Improved Protein Digestibility Research Articles

Effect of Conventional and Microwave Heating on Protein and Odor Profile in Soymilk Powder

Soymilk contained serine protease enzymes with inhibitory activity against trypsin, causing a negative effect on nutritional absorption. This project aimed to investigate the effects of conventional heating (100 °C/20 min) and microwave heating (360–900 W/1–6 min) on trypsin inhibitor, protein digestibility, and odor profiles. Soymilk contained 46–47% protein, regardless of heating conditions. Using scanning electron microscopy, it can be seen that the conventionally heated sample had a smooth surface and a porous structure, whereas microwave-heated samples contained a protein matrix in clusters with rough surfaces. The molecular weight of proteins in SDS-PAGE was reduced to 19 kDa and <16 kDa after conventional and microwave heating, respectively, resulting in the reduction of trypsin inhibitor from 36.66 to 0.91 and 0.56–0.66 mg/g, respectively. Protein digestibility was significantly improved when either the conventional heating at 100 °C for 20 min or the microwave heating at 900 W for 6 min was applied. From e-nose analysis, the beany flavor was reduced after the microwave heating for 3–6 min, and the highest intensity of the sweet odor compounds were observed after the microwave heating at 600 W for 1 min. Due to the short processing time, microwave heating was then recommended for inhibition of trypsin inhibitors and improving protein digestibility.

The Effect of Heat Treatment on the Digestion and Absorption Properties of Protein in Sea Cucumber Body Wall.

This study was designed, for the first time, to investigate the effect of oxidation on the digestion and absorption properties of protein in boiled sea cucumber body wall (BSCBW) via simulated digestion combined with everted-rat-gut-sac models. Boiling heat treatments led to protein oxidation in SCBW, manifested by increases in free radical intensity, thiobarbituric acid reactive substances, carbonyl groups, disulfide bonds, dityrosine bonds, advanced glycation end products, protein hydrophobicity and aggregation, and declines in both free sulfhydryl groups and secondary structure transition from α-helix to β-sheet. Boiling for 2 h caused anti-digestion collagen unfolding, provided the action site for protease and improved protein digestion and absorption levels. On the contrary, excessive oxidative modification of 4 h BSCBW resulted in decreased protein digestion and absorption levels. From the perspective of texture, digestion and absorption properties, boiling for 2 h can obtain sea cucumber products with better edible and digestible properties, which is considered to be a better processing condition.

The efficacy of hydrolized feathermeal as a protein source in diets for juvenile catfish Ictalurus punctatus

Chicken feather meal is often viewed as an undesirable product, as most people think of ground up feathers, which have many processing and nutritional issues. However, modern feather meals are produced through a hydrolysis process which greatly improves protein digestibility. Given the poor understanding of the quality of these meals, we chose to evaluate the efficacy of hydrolyzed feather meal (HFM) as a protein source in channel catfish feeds. For this work, we investigated the replacement of either poultry-by-product meal (PBM) or soybean meal (SBM) in a practical feed formulation for juvenile catfish. The basal diet contained 6% PBM and 56.5% SBM. For the first series of diets, we incrementally replaced PBM with 2.5% and 5% hydrolyzed feather meal (HFM). The second series included five experimental diets with SBM replaced by HFM at a rate of 2.5%, 5%, 7.5%, 10%, and 15%. Diets were formulated to be iso‑nitrogenous and essential amino acids were supplemented to maintain minimal levels that met the nutritional requirements. Catfish were stocked at 15 fish per aquaria using four replicates per treatment and grown for 78 days. The survival of the catfish was above 85% across all treatments with no significant differences found due to diet. Apart from one diet, the inclusion of HFM did not influence the growth or FCR of the fish. Diet 3, which contained 5% HFM as a complete replacement for PBM had significantly lower growth and FCR than the other treatments. These results indicate that up to 20% HFM can be used in catfish feeds a as long as there is a low level of another animal protein. However, the complete replacement of PM with HFM was not successful.

Nutritional value in sustainability assessment of protein-rich ingredients and foods: A ‘farm-to-faeces’ approach

The environmental impact of ingredients and foods is often assessed from production of the raw materials up to consumption (‘farm-to-fork’ system boundaries). Comparing animal-to plant-based protein ingredients and foods points to plant proteins as being more sustainable than animal-sourced ingredients. However, the nutritive quality of plant proteins is often less than that of animal proteins, while processing also affects the nutritional value of proteins. Incorporating the protein digestibility as a functional unit into the life cycle assessment, a ‘farm-to-faeces’ approach, provides a more actionable measurement to compare a set of ingredients, processes or final products. Conventionally and mildly fractionated pea protein ingredients were compared to a whey protein isolate acting as a reference of animal-sourced proteins. Processing influences both the digestibility and the overall environmental impact of the food. In some cases, processing might improve protein digestibility while different processes or conditions could reduce it. The digestibility of conventional ingredients such as a protein isolate (pea and whey) is reduced more strongly by processing than the mildly fractionated ingredients. Mild fractions always provide a more environmentally sustainable alternative to whey and pea protein isolates, in relation to both ingredient production and protein digestibility, demonstrating the usefulness of mild processing. In general, this study clearly demonstrates that processing and digestion should be included in a life cycle assessment study, to obtain a correct view of the impact of fulfilling our nutritional needs.

Oral Administration of Animal and Plant Protein Mixture with Lactiplantibacillus plantarum IDCC 3501 Improves Protein Digestibility

A combined usage of animal and plant proteins-mixture could aid to solve environmental and social problems arising from the use of animal protein alone, while also improving the taste and texture of plant protein. Protein mixtures could be a better protein source due to the high availability of amino acids in the body compared with single proteins. Consuming proteins with probiotics can provide more beneficial health effects by helping to hydrolyze protein and absorb amino acids in the body. In this study, coadministration of an animal and plant protein mixture with a high concentration of probiotics was investigated to increase protein digestibility and amino acids absorbability in a mice model. Lactiplantibacillus plantarum IDCC 3501, which has the maximum ability to hydrolyze a protein mixture, composed of soybean protein and milk protein, was selected, and the changes in mice (C57BL/6J, male, six weeks) were investigated after the coadministration of protein mixture and 5 × 108 or 5 × 109 CFU/mL of L. plantarum for eight weeks. Normal diet, high-protein diet (HPD), and HPD supplementing L. plantarum were separately administered to mice. Food and water consumption of the mice did not differ depending on diet type. Measurements of the serum concentrations of amino acids showed that the absorption of aspartate, glutamate, isoleucine, leucine, valine, and lysine increased when high concentrations of protein and probiotics were administered. Thus, high L. plantarum concentrations could be a protein diet supplementation to improve health by promoting the absorption of amino acids.

Guar gum as galactomannan source induces dysbiosis and reduces performance in broiler chickens and dietary β-mannanase restores the gut homeostasis

Galactomannans are abundant nonstarch polysaccharides in broiler feed ingredients. In broilers, diets with high levels of galactomannans have been associated with innate immune response stimulation, poor zootechnical performance, nutrient and lipid absorption, and excessive digesta viscosity. However, data about its effects on the gut microbiome are scarce. β-Mannanases are enzymes that can hydrolyze β-mannans, resulting in better nutrient utilization. In the current study, we have evaluated the effect of guar gum, a source of galactomannans, supplemented to broiler diets, either with or without β-mannanase supplementation, on the microbiota composition, in an attempt to describe the potential role of the intestinal microbiota in β-mannanase-induced gut health and performance improvements. One-day-old broiler chickens (n=756) were randomly divided into 3 treatments: control diet, guar gum-supplemented diet (1.7%), or guar gum-supplemented diet+β-mannanase (Hemicell 330 g/ton). The zootechnical performance, gut morphometry, ileal and cecal microbiome, and short-chain fatty acid concentrations were evaluated at different time points. The guar gum supplementation decreased the zootechnical performance, and the β-mannanase supplementation restored performance to control levels. The mannan-rich diet-induced dysbiosis, with marked effects on the cecal microbiota composition. The guar gum-supplemented diet increased the cecal abundance of the genera Lactobacillus, Roseburia, Clostridium sensu stricto 1, and Escherichia-Shigella, and decreased Intestinimonas, Alistipes, Butyricicoccus, and Faecalibacterium. In general, dietary β-mannanase supplementation restored the main microbial shifts induced by guar gum to levels of the control group. In addition, the β-mannanase supplementation reduced cecal isobutyric, isovaleric, valeric acid, and branched-chain fatty acid concentrations as compared to the guar gum-supplemented diet group, suggesting improved protein digestion and reduced cecal protein fermentation. In conclusion, a galactomannan-rich diet impairs zootechnical performance in broilers and results in a diet-induced dysbiosis. β-Mannanase supplementation restored the gut microbiota composition and zootechnical performance to control levels.

Phytase Enzyme Improves Growth Performance and Body Chemical Composition of Sangkuriang Catfish (Clarias gariepinus var. Sangkuriang) Juvenile

Due to their nutritional value, alternative vegetable materials such as soybean are needed to promote sustainable aquaculture development. However, phytate in soybean could interfere with the protein digestion of the fish body. This study examines the effectiveness of phytate enzymes in enhancing protein digestibility, growth performance, mineral digestion, and body chemical composition of Sangkuriang catfish (Clarias gariepinus var. Sangkuriang) juveniles. The study was completely randomized design with 4 treatments and 3 repetitions. One hundred thirteen Sangkuriang catfish juveniles (7.65 ± 0.14 g) were used for each repetition. The fish were fed with an experimental diet supplemented with various doses of phytase enzyme: 0 (A), 500 (B), 1,000 (C), and 1,500 (D) FTU/kg of feed. The mineral digestibility, protein digestibility, protein efficiency ratio (PER), feed conversion ratio (FCR), the efficiency of feed utilization (EFU), apparent digestibility coefficients (ADCp), relative growth rate (RGR), and survival rate (SR) were observed. Data were analyzed using analysis of variance followed by Duncan’s multiple range test. The results showed that adding 1,000 FTU/kg of phytase enzyme (C) exhibited the highest PER, FCR, EFU, ADCp, and RGR value of Sangkuriang catfish juveniles compared to other treatments. All treatment groups (B-C) had the same SR value (100%) and had the highest crude protein and ash content compared to the A group. All group treatments also exhibited a higher phosphorus, calcium, potassium, magnesium, iron, zinc, manganese, copper, and cobalt. Therefore, phytase enzyme supplementation could improve protein digestibility, mineral digestibility, growth performance, and body chemical composition of Sangkuriang catfish juveniles.

Combination of three null mutations affecting seed protein accumulation in pea (Pisum sativum L.) impacts positively on digestibility

The presence of so-called anti-nutritional factors can reduce the bioavailability of nutrients following consumption of seeds which are otherwise an excellent source of proteins, carbohydrates and micronutrients. Among the proteins associated with negative effects on quality in pea (Pisum sativum L.) seeds are lectin, pea albumin 2 (PA2) and trypsin inhibitors (TI). Here we have investigated the impact of these proteins on protein digestibility and amino acid availability, using naturally occurring and derived mutant lines of pea lacking these proteins. The mutations were stacked to generate a triple mutant which was compared with a wild-type progenitor and a line lacking the major seed trypsin inhibitors alone. In vitro digestions following the INFOGEST protocol revealed significant differences in the degree of hydrolysis, protein profile and apparent amino acid availability among the pea variants. Proteins resistant to digestion were identified by MALDI-TOF mass spectrometry and amino acid profiles of digested samples determined. The results indicate that pea seeds lacking certain proteins can be used in the development of novel foods which have improved protein digestibility, and without negative impact on seed protein concentration or yield.

Fermented food products for gastrointestinal health and related diseases

The incidence of lifestyle diseases such as inflammatory bowel diseases is increasing due to unhealthy eating habits and modern lifestyles, resulting in a growing demand for fermented foods worldwide due to their scientifically proven functional and nutritional attributes. Fermented foods are obtained by controlled microbial growth and enzymatic degradation of food constituents. These foods have a good amount of probiotic bacteria and bioactive peptides that benefit human health. Bioactive peptides are formed by either fermentation or enzymatic hydrolysis of food proteins. Fermented foods and beverages i.e., dahi, yogurt, kefir, kimchi, sourdough bread, pickles play a significant role in gut microbiota balance and mental health. Starter culture used in the fermentation of food products provide various health-promoting activities to fermented foods like anti-oxidant activity, anti-hypertensive activity, probiotic activity and improves protein digestibility. Several groups of lactic acid bacteria (LAB) strains produce Exopolysaccharides (EPS) such as  and - glucans, galactans, fructans, and gluco- and fructo-oligosaccharides. EPS produced by LAB has a positive impact on gut health. In addition, probiotic bacteria have proven to be a beneficial ingredient for any gut disorder (inside or outside the GI tract). They regulate the level of immunoglobulins (IgA) and inflammatory cytokines and improve gut barrier activity. Symbiotic yogurt (made with bacterial strains of Lactobacillus acidophilus and Bifidobacterium longum) helps raise high-density lipoprotein (HDL) cholesterol and also changes the ratio of low-density lipoprotein (LDL) to HDL. Consumption of kefir inhibits the pathogen's action by the production of acids and bacteriocins. Isolation and pharmaceutical applications of health-promoting bioactive peptides from fermented foods have been emerging in dairy and food research areas.

Impact of Spontaneous Fermentation and Inoculum with Natural Whey Starter on Peptidomic Profile and Biological Activities of Cheese Whey: A Comparative Study

Fermentation is a promising solution to valorize cheese whey, the main by-product of the dairy industry. In Parmigiano Reggiano cheese production, natural whey starter (NWS), an undefined community of thermophilic lactic acid bacteria, is obtained from the previous day residual whey through incubation at gradually decreasing temperature after curd cooking. The aim of this study was to investigate the effect of fermentation regime (spontaneous (S) and NWS-inoculated (I-NWS)) on biofunctionalities and release of bioactive peptides during whey fermentation. In S and I-NWS trials proteolysis reached a peak after 24 h, which corresponded to the drop out in pH and the maximum increase in lactic acid. Biological activities increased as a function of fermentation time. NWS inoculum positively affected antioxidant activity, whilst S overcame I-NWS in angiotensin-converting enzyme (ACE) and DPP-IV (dipeptidyl peptidase IV) inhibitory activities. Peptidomics revealed more than 400 peptides, mainly derived from β-casein, κ-casein, and α-lactalbumin. Among them, 49 were bioactive and 21 were ACE-inhibitors. Semi-quantitative analysis strongly correlated ACE-inhibitory activity with the sum of the peptide abundance of ACE-inhibitory peptides. In both samples, lactotripeptide isoleucine-proline-proline (IPP) was higher than valine-proline-proline (VPP), with the highest content in S after 24 h of fermentation. In conclusion, we demonstrated the ability of whey endogenous microbiota and NWS to extensively hydrolyze whey proteins, promoting the release of bioactive peptides and improving protein digestibility.

Protein blends and extrusion processing to improve the nutritional quality of plant proteins.

Plant proteins have low protein nutritional quality due to their unbalanced indispensable amino acid (IAA) profile and the presence of antinutritional factors (ANFs) that limit protein digestibility. The blending of pulses with cereals/pseudocereals can ensure a complete protein source of IAA. In addition, extrusion may be an effective way to reduce ANFs and improve protein digestibility. Thereby, we aimed to improve the protein nutritional quality of plant protein ingredients by blending different protein sources and applying extrusion processing. Protein blends were prepared with pea, faba bean, quinoa, hemp, and/or oat concentrates or flours, and extrudates were prepared either rich in pulses (texturized vegetable proteins, TVPs) or rich in cereals (referred to here as Snacks). After extrusion, all samples showed a reduction in trypsin inhibitor activity (TIA) greater than 71%. Extrusion caused an increase in the total in vitro protein digestibility (IVPD) of TVPs, whereas no significant effect was shown for the snacks. According to the molecular weight distribution, TVPs presented protein aggregation. The results suggest that the positive effect of decreased TIA on IVPD is partially counteracted by the formation of aggregates during extrusion which restricts enzyme accessibility. After extrusion, all snacks retained a balanced amino acid score whereas a small loss of methionine + cysteine was observed in the TVPs, resulting in a small reduction in IAA content. Thus, extrusion has the potential to improve the nutritional quality of TVPs by reducing TIA and increasing protein digestibility.

Methods for improving meat protein digestibility in older adults

This review explores the factors that improve meat protein digestibility and applies the findings to the development of home meal replacements with improved protein digestion rates in older adults. Various methods improve the digestion rate of proteins, such as heat, ultrasound, high pressure, or pulse electric field. In addition, probiotics aid in protein digestion by improving the function of digestive organs and secreting enzymes. Plant-derived proteases, such as papain, bromelain, ficin, actinidin, or zingibain, can also improve the protein digestion rate; however, the digestion rate is dependent on the plant enzyme used and protein characteristics. Sous vide processing improves the rate and extent of protein digestibility, but the protein digestion rate decreases with increasing temperature and heating time. Ultrasound, high pressure, or pulsed electric field treatments degrade the protein structure and increase the proteolytic enzyme contact area to improve the protein digestion rate.

Solid-state fermentation alters the fate of red kidney bean protein during buccal and gastrointestinal digestion: Relationship with cotyledon cell wall integrity

The relationship between legume cotyledon cell wall and macromolecular nutrient digestibility has attracted increased attention. In this study, the effect of solid-state fermentation by Rhizopus oligosporus RT-3 on the digestibility of red kidney bean protein and its relationship with cotyledon cell integrity were investigated. Buccal digestion and gastrointestinal digestion were performed to compare the fate of protein between unfermented (F0) and fermented samples. Results showed a remarkable disruption in cotyledon cell integrity at the late fermentation period, and it was accompanied by a possible migration/degradation of protein matrix. Buccal and gastrointestinal digestion barely affected cell wall integrity at F0 but notably disintegrated cell morphology at 29 h of fermentation (F29). As this fermentation time, gastrointestinal digestion resulted in higher contents of soluble proteins, peptides, and free amino acids by 1.4-, 1.8-, and 2.5-fold, respectively. Therefore, solid-state fermentation facilitated the structural breakdown of cotyledon cell walls, thereby further improving protein digestibility.

Physicochemical properties, texture, and in vitro protein digestibility in high-moisture extrudate with different oil/water ratio

Oil addition is challenging during high-moisture extrusion due to the negative fiber formation effects. A previous study found that oil-in-water (O/W) emulsions could significantly increase the oil content in high-moisture extrudates, but the molecular mechanism remained unclear. This study aimed to determine O/W emulsion influence on protein physicochemical properties in SPI extrudates during high-moisture extrusion. O/W emulsions were mixed with soy protein isolates (SPI) to prepare extrudates with oil/water ratios of 0/65, 4/61, and 8/57 (w/w). SDS-PAGE and ATR-FTIR analysis showed that higher oil/water ratios enhanced protein aggregation and promoted alteration from β-sheet to random coil in SPI extrudates, which could be correlated to the reduction of protein solubility. The color was altered to lighter and yellow, and hardness, chewiness, and fiber degree decreased with increased oil/water ratios in SPI extrudates. In addition, in vitro digestion analyses showed that higher oil content contributed to improved protein digestibility.

243 Nutritional Intervention for Reduced Nitrogen Excretion and Better Intestinal Health

Abstract Increased awareness on public welfare has augmented the demand for more sustainable swine production. Nutritional interventions have been done to improve the dietary nitrogen utilization in order to reduce nitrogen excretion and enhance the intestinal health of pigs. Highly digestible protein supplements have been used as a strategy to enhance intestinal health and nitrogen utilization. Taking advantage of crystalline amino acids, low CP formulation with adequate amino acid supplementation has been used to reduce feed cost and improve intestinal health by decreasing protein fermentation. It has been estimated that reducing 1% protein in the diet reduces 9% nitrogen excretion and, consequently, environmental pollution. Feeding functional feed additives is another strategy to enhance intestinal health and nutrient digestion. Selected feed enzymes can reduce nitrogen excretion and improve intestinal health by directly increasing the digestibility of protein or by reducing antinutritional compounds such as allergenic proteins, phytate, and NSP that can impair protein digestion. Selected organic acids have antimicrobial properties and used in animal feeds to modulate intestinal microbiota, to enhance intestinal epithelial barrier function, and to improve protein digestibility. Selected prebiotics, probiotics, and postbiotics can reduce nitrogen excretion by changing the intestinal environment, enhancing the intestinal morphology, immune status, and the microbiota composition. Enhanced intestinal health with increased beneficial microbiota would increase the efficiency of nitrogen utilization consequently reducing nitrogen excretion. In summary, different nutritional strategies can be adopted to improve growth efficiency related to enhanced intestinal health and nutrient utilization, consequently reducing nitrogen excretion. Finally, improved feed efficiency and reduced nutrient waste would assure sustainable swine production, economic incentives to producers, and public welfare.

Preparation, characterization and bioavailability studies of Tegillarca granosa hemoglobin and its glycosylated products

Iron deficiency anemia (IDA) is a common micronutrient deficiency. Tegillarca granosa (T. granosa) is a good source of iron due to its high content of hemoglobin. The present study aimed to determine the effects of glycosylation on structure, physicochemical characteristics and iron bioavailability of hemoglobin. Using Box-Behnken design and response surface methodology, the optimal conditions for hemoglobin-chitosan glycosylation were obtained: 61.8 °C, pH 6.3, hemoglobin/chitosan mass ratio of 4.3 and reaction time of 15 min. The formation of hemoglobin-chitosan conjugates was verified by SDS-PAGE and fluorescence spectroscopy. The surface hydrophobicity of hemoglobin was reduced by 20.90–65.05 % after glycosylation, along with the observations of elevated water-holding capacity, likely owing to the introduction of hydrophilic groups. Antioxidant capacity of glycosylated products (0.41–0.66 μM Trolox/mg protein) was markedly greater than that of original protein (0.06 μM Trolox/mg protein) due to the formation of brown polymers with antioxidant activity. In addition, glycosylation improved in vitro digestibility of hemoglobin by 41.15–69.09 %, which could be attributed to less β-sheet in secondary structures. Moreover, hemoglobin (324.38 ng/mg) exhibited better iron absorption than FeSO4 (121.63 ng/mg), with the value being further enhanced by glycosylation (442.73 ng/mg), which may be due to the improved protein digestibility and iron-chelating capacity.

Impact of protein oxidation induced by different cooking methods in channel fish (Ietalurus punetaus) on structure and in vitro digestion of protein

SummaryThis study was designed to evaluate the effect of different cooking methods on the protein digestion characteristics of channel fish (Ietalurus punetaus). The channel fish muscles were subjected to different cooking methods, namely boiling, steaming and roasting and were subjected to in vitro gastrointestinal digestion simulation using raw fish as a control. All the cooking methods increased the protein digestibility (1.60–8.28%) and decreased the protein particle size at the end of the gastrointestinal digestion. The highest protein digestibility (66.78%) and the smallest protein particle size values (600.7 nm) were observed for the steamed group. Samples which were steam cooked showed lowest β‐sheet content (9.63 ± 0.81%) and were accompanied with moderate protein oxidation. As the core temperature increased from 40°C to 90°C, protein oxidation increased significantly (P < 0.05) with the increase of carbonyl groups and Schiff bases and decrease of sulfhydryl groups in all cooked groups. Based on the results, steaming was recommended as the best methods of cooking channel fish for improved protein digestibility.

Estimating genetic variability among diverse lentil collections through novel multivariate techniques.

Lentil is an important food legume throughout the world and Pakistan stands at 18th position with 8,610 tons production from 17,457 hectares. It is rich in protein, carbohydrates, fat, fiber, and minerals that can potentially meet food security and malnutrition issues, particularly in South Asia. Two hundred and twenty lentil genotypes representing Pakistan (178), Syria (14), and the USA (22) including 6 from unknown origins were studied for yield, yield contributing traits, and cooking time (CT). Genotype 6122 (Pakistan) performed the best during both years with seed yield per plant (SY) 68±1.7 g, biological yield per plant (BY) 264±2.8 g, pod size (PS) 0.61±0.01 cm, number of seeds per pod (NSP) 2, cooking time (CT) 11 minutes, with no hard seed (HS). The genotypes 6122 (Pakistan) and 6042 (Syria) produced the highest BY, hence these have the potential to be an efficient source of fodder, particularly during extreme winter months. The genotypes 5698 (Pakistan) and 6015 (USA) were late in maturity during 2018-19 while 24783 and 5561 matured early in 2019. A minimum CT of 10 minutes was taken by the genotypes 6074 and 5745 of Pakistani origin. The lowest CT saves energy, time, and resources, keeps flavor, texture, and improves protein digestibility, hence the genotypes with minimum CT are recommended for developing better lentil cultivars. Pearson correlation matrix revealed significant association among several traits, especially SY with BY, PS, and NSP which suggests their use for the future crop improvement program. The PCA revealed a considerable reduction in components for the selection of suitable genotypes with desired traits that could be utilized for future lentil breeding. Structural Equational Model (SEM) for SY based on covariance studies indicated the perfect relationship among variables. Further, hierarchical cluster analysis establishes four clusters for 2017-18, whereas seven clusters for 2018-19. Cluster 4 of 2017-18 and cluster 5 of 2018-19 exhibited the genotypes with the best performance for most of the traits (SY, BY, PS, NSP, CT, and HS). Based on heritability; HSW, SY, BY, NSP were highly heritable, hence these traits are expected for selecting genotypes with genes of interest and for future lentil cultivars. In conclusion, 10 genotypes (5664, 5687, 6084, 6062, 6122, 6058, 6087, 5689, 6042 and 6074) have been suggested to evaluate under multi-location environments for selection of the best one/s or could be utilized in hybridization in future lentil breeding programs.

In vitro digestion of a mixed gel of pork muscle and resistant starch: Salt-soluble protein perspective

The in vitro digestion of a mixed gel (MS) of pork muscle and resistant starch (RS) was investigated and the role of the salt-soluble protein (SSP) in the function promotion of the mixed gel was clarified. The results showed that the mixed muscle gel (MS) and the addition of RS to muscle gel (M + S) presented an improved protein digestion, as indicated by a reduced particle size of the hydrolysates, more degradation of proteins with large molecular weight and more generation of free amino acids compared with the RS-free muscle gel (M). Meanwhile, the hydrolysates of the M + S and MS showed intensified DPPH radical scavenging activities. Specifically, the MS exerted preferable properties in protein digestion and antioxidant activity. Similar digestion characteristics were noticed in mixed SSP gels.The current study revealed that the reinforced functionality of the mixed muscle gel was associated with the binding relationships between SSP and RS during cooking.

Effect of Gastric Bypass on Dietary Protein Digestibility and Dietary Nitrogen Sequestration in the Splanchnic Bed in Rats

Abstract Objectives Roux-en-Y Gastric Bypass (RYGB) decreases the stomach size and bypasses a part of the small intestine. RYGB has been often associated with protein malnutrition but in the light of previous studies, this was not ascribed to protein malabsorption. We hypothesized that dietary amino acids are more sequestered by the small intestine mucosa due to adaptative hypertrophy after RYGB. Our study aimed to quantify the sequestration of dietary nitrogen (N) in the small intestine after RYGB at different times of the post-surgery recovery. Methods Diet-induced obese Wistar rats were operated for RYGB. The control group was composed of pair-fed sham-operated rats. One month (RYGB: n = 9, Sham: n = 8) or three months (RYGB: n = 7, Sham: n = 8) after surgery, rats were fed a test meal including 15N-labeled protein. Protein digestibility and dietary N sequestration in the intestine were assessed by determination of 15N recovery in the digesta and gastrointestinal tract (GIT) tissues 6 h after the meal. Results One month after surgery, protein digestibility in Sham and RYGB rats was 94.0 ± 0.8% and 94.2 ± 1.8% (NS), respectively. Digestibility was similar 3 months after surgery, whatever the group. The GIT was hypertrophied in RYGB after 1 month, an effect that disappeared after 3 months. Dietary N sequestration in the splanchnic bed differed depending on the segment. In the stomach wall as well as the duodenum + jejunum mucosa, N retention was lower in RYGB than in Sham at 1 month, this difference being aggravated at 3 months. In contrast, in the ileum mucosa, there was more N in RYGB than in Sham at 1 month (0.48 ± 0.18% vs 0.3 ± 0.09% of ingested N respectively), these values being similar at 3 months. In the caecum, dietary N was higher in RYGB at 1 month compared to Sham but lower in the colon. No differences between groups were observed in these two segments at 3 months. Conclusions RYGB did not improved protein digestibility, in contrast to the findings of our previous study. Our hypothesis of a higher sequestration in the intestinal wall was confirmed in the ileum and colon only, an effect that tended to be attenuated over time. Funding Sources This study was funded by the doctoral school ABIES.