstrated that changes in livestock nutrition and breeding strategies can alter the nutritional value of red meat. Traditional breeding strategies, such as genetic selection, have influenced multiple carcass and meat quality attributes relevant to the nutritional value of meat including muscle and fat deposition. However, limited studies have combined both genetic and nutritional approaches. Future studies aiming to manipulate the composition of fresh meat should aim to balance potential impacts on product quality and consumer perception. Furthermore, the rapidly emerging fields of phenomics, nutrigenomics, and integrative approaches, such as livestock precision farming and systems biology, may help better understand the opportunities to improve the nutritional value of meat under both experimental and commercial conditions.

A Significant Change in Free Amino Acids of Soybean (Glycine max L. Merr) through Ethylene Application

In this study, the changes in free amino acids of soybean leaves after ethylene application were characterized based on quantitative and metabolomic analyses. All essential and nonessential amino acids in soybean leaves were enhanced by fivefold (250 to 1284 mg/100 g) and sixfold (544 to 3478 mg/100 g), respectively, via ethylene application. In particular, it was found that asparagine is the main component, comprising approximately 41% of the total amino acids with a twenty-five fold increase (78 to 1971 mg/100 g). Moreover, arginine and branched chain amino acids (Val, Leu, and Ile) increased by about 14 and 2-5 times, respectively. The increase in free amino acid in stem was also similar to the leaves. The metabolites in treated and untreated soybean leaves were systematically identified by gas chromatography-mass spectrometry (GC-MS), and partial variance discriminant analysis (PLS-DA) scores and heat map analysis were given to understand the changes of each metabolite. The application of ethylene may provide good nutrient potential for soybean leaves.

Use of Soy-Based Formulas and Cow's Milk Allergy: Lights and Shadows

Soybean (Glycine max) is a species of legume native to East Asia and used in childhood diet for over 2,000 years in the East. Soy protein formulas have been available for almost a century. Nowadays, the increase in cow's milk allergy and vegetarian dietary preferences are driving consumers toward cow's milk alternatives. In this paper, we reviewed the nutritional composition of soy-based infant formula and discussed their possible use in pediatric age, mainly focusing on prevention and treatment of cow's milk allergy. Protein quality is determined by digestibility and amino acid content. Purified or concentrated vegetable proteins (e.g., soy protein and gluten) have high digestibility (>95%), similar to those of animal ones. For some intact vegetable products (e.g., whole cereals and pulses), protein digestibility is lower (80-90%). Food processing and heat treatment also influence protein digestibility. Considering these data, we tried to evaluate the possible use of soybean and derivatives in pediatric age, including the nutritional composition of soy formulas and the clinical indications for their use. Moreover, since plant-based beverages are being perceived as healthy by consumers and their use is growing on the market, we recommend that soy drink should not be used as a substitute for infant formulas or cow's milk in children younger than 24 months.

Animal Protein Intake Is Positively Associated with Metabolic Syndrome Risk Factors in Middle-Aged Korean Men

Few studies have examined the relationship of protein intake by food source with metabolic syndrome in Korean adults, even though animal food intake has increased. This study examined the association between plant and animal protein intake and metabolic syndrome among middle-aged Korean adults. A total of 13,485 subjects aged 30-64 years were selected from the 2013-2018 Korea National Health and Nutrition Examination Survey. Protein intake was assessed using 24-h dietary recall data and divided into quintiles. Men had a higher percentage of energy intake from animal protein (7.4%) than plant protein (6.9%). Men in the highest quintile group of animal protein intake had a higher prevalence of abdominal obesity (OR: 1.30, 95% CI: 1.00-1.70), reduced high-density lipoprotein cholesterol (HDL-C) (OR: 1.43, 95% CI: 1.07-1.90), and elevated fasting glucose (OR: 1.32, 95% CI: 1.01-1.74), after adjusting for covariates. Furthermore, stronger associations of animal protein intake with abdominal obesity were shown in men who consumed less than estimated energy requirements (OR: 1.60, 95% CI: 1.11-2.31). Plant protein intake was negatively associated with increased blood pressure in men. Neither animal nor plant protein intakes were significantly associated with any of the metabolic syndrome risk factors in women. The results imply that lower animal protein intake may be a beneficial factor for metabolic syndrome management in middle-aged Korean men.

QUALITY ASSESSMENT OF PROTEINS IN COOKED SAUSAGES WITH FOOD COMPOSITIONS

. In the article, the data are given of research carried out in vitro to determine the amino acid composition and the degree of digestibility of the reference and experimental samples of cooked sausage, with the use of the protein-containing composition developed. The protein digestibility-corrected amino acid score (PDCAAS) has been calculated to clarify the assimilation of amino acids that enter the body as part of proteins in experimental cooked sausage samples.It has been established that replacing a part of the meat raw material with the protein-containing composition in the formula of cooked sausages does not affect significantly the amino acid composition of the finished product. The addition of mechanically deboned poultry meat reduces the amount of such essential amino acids as isoleucine by 68 %, compared with the control formula, leucine by 38 %, and valine by 48 %. At the same time, the content of lysine significantly increases by 1.5 times.  The in vitro index of digestibility for an experimental sample of cooked sausages with protein-containing composition at the pepsinolysis stage is slightly reduced compared with the reference sample (by an average of 7 %). At the second stage of hydrolysis (trypsin enzyme), this parameter does not differ from the reference one. During the two stages of hydrolysis, this parameter, with mechanically deboned poultry meat introduced, decreased by an average of 20 %, compared with the reference sample.Calculated PDCAAS has allowed establishing that the true efficiency of proteins in cooked sausages is different from the in vitro index of digestibility, which is due to the presence of limiting values of the essential amino acids content in the product.