Self-assembled α-lactalbumin nanostructures: encapsulation and controlled release of bioactive molecules in gastrointestinal in vitro model.

BACKGROUND: Implementing encapsulation techniques is pivotal in safeguarding bioactive molecules against environmental conditions for drug delivery systems. Moreover, the food-grade nanocarrier is a delivery system and food ingredient crucial in creating nutraceutical foods. Nano α-lactalbumin has been shown to be a promissory nanocarrier for hydrophobic molecules. Furthermore, the nanoprotein can enhance the tecno-functional properties of food such as foam and emulsion. The present study investigated the nanostructured α-lactalbumin protein (nano α-la) as a delivery and controlled release system for bioactive molecules in a gastric-intestinal in vitro mimic system. RESULTS: The nano α-la was synthesized by a low self-assembly technique, changing the solution ionic strength by NaCl and obtaining nano α-la 191.10 ± 21.33 nm and a spherical shape. The nano α-la showed higher encapsulation efficiency and loading capacity for quercetin than riboflavin, a potential carrier for hydrophobic compounds. Thermal analysis of nano α-la resulted in a ΔH of -1480 J g-1 for denaturation at 57.44 °C. The nanostructure formed by self-assembly modifies the foam volume increment and stability. Also, differences between nano and native proteins in emulsion activity and stability were noticed. The release profile in vitro showed that the nano α-la could not hold the molecules in gastric fluid. The Weibull and Korsmeyer-Peppas model better fits the release profile behavior in the studied fluids. CONCLUSION: The present study shows the possibility of nano α-la as an alternative to molecule delivery systems and nutraceutical foods' formulation because of the high capacity to encapsulate hydrophobic molecules and the improvement of techno-functional properties. However, the nanocarrier is not perfectly suitable for the sustainable delivery of molecules in the gastrointestinal fluid, demanding improvements in the nanocarrier. © 2024 Society of Chemical Industry.

Encapsulation of Cinnamaldehyde and Vanillin as a Strategy to Increase Their Antimicrobial Activity.

Many studies have suggested that the encapsulation of natural antimicrobials increases their antimicrobial activity. In this sense, the objective was to study the inactivation of microorganisms with encapsulated cinnamaldehyde and vanillin (E-CIN and E-VN), in comparison with the unencapsulated antimicrobials (CIN and VN) in protein beverages. Additionally, the microbial response was quantified through mathematical modeling. Cinnamaldehyde and vanillin were encapsulated using whey protein concentrate (WPC) as the encapsulating agent. The effectiveness at inactivating Escherichia coli, Listeria innocua, and Saccharomyces cerevisiae was evaluated in a protein-apple juice beverage during storage (4 °C). Encapsulation increased the effectiveness of cinnamaldehyde, reaching reductions of 1.8, 3.3, and 5.3 log CFU/mL in E. coli, L. innocua, and S. cerevisiae, respectively, while vanillin encapsulation had little effect on antimicrobial activity, reducing by 0.5, 1.4, and 1.1 log cycles, respectively. The combined treatments (E-CIN + E-VN) had an additive effect in reducing E. coli and a synergistic effect against S. cerevisiae. The Gompertz model was more versatile and better described the biphasic curves, whereas the Weibull model complemented the information regarding the spectrum of resistances within the microbial population. In conclusion, the encapsulation of cinnamaldehyde with WPC enhanced its activity. However, further studies are necessary to improve the antimicrobial activity of vanillin.

Chilean Market Protein Shakes Composition.

Understanding the nutritional content of protein supplements is crucial for optimal nutritional planning among athletes and other people. Distribution of macronutrients and aminograms in the main products available in the national Chilean market remains unknown. A descriptive cross-sectional study was conducted to identify the main protein supplements available in the Chilean market. Information on macronutrients and aminograms from the nutritional labels of each product was extracted. The analysis considered the content per portion and per 100 g. Cluster analysis models and graphical representations were explored. Eighty protein shakes were assessed in the Santiago de Chile market. The median protein dosage was 32 g (range from 25 to 52), and the median energy value stood at 390 kcal (range from 312 to 514). The median protein content per 100 g of product was found to be 75 g (range from 42.5 to 97.2). The combined median concentration of amino acids was 4749.75 mg. Among these, the essential amino acid L-Tryptophan exhibited the lowest concentration at 1591.50 mg, while the conditional amino acid L-Glutamine had the highest median concentration at 17,336 mg. There was a significant prevalence of animal-derived products, placing specific emphasis on protein supplements that feature elevated levels of the amino acids L-Glutamine and L-Leucine.

Açaí Flan, A Functional Food with Lacticaseibacillus rhamnosus HN001 Probiotic: Physicochemical Characteristics, Probiotic Survival, Sensory Acceptance and Consumer Perception.

Research background: Açaí berry is rich in antioxidant compounds and is therefore closely associated with beneficial health effects. In this study, we aim to investigate the potential of using Lacticaseibacillus rhamnosus HN001 as a probiotic culture on açaí flan. Experimental approach: The chemical composition, physicochemical and microbiological characteristics, and sensory acceptance during refrigerated storage (5 °C for 42 days) of flan were investigated. In addition, the consumer perception of the product was evaluated using word association when consumers were shown a photo of the product with or without the added ingredients accompanied with a brief description of the product. Results and conclusions: The flan had a suitable chemical composition, mainly carbohydrates and proteins, probiotic viability reached 8 log CFU/g in the product and 4 log CFU/g after gastrointestinal simulation, typical açaí coloration, significant antioxidant activity and high sensory acceptability. The information about the ingredients and properties of the products increased the health value and positive feelings of the consumers towards the product. Novelty and scientific contribution: Açaí flan has proven to be a suitable carrier for L. rhamnosus HN001 as a probiotic culture, further enhancing the characteristic beneficial properties of the fruit. Therefore, combining this information with marketing strategies that inform consumers about the benefits of the product can further improve its acceptance. As far as we know, this is the first study on açaí flan with added probiotic culture.

Viability of Lactobacillus reuteri DSM 17938 Encapsulated by Ionic Gelation during Refractance Window® Drying of a Strawberry Snack.

The selection of appropriate probiotic strains is vital for their successful inclusion in foods. These strains must withstand processing to reach consumers with ≥106 CFU/g, ensuring effective probiotic function. Achieving this in commercial products is challenging due to sensitivity to temperature during processing. In this work, Lactobacillus reuteri DSM 17938 was microencapsulated by ionic gelation (with alginate or pectin) followed by polymeric coating (with whey protein concentrate or chitosan). Then, such microcapsules were incorporated into a strawberry puree, which was subsequently dehydrated at three temperatures (40 °C, 45 °C, and 50 °C) by Refractance Window®. The ultimate aim was to demonstrate the efficacy of the proposed methods from a technological point of view. Kinetic curves of the probiotic's viability showed a high cell loading (>109 CFU/g). Additionally, an average encapsulation efficiency of 91% and a particle size of roughly 200 µm were found. A decrease in the viability of the microorganism was observed as drying temperature and time increased. As a demonstration of the above, in a particular case, drying at 45 °C and 50 °C, viable cells were found up to 165 min and 90 min, respectively; meanwhile, drying at 40 °C, viable cells were reported even after 240 min. The greatest viability preservation was achieved with Refractance Window® drying at 40 °C for 240 min when microcapsules coated with whey protein concentrate were incorporated into puree; this procedure showed great potential to produce dehydrated strawberry snacks with moisture (15%), water activity (aw < 0.6), and viability (≥106 CFU/g) suitable for functional foods. The membrane-stabilizing properties of whey protein concentrate could prevent cell damage. In contrast, probiotics in chitosan-coated capsules showed reduced viability, potentially due to antimicrobial properties and the formation of cracks. These findings signify a breakthrough in the production of dehydrated snacks with the addition of probiotics, addressing challenges in preserving the viability of these probiotics during processing; thus, opening the possibility for the development of a probiotic strawberry snack.

An Apple and Acáchul Berry Snack Rich in Bioaccessible Antioxidants and Folic Acid: A Healthy Alternative for Prenatal Diets.

A fruit leather (apple and acáchul berry) oriented toward women of reproductive age was developed. The snack was supplemented with an ingredient composed of folic acid (FA) and whey proteins (WPI) to ensure the required vitamin intake to prevent fetal neural tube defects. In order to generate a low-calorie snack, alternative sweeteners were used (stevia and maltitol). The fruit leather composition was determined. Also, an in vitro digestion process was carried out to evaluate the bioaccessibility of compounds with antioxidant capacity (AC), total polyphenols (TPCs), total monomeric anthocyanins (ACY), and FA. The quantification of FA was conducted by a microbiological method and by HPLC. The leather contained carbohydrates (70%) and antioxidant compounds, mainly from fruits. Bioaccessibility was high for AC (50%) and TPCs (90%), and low for ACY (17%). Regarding FA, bioaccessibility was higher for WPI-FA (50%) than for FA alone (37%), suggesting that WPI effectively protected the vitamin from processing and digestion. Furthermore, the product was shown to be non-cytotoxic in a Caco-2 cell model. The developed snack is an interesting option due to its low energy intake, no added sugar, and high content of bioactive compounds. Also, the supplementation with WPI-FA improved the conservation and bioaccessibility of FA.

Effects of whey protein supplementation on gut microbiota of Wistar rats with valproic acid-induced autism symptoms.

Aim: To evaluate the effects of whey protein (WP) supplementation (1.24 mg/g, 24 days) in rats with autism spectrum disorder (ASD) induced by valproic acid (400 mg/kg, single dose). Materials & methods: Wistar rats (14 days old) were divided into four groups: control, ASD, ASD plus WP and WP. Results: WP increased bacterial diversity and the number of colonies. Bacteria from the Firmicutes phylum were predominantly found in the supplemented groups (p < 0.05). WP also improved the animals' memory in the Y-maze test and decreased the time that male animals spent in the 'solitary chamber' (p < 0.05). Conclusion: WP supplementation positively influenced gut microbiota, along with memory.

Thousands of bacteria live in the human intestine. These bacteria help with many functions in the body and are so important that they can communicate with the brain. When the types and abundance of these bacteria change, brain activity can also change. This may be the case in some children with autism spectrum disorder (ASD), who may have an increase in harmful types of bacteria and a decrease in beneficial types of bacteria in the gut. Whey protein is a commonly used protein supplement for muscle growth. However, many studies have shown its benefits for gut bacteria. The authors investigated the effects of whey protein in animals with symptoms of ASD and showed that supplementation with whey protein increased the number of beneficial bacteria. In addition, the rats given whey protein had better memory. ASD-induced rats were less sociable, spending more time by themselves. However, male animals treated with whey protein spent less time alone. Supplementation with whey protein was beneficial for gut bacteria and memory in rats.

The Specific Encapsulation of Procyanidins from Litchi Peel and Coffee Pulp Extracts via Spray-Drying Using Green Polymers.

Polyphenols called procyanidins can be extracted from agro-industrial waste like litchi peel and coffee pulp. However, their efficacy is limited due to instability, which hinders both the bioavailability and preservation of their activity. This study aims to establish the ideal encapsulation conditions required to preserve the procyanidin properties found in extracts taken from litchi peel and coffee pulp. To attain the maximum procyanidin encapsulation efficacy (EE), the Taguchi method was utilized to streamline the spray-drying conditions for different wall materials-maltodextrin (MD), whey protein (WP), citrus pectin (CP), and skim milk (SM). The optimized conditions consisted of feed flow (3, 4.5, and 6 mL/min), temperature (125, 150, and 175 °C), and airflow (30, 35, and 40 m3/h). The microcapsules were characterized using ABTS, DPPH, lipoperoxidation, and scanning electron microscopy. Objective evaluations revealed that MD was the most effective encapsulation material for the litchi extract, whereas WP was the optimal option for the coffee extract. Of all the factors considered in the spray-drying process, feed flow had the strongest impact. The spray-drying process for the litchi peel extracts achieved high procyanidin encapsulation efficiencies at a feed flow rate of 4.5 mL/min, a temperature of 150 °C, and an airflow rate of 35 m3/h. Meanwhile, the coffee extract spray drying achieved similar results at a feed flow rate of 4.5 mL/min, a temperature of 175 °C, and an airflow rate of 40 m3/h. Encapsulation efficiencies of 98.1% and 93.6% were observed for the litchi and coffee extracts, respectively, under the mentioned optimal conditions. The microencapsulation process was successful in preserving the antioxidant properties of procyanidins. The microcapsules' size ranged from 2.6 to 3.2 micrometers. The results imply that the phenolic compounds present in the extracts function as effective antioxidant agents.

Effectiveness of Whey Protein Supplementation during Resistance Exercise Training on Skeletal Muscle Mass and Strength in Older People with Sarcopenia: A Systematic Review and Meta-Analysis.

OBJECTIVE: To determine the effectiveness of whey protein (WP) supplementation during resistance exercise training (RET) vs. RET with or without placebo supplementation on skeletal muscle mass, strength, and physical performance in older people with Sarcopenia. METHODS: Electronic searches in the PubMed, Embase, Scopus, Web of Science, LILACS, SPORTDiscus, Epistemonikos, and CINAHL databases were performed until 20 January 2023. Randomized clinical trials conducted on sarcopenic adults aged 60 or older were included. The studies had to compare the effectiveness of the addition of supplements based on concentrated, isolated, or hydrolyzed whey protein during RET and compare it with RET with or without placebo supplementation on skeletal muscle mass and strength changes. The study selection process, data extraction, and risk of bias assessment were carried out by two independent reviewers. RESULTS: Seven randomized clinical trials (591 participants) were included, and five of them provided data for quantitative synthesis. The overall pooled standardized mean difference (SMD) estimate showed a small effect size in favor of RET plus WP for skeletal muscle mass according to appendicular muscle index, with statistically significant differences compared with RET with or without the placebo group (SMD = 0.24; 95% CI, 0.05 to 0.42; p = 0.01; I2 = 0%, p = 0.42). The overall pooled mean difference (MD) estimate showed a significant difference of +2.31 kg (MD = 2.31 kg; 95% CI, 0.01 to 4.6; p = 0.05; I2 = 81%, p < 0.001) in handgrip strength in the RET plus WP group compared with the RET group with or without placebo. The narrative synthesis revealed discordance between the results of the studies on physical performance. CONCLUSIONS: WP supplementation during RET is more effective in increasing handgrip strength and skeletal muscle mass in older people with Sarcopenia compared with RET with or without placebo supplementation. However, the effect sizes were small, and the MD did not exceed the minimally important clinical difference. The quality of the evidence was low to very low according, to the GRADE approach. Further research is needed in this field.

Characterization of novel proteases identified by metagenomic analysis from dairy stabilization ponds.

Cheese whey is the main by-product of dairy industries. It is used as a raw material for other value-added products, like whey protein concentrate. By using enzymes, this product can be further treated to obtain new higher value products, like whey protein hydrolysates. Proteases (EC: 3.4) represent a large segment of industrial enzymes, since they are used in several industries, including food. In this work, we describe three novel enzymes identified using a metagenomic approach. Metagenomic DNA from dairy industry stabilization ponds were sequenced, and the predicted genes were compared against the MEROPS database, focusing on families commercially used to produce whey protein hydrolysates. From a total of 849 candidates, 10 were selected for cloning and expression and three showed activities with both the chromogenic substrate, azocasein, and whey proteins. Particularly, Pr05, an enzyme from the yet uncultured phylum Patescibacteria, showed activity that is comparable to a commercial protease. All these novel enzymes could represent an alternative for dairy industries to produce value-added products from industrial by-products. KEY POINTS: • Over 19,000 proteases were predicted in a sequence-based metagenomic analysis. • Three proteases were successfully expressed and showed activity with whey proteins. • The enzyme Pr05 showed hydrolysis profiles of interest for food industry.

Cytotoxicity, structural, conformational, and techno-functional properties of α-lactalbumin nanostructured aggregates.

Protein nanostructures can be used in food applications to improve the techno-functional properties of a food formulation. This study aims to find the best conditions for the production and conformational change of α-lactalbumin nanostructured aggregates. The criteria to determine the best operating conditions to produce α-lactalbumin nanostructured aggregates were intensification of foaming and emulsification, techno-functional proprieties, cytotoxic, and antibacterial activity of nanostructures compared with native α-lactalbumin. Conformational alterations occurred in the α-helix and sheet-ß protein structures. The size obtained by dynamic light scattering was 163.84 nm with a polydispersity index of 0.29. The nano protein improved the techno-functional property compared to the native protein. Additionally, nanostructures had no cytotoxic effect and were innocuous to bacterial activity. Thus, this study presents the best conditions to produce α-lactalbumin nanostructured aggregates with improved properties that allow new food industry applications.

The Influence of Whey Protein on Muscle Strength, Glycemic Control and Functional Tasks in Older Adults with Type 2 Diabetes Mellitus in a Resistance Exercise Program: Randomized and Triple Blind Clinical Trial.

OBJECTIVES: To evaluate the effect of whey protein (WP) supplementation associated with resistance training (RT) on glycemic control, functional tasks, muscle strength, and body composition in older adults living with type 2 diabetes mellitus (T2DM). Secondly, to evaluate the safety of the protocol for renal function. METHODS: The population comprised twenty-six older men living with T2DM (68.5 ± 11.5 years old). The participants were randomly assigned to the Protein Group (PG) and the Control Group (CG). The handgrip test and evolution of exercise loads, according to the Omni Resistance Exercise Scale, evaluated muscle strength. Functional tasks were assessed by force platform in three different protocols: Sit-to-Stand, Step/Quick Turn, and Step Up/Over. Body composition was evaluated by bioimpedance and glycemic control and renal function were assessed by biochemical analyses. Both groups performed RT for 12 weeks, twice a week, prioritizing large muscle groups. Protein supplementation was 20 g of whey protein isolate and the CG was supplemented with an isocaloric drink, containing 20 g of maltodextrin. RESULTS: There was a significant difference in muscle strength, according to the evolution of the exercise loads, but it was not confirmed in the handgrip test. However, there was no significant difference between the groups, regarding performance in functional tasks, glycemic control, or body composition. Renal function showed no alteration. CONCLUSION: The intake of 20 g of WP in older male adults living with T2DM did not increase the effect of RT on muscle strength, functional tasks, and glycemic control. The intervention was proven safe regarding renal function.

Physicochemical and structural characterization of whey protein concentrate-tomato pectin conjugates.

BACKGROUND: Protein-pectin conjugates, obtained through a controlled Maillard reaction in blends of precursors, are studied for their contribution to improving the emulsifying and thermal properties of proteins. The objective was to obtain a conjugate between whey protein concentrate (WPC) and non-conventional pectins extracted in acid (acid tomato pectin, ATP) and aqueous medium (water tomato pectin, WTP) from industrialized tomato residues (tomato waste, TW), characterize the conjugates and study their emulsion properties. The Maillard reaction was carried out at 60 °C and 75% relative humidity in blends with 2:1 proportions; 1:1 and 1:2 (mprotein :mpectin ) for 3, 6 and 12 days. Conjugates were compared concerning treated and untreated WPC. RESULTS: The WPC-ATP conjugate showed significant increases in color difference (ΔE). The electrophoresis profile of the conjugates showed diffuse bands of molecular weight between 37 and 250 kDa and a reduction in the intensity of bands characteristic of WPC (α-lactalbumin and ß-lactoglobulin). Thermal analysis showed an increase in the peak temperature and a reduction in the enthalpy change in protein denaturation, associated with the formation of conjugates. The infrared spectroscopy of the conjugates, in the amide III zone (1300-1100 cm-1 ), indicated an increase in the relative peak area associated with the unfolding and exhibition of the hydrophobic zones of the WPC fraction. The emulsions formulated with the conjugates showed a significant increase in the emulsifying stability index (ESI) (P < 0.05) concerning the treated and untreated WPC emulsions. CONCLUSION: The formation of conjugates increased the emulsifying properties and improved the thermal stability of WPC, showing an innovative and alternative food ingredient too. © 2023 Society of Chemical Industry.

Bioactive Antimicrobial Peptides from Food Proteins: Perspectives and Challenges for Controlling Foodborne Pathogens.

Bioactive peptides (BAPs) derived from food proteins have been extensively studied for their health benefits, majorly exploring their potential use as nutraceuticals and functional food components. These peptides possess a range of beneficial properties, including antihypertensive, antioxidant, immunomodulatory, and antibacterial activities, and are naturally present within dietary protein sequences. To release food-grade antimicrobial peptides (AMPs), enzymatic protein hydrolysis or microbial fermentation, such as with lactic acid bacteria (LAB), can be employed. The activity of AMPs is influenced by various structural characteristics, including the amino acid composition, three-dimensional conformation, liquid charge, putative domains, and resulting hydrophobicity. This review discusses the synthesis of BAPs and AMPs, their potential for controlling foodborne pathogens, their mechanisms of action, and the challenges and prospects faced by the food industry. BAPs can regulate gut microbiota by promoting the growth of beneficial bacteria or by directly inhibiting pathogenic microorganisms. LAB-promoted hydrolysis of dietary proteins occurs naturally in both the matrix and the gastrointestinal tract. However, several obstacles must be overcome before BAPs can replace antimicrobials in food production. These include the high manufacturing costs of current technologies, limited in vivo and matrix data, and the difficulties associated with standardization and commercial-scale production.

Complex coacervation and freeze drying using whey protein concentrate, soy protein isolate and arabic gum to improve the oxidative stability of chia oil.

BACKGROUND: Chia oil (CO) is popular for being the richest vegetable source of α-linolenic acid (60-66%). However, this content of polyunsaturated fatty acids (PUFA) limits the incorporation of bulk CO in food products due to its high probability of oxidation. This justifies the study of alternative wall materials for microencapsulation. No reports regarding the use of dairy protein/vegetable protein/polysaccharide blends as wall material for the microencapsulation of CO have been published. Therefore, this work analyzed the behavior of a whey protein concentrate (WPC)/soy protein isolate (SPI)/arabic gum (AG) blend as wall material. The complex coacervation (CC) process was studied: pH, 4.0; total solid content, 30% w/v; WPC/SPI/AG ratio, 8:1:1 w/w/w; stirring speed, 600 rpm; time, 30 min; room temperature. RESULTS: The oxidative stability index (OSI) of CO (3.25 ± 0.16 h) was significantly increased after microencapsulation (around four times higher). Furthermore, the well-known matrix-forming ability of AG and WPC helped increase the OSI of microencapsulated oils. Meanwhile, SPI contributed to the increase of the encapsulation efficiency due to its high viscosity. Enhanced properties were observed with CC: encapsulation efficiency (up to 79.88%), OSIs (from 11.25 to 12.52 h) and thermal stability of microcapsules given by the denaturation peak temperatures of WPC (from 77.12 to 86.00 °C). No significant differences were observed in the fatty acid composition of bulk and microencapsulated oils. CONCLUSION: Microcapsules developed from complex coacervates based on the ternary blend represent promising omega-3-rich carriers for being incorporated into functional foods.

Microencapsulation of marjoram essential oil as a food additive using sodium alginate and whey protein isolate.

Encapsulation techniques are generally used to preserve the volatile compounds of essential oils. This study aimed to evaluate the influence of process variables on the microencapsulation of marjoram essential oil (MEO) (Origanum majorana L.) by ionic gelation. The effect of sodium alginate concentration (0.5-2 g/100 mL), emulsifier concentration (0.5-2 g/100 mL whey protein isolate (WPI)), and cationic bath concentration (0.05-0.3 mol/L CaCl2) on the emulsions and beads properties were investigated, according to a rotatable central composite design. MEO chemical composition and antimicrobial activity were assessed. Emulsions were characterized for droplet size and viscosity, while the particles were analyzed for encapsulation efficiency, size and circularity, and morphology. High concentrations of alginate and WPI intensified the porous structure of the beads, reducing droplet mean diameter and encapsulation efficiency. High alginate concentrations also increased emulsion viscosity, affecting positively beads' circularity. The intermediate concentration of sodium alginate (1.25 g/100 mL), WPI (1.25 g/100 mL), and CaCl2 (0.175 mol/L) were selected as the most appropriate conditions to produce beads with satisfactory circularity and high encapsulation efficiency.

Whey protein and vitamin D supplementation in institutionalized older adults: A randomized trial.

Background: The increase in life expectancy and in the number of individuals over 60 years old brings new demands to health professionals and services based on the physiological changes that occur in this population. The aging process results in changes in body composition, increasing body fat and reducing muscle mass, in addition to a reduction in bone mass. Aim: The aim of this study was to examine the effect of whey protein and vitamin D supplementation on body composition and skeletal muscle in older adults living in long-term care facilities. Methods: This study is a double-blind randomized controlled trial. Thirty older adults (>60 years old) were randomized and allocated in three groups: group receiving resistance training and supplementation receiving resistance training, whey protein and vitamin D; group received resistance and placebo training receiving resistance training and placebo, and control group without any intervention. Body composition was measured by dual-energy X-ray absorptiometry at baseline, 12 weeks, and 24 weeks. Results: The mean age was 74.87 (± 8.14) years. A significant difference (p = 0.042) was observed between the group receiving resistance training and supplementation and control groups in relation to lean mass increase (kg) at 24 weeks. After 24 weeks of intervention, there was a significant increase in Relative index of muscle mass for the two groups that underwent resistance training, group received resistance and placebo training (p = 0.042) and group receiving resistance training and supplementation (p = 0.045), in relation to the control. Conclusion: Combined supplementation of whey protein and vitamin D with resistance training can significantly improve lean mass, total mass, and relative index of muscle mass in institutionalized older adults.

Effects of whey protein supplementation on adiposity, body weight, and glycemic parameters: A synthesis of evidence.

AIMS: The aim of this review was to analyze the evidence of whey protein supplementation on body weight, fat mass, lean mass and glycemic parameters in subjects with overweight or type 2 diabetes mellitus (T2DM) undergoing calorie restriction or with ad libitum intake. DATA SYNTHESIS: Overweight and obesity are considered risk factors for the development of chronic noncommunicable diseases such as T2DM. Calorie restriction is a dietary therapy that reduces weight and fat mass, promotes the improvement of glycemic parameters, and decreases muscle mass. The maintenance of muscle mass during weight loss is necessary in view of its implication in preventing chronic diseases and improving functional capacity and quality of life. The effects of increased protein consumption on attenuating muscle loss and reducing body fat during calorie restriction or ad libitum intake in overweight individuals are discussed. Some studies have demonstrated the positive effects of whey protein supplementation on improving satiety and postprandial glycemic control in short term; however, it remains unclear whether long-term whey protein supplementation can positively affect glycemic parameters. CONCLUSIONS: Although whey protein is considered to have a high nutritional quality, its effects in the treatment of overweight, obese individuals and those with T2DM undergoing calorie restriction or ad libitum intake are still inconclusive.

Efectos de la proteína whey, leucina y entrenamiento de fuerza en la composición corporal / Effects of whey protein, leucine and resistance training on body composition

INTRODUCCIÓN: Los deportistas y las personas activas que entrenan la fuerza para lograr un aumento de su masa muscular tienen requerimientos calóricos y proteicos aumentados, por esta razón emplean diversas estrategias como la suplementación con proteína whey aislada y aminoácidos aislados como la leucina después del entrenamiento sustentados en la premisa de que promueven el incremento en la síntesis de proteínas musculares, y por ende un aumento de la masa magra. OBJETIVO: Comparar cambios de la composición corporal aplicando el método de Absorciometría Dual de Rayos X (DEXA) en personas físicamente activas expuestas a un programa de entrenamiento de la fuerza con la suplementación de proteína whey aislada y/o leucina durante 12 semanas. METODOLOGÍA: estudio aleatorizado prospectivo longitudinal en un grupo de 10 varones físicamente activos, los cuales fueron asignados al azar en 3 grupos de suplementación con proteína whey aislada, leucina o la mezcla de ambas bajo el mismo protocolo de entrenamiento de la fuerza. Se evaluó la composición corporal en 3 momentos: semana 0, semana 6 y semana 12 de la intervención. RESULTADOS: En las condiciones evaluadas no se observaron cambios estadísticamente significativos de las variables de composición corporal y fuerza en los diferentes protocolos de suplementación: leucina, proteína whey aislada con leucina y proteína whey aislada. CONCLUSIONES: Se observaron resultados superiores de la masa magra y la fuerza en el grupo de la suplementación de proteína whey aislada con leucina con respecto a los demás grupos, cabe aclarar que por el tamaño de muestra no alcanzó a ser estadísticamente significativo.

INTRODUCTION: Athletes and active people who work hard to increase their muscle mass have increased caloric and protein requirements. For this reason, they use different strategies such as whey protein isolate supplementation and/or branched-chain amino acids after sustained training on the premise that they promote an increase in muscle protein synthesis, and therefore an increase in lean mass. OBJECTIVE: To compare body composition changes in physically active people exposed to a strength training program withwhey protein isolate and/or leucine supplementation for 12 weeks. METHODS: Longitudinal prospective randomized study in a group of 10 physically active males, which were randomly assigned to 3 supplementation groups with whey protein isolate, leucine, or a mixture of both, under the same strength training protocol. Body composition was evaluated in 3 moments: week 0, week 6 and week 12 of the intervention. RESULTS: In the evaluated conditions, no statistically significant changes were observed in the variables of body composition and strength based on the different supplementation protocols: Leucine, protein with leucine and protein. CONCLUSIONS: Compared with the other groups, higher results were observed in lean mass and strength in group using the whey protein isolate supplementation with leucine. It should be noted that due to the size of the sample, the difference was not statistically significant.

Residual gastric volume after 3 h of the ingestion of an oral supplement containing carbohydrates alone or associated with whey protein: a randomized crossover pilot study.

BACKGROUND: New formulas including a nitrogenous source to maltodextrin have been reported as preoperative beverages 2-3 h before anesthesia in the elective procedure. Whey protein is a potential candidate for the composition of this clear oral supplement. This study aimed to investigate the gastric residual volume (GRV) of healthy volunteers 3 h after the ingestion of an oral supplement containing carbohydrates (CHO) alone or combined with whey protein (WP). METHODS: This crossover clinical trial design includes young, healthy male volunteers with normal body mass index. Magnetic resonance imaging (MRI) scan of the upper abdomen to measure the GRV was performed in the participants in three phases: (1) after a fasting period of 8 h; (2) immediately after the ingestion of 200 mL of a clear supplement containing: (2a) 10 g of WP and 54 g of CHO (74% glucose and 26% maltodextrin)-WP + CHO group or (2b) 12.5% maltodextrin (25 g)-CHO group; and (3) after 3 h of the ingestion of both types of supplements. A week interval was programmed between phases 2a and 2b. RESULTS: There was no significant difference (p = 0.91; within-group comparison) of the mean ± SD of the GRV between phase 1 (WP + CHO: 23.45 ± 14.01; CHO: 25.03 ± 15.17 cm3; p = 0.78; between-groups comparison) and phase 3 (WP + CHO: 25.66 ± 9.31; CHO: 23.45 ± 13.58 cm3, p = 0.86; between-groups comparison). The GRV of phase 2 (WP + CHO: 206.43 ± 23; CHO: 203.99 ± 12.18 cm3; p = 0.82; between-groups comparison) was significantly greater (p < 0.01; within-group comparison) than both other two phases. CONCLUSION: The GRV after 3 h of the ingestion of either WP + CHO or CHO oral supplement returns to basal fast condition implying that gastric emptying after this interval of time is significantly completed. TRIAL REGISTRATION: Registered and posted on the ClinicalTrials.gov public website with Identifier: NCT05573854.