Higher Protein Digestibility Research Articles

Image mapping of biological changes and structure-function relationship during rice grain development via Synchrotron FTIR spectroscopy

The spatial distribution of compositional elements in milky, dough, and mature rice, together with the structure-function relationship was studied using synchrotron-FTIR. The dough stage aleurone and endosperm had high lipid, protein (amide I and II), and hemicellulose. The amylopectin chain length distribution of starch exhibited small differences among developmental stages. Dough starch featured a greater portion of A and B1 chains, implying a more crystalline and high in resistant starch. The protein in milky-to-dough stage aleurone and endosperm had higher contents of α-helixes than β-sheets, resulting in higher protein digestibility and availability. There were high intensities of the glycosidic peaks of hemicellulose and cellulose, pectin, carbohydrates, and β 1–6 glucans in milky-to-dough stages. They corresponded to higher total, insoluble, and soluble dietary fiber contents in milky-to-dough stage than in mature stage. Young-stage rice was found to be more nutritious and could thus be a functional food source.

Improving grindability and bioaccessibility of chicken bone by in situ steam explosion

SummaryThe impacts of in situ steam explosion (ISE) on the particle size, protein solubility and digestibility, calcium release and structural characteristics of chicken bone powder were analysed. ISE significantly reduced the average particle size from 142.62 to 84.47–105.10 μm, while maintained the proximate compositions. The Fourier transforms infrared spectra and X‐ray diffraction further illustrated that there were no marked differences in the functional groups between native and ISE bone powders. Moreover, soluble protein content in chicken bone powder was remarkably enhanced by the ISE from 3.28 to 3.73 mg g−1. ISE powder (at 121 °C for 90 min) had higher protein digestibility (48.63%) than that of native (30.82%). Finally, ISE powder showed a higher calcium release and 2,2′‐azino‐bis (3‐ethylbenzothiazoline‐6‐sulphonic acid) diammonium salt (ABTS) radical scavenging activity of digestive juice. The results proposed the feasibility of using ISE as an effective strategy to improve the nutritional quality of chicken bone.

Impact of emerging food processing technologies on structural and functional modification of proteins in plant-based meat alternatives: An updated review.

In the past decade, the plant-based meat alternative industry has grown rapidly due to consumers' demand for environmental-friendly, nutritious, sustainable and humane choices. Consumers are not only concerned about the positive relationship between food consumption and health, they are also keen on the environmental sustainability. With such increased consumers' demand for meat alternatives, there is an urgent need for identification and modification of protein sources to imitate the functionality, textural, organoleptic and nutritional characteristics of traditional meat products. However, the plant proteins are not readily digestible and require more functionalization and modification are required. Proteins has to be modified to achieve high quality attributes such as solubility, gelling, emulsifying and foaming properties to make them more palatable and digestible. The protein source from the plant source in order to achieve the claims which needs more high protein digestibility and amino acid bioavailability. In order to achieve these newer emerging non-thermal technologies which can operate under mild temperature conditions can reach a balance between feasibility and reduced environmental impact maintaining the nutritional attributes and functional attributes of the proteins. This review article has discussed the mechanism of protein modification and advancements in the application of non-thermal technologies such as high pressure processing and pulsed electric field and emerging oxidation technologies (ultrasound, cold plasma, and ozone) on the structural modification of plant-based meat alternatives to improve, the techno-functional properties and palatability for successful food product development applications.

Associating Compositional, Nutritional and Techno-Functional Characteristics of Faba Bean (Vicia faba L.) Protein Isolates and Their Production Side-Streams with Potential Food Applications.

Faba beans (Vicia faba L.) show exciting prospects as a sustainable source of protein and fibre, with the potential to transition to a more sustainable food production. This study reveals the compositional, nutritional and techno-functional characteristics of two protein isolates from faba beans (Vicia faba L.), a high-starch fraction and a high-fibre side-stream. During the analysis of those four ingredients, particular attention was paid to the isolates' protein profile and the side-streams' carbohydrate composition. The isoelectric precipitated protein isolate 1 showed a protein content of 72.64 ± 0.31% DM. It exhibited low solubility but superior digestibility and high foam stability. High foaming capacity and low protein digestibility were observed for protein isolate 2, with a protein content of 71.37 ± 0.93% DM. This fraction was highly soluble and consisted primarily of low molecular weight proteins. The high-starch fraction contained 83.87 ± 3.07% DM starch, of which about 66% was resistant starch. Over 65% of the high-fibre fraction was insoluble dietary fibre. The findings of this study provide a detailed understanding of different production fractions of faba beans, which is of great value for future product development.

PROTEIN CONTENT AND COLOR OF GREEN MACROALGAE Ulva lactuca (L.) ON SOAKING TIME AND DRYING METHOD

<p>The green macroalgae <em>Ulva lactuca</em> (L.) is a potential alternative protein source. This study investigates the effect of soaking and different drying methods on the protein and color quality of <em>U. lactuca</em>. Moisture and ash content, color, and protein content, i.e., crude protein, in vitro protein digestibility, and protein solubility of the seaweed were determined. In its conduct, fresh <em>U. lactuca</em> was soaked in fresh water for various soaking times (0, 1, 2, and 3 h). Soaking <em>U. lactuca</em> with the highest protein digestibility was selected for further drying method investigation, i.e., sun-drying, shade-drying, and oven-drying at 40°C. The results reveal that soaking treatment did not affect protein quality significantly, but there was a significant effect of soaking treatment on the ash content and color quality of <em>U. lactuca</em>. Among the drying method, sun drying and oven drying resulted in higher in-vitro protein digestibility and protein solubility compared to shade drying. </p>

Nutritional Evaluation of Milk-, Plant-, and Insect-Based Protein Materials by Protein Digestibility Using the INFOGEST Digestion Method

The INFOGEST method is a valuable tool for understanding and monitoring food digestion as an alternative to in vivo assays. However, few studies have compared animal and alternative protein sources in terms of protein quality using the INFOGEST method. This study aimed to evaluate the protein quality of milk-, plant-, and insect-based protein materials by in vitro protein digestibility and in vitro digestible indispensable amino acid score (DIAAS), following the INFOGEST method. Milk-based protein materials had the highest protein digestibility (86.1-90.8%), followed by soy (85.1%) and wheat (82.3%). These materials had significantly higher protein digestibility compared with zein (65.1%), cricket (63.6%), and mealworm (69.5%). Additionally, the mean values of in vitro DIAAS of milk-based protein materials (105.0-137.5) were higher than those of plant- and insect-based protein materials (1.9-91.0). Milk-based protein materials have higher protein quality than plant- and insect-based protein materials by the nutritional evaluation following the INFOGEST digestion method.

Comparative assessment of grain quality in tannin versus non‐tannin sorghums in the sorghum association panel

AbstractBackground and ObjectivesThe presence of antinutritional compounds such as tannins reduce the nutritional benefits in sorghum. Hence, the major objective was to evaluate the differences in grain quality and physical parameters in 254 tannin and non‐tannin accessions in a diverse set of sorghum association panel.FindingsWide variability was noticed for total protein (11%–19%) and protein digestibility (13%–78%). Tannin content recorded a significant negative relationship (R2 = 0.65, p < .001) with protein digestibility, indicating strong impact of tannins on protein digestibility in sorghum accessions with a pigmented testa. Non‐tannin accessions exhibited higher protein content, protein digestibility, kernel hardness, kernel weight and diameter, and lower phenolics compared to tannin accessions. Among the genetic races, Durra had the highest protein digestibility and Caudatum had the highest kernel weight than other races. In accessions with tannin, red grains had the highest tannin content and lowest protein digestibility than other colored grains.ConclusionsThe study revealed accessions with high protein digestibility of around 71% in both non‐tannin and tannin groups. A tannin containing accession SC1056 had the highest protein digestibility (78%) coupled with high kernel hardness.Significance and NoveltyAccessions with above‐average protein digestibility, either with or without tannins could be ideal donors for breeding for improved grain quality in sorghum.

Small‐scale microwave cooking‐based procedure for evaluation of injera‐making quality of sorghum genotypes

AbstractBackground and ObjectivesEvaluation of the injera‐making quality of sorghum and teff genotypes is problematic because of the large quantity of grain required to make injera using the conventional full‐scale method. This study evaluated a small‐scale microwave cooking‐based injera making procedure. Eight lines expressing waxy and high protein digestibility traits and three normal‐type sorghums were used. Freshly prepared and stored injeras were evaluated using instrumental texture analysis.FindingsThe stress and strain data of fresh and stored injeras from the microwave procedure significantly (p < .01) correlated with those from the full‐scale method: Stress: fresh injera (r = 0.725), 2‐days stored (r = 0.741), 4‐days stored (r = 0.852); Strain: fresh injera (r = 1.000), 2‐days stored (r = 1.000), 4‐days stored (r = 0.999).ConclusionsThe small‐scale microwave procedure uses much less grain and correlates with the full‐scale method.Significance and NoveltyThe small‐scale microwave procedure should enable screening of considerably larger numbers of genotypes for injera‐making quality.

High levels of dietary digestible protein transiently promote beneficial bacteria in adult dog feces

Nowadays, many commercial dog diets select the ingredients not only to meet the needs of the individual and maintain a balance between nutrition/microbiome/health; fiber and protein quality is known to be one of the most important factors in this balance. Diets high in low digestible protein tend to favor microorganisms that when fermenting amino acids generate substances that induce inflammation, while high digestible protein and fermentable fibers have been related to beneficial bacteria. The study's objective was to identify changes in the relative abundance of specific microorganisms (Clostridium perfringens, Enterococcus faecium, Lactobacillus salivarius, Bacteroides fragilis and Fusobacterium varium) by PCR (polymerase chain reaction), associated with two diets of different quality and digestibility. Twenty adult dogs were used, divided into two groups, the first one fed with a high digestibility diet (HD) (n = 10), the second one with a low digestibility diet (LD) (n = 10). After 3 days of adaptation to the diet, fecal samples were taken at days 15 and 30. The results showed that the high-quality diet promotes a transient increase (15 days) in the relative abundance of F. varium and E. faecium, as well as a persistent increase in that of L. salivarius and B. fragilis until day 30. Apparently, however, healthy adult dogs eventually balance their fecal microbiota, regardless of the dietary protein level and digestibility. Therefore, it is difficult to identify clear patterns of the ideal dietary profile in this species.

Advances on the Antioxidant Peptides from Nuts: A Narrow Review.

Antioxidant peptides extracted from natural foods have been studied for their potential use in the development of additives, nutraceuticals, and therapeutic agents. Nut proteins are considered an excellent source of plant-derived proteins for the human diet, due to their high protein content and digestibility of up to 86.22%. Furthermore, compared with grain and soybean proteins, nut proteins have a special amino acid composition, which makes their protein structure different, and promotes their disparate functional characteristics and great bioactivity potential. This review presents the most remarkable studies on antioxidant peptides from nuts, to gain insights into feasible production methods, different evaluation indexes within in vivo or in vitro systems, high bioavailability, and the complex structure-activity relationship resulting from the particularity of their protein structure and amino acid composition. Previously published studies mainly focused on the effects of the production methods/processes of nut-derived peptides on antioxidant activity, and proved that nut-extracted antioxidant peptides can resist the degradation of acid, alkali, and gastrointestinal enzymes, have high antioxidant activity in vitro and in vivo, and also have the potential to cross small intestinal epithelial cells in a stable and integral manner. However, the structure-activity relationship of antioxidant peptides from nuts has not been fully established, and the structure information of antioxidant peptides obtained from various nut protein sources is still unclear. The findings presented in this review can be used to provide the theoretical basis for the design and production of nut-derived antioxidant peptides.

Milling of wheat bran: Influence on digestibility, hydrolysis and nutritional properties of bran protein during in vitro digestion

Wheat bran is a source of high-quality protein with low cost, but the accessibility of bran protein is notably limited by cell wall matrix. This study investigated the effect of milling on the distribution and profile of wheat bran protein, and explored its digestibility, hydrolysis and functional activity during in vitro digestion. It showed that superfine milling effectively released bran protein by disrupting aleurone cells and further improved its solubility and extractability. Superfine wheat bran (19 μm) had higher protein digestibility (53.1 %) and hydrolysis degree (12.7 %) compared to coarse wheat bran (84–1110 μm). Moreover, intestinal digestion promoted the release of free amino acid, mainly arginine (16.4 %), tyrosine (12.8 %) and phenylalanine (9.5 %). Superfine bran protein hydrolysate exhibited the highest antioxidant activity and starch-digestive enzyme inhibitory activity that could facilitate the application of bran as a multifunctional nutrient.

Improving bioaccessibility and physicochemical property of blue-grained wholemeal flour by steam explosion.

Whole grain contains many health-promoting ingredients, but due to its poor bioaccessibility and processibility, it is not widely accepted by consumers. The steam explosion was exploited to modify the nutritional bioaccessibility and the physicochemical properties of wholemeal flour in this study. In vitro starch digestibility, in vitro protein digestibility of wholemeal flour, total flavonoids content, and total phenolics content of digestive juice were used to evaluate the bioaccessibility, and a significant variation (p < 0.05) was noted. Results showed that steam explosion enhanced the gastric protein digestibility ranged from 5.67 to 6.92% and the intestinal protein digestibility ranged from 16.77 to 49.12%. Steam-exploded wholemeal flour (0.5 MPa, 5 min) had the highest protein digestibility and rapidly digestible starch content. Compared with native flour, steam explosion (0.5 MPa, 5 min) contributed to a 0.72-fold and 0.33-fold increment of total flavonoids content and total phenolics content in digestible juice. Chemical changes of wholemeal flour, induced by steam explosion, caused the changes in the solvent retention capacity, rheological property of wholemeal flour, and altered the falling number (and liquefaction number). An increasing tendency to solid-like behavior and the gel strength of wholemeal flour was significantly enhanced by the steam explosion at 0.5 MPa for 5 min, while the gluten was not weakened. This study indicated that steam-exploded wholemeal flour (0.5 MPa, 5 min) could serve as a potential ingredient with the noticeable bioaccessibility and physicochemical properties in cereal products.

Connecting nutritional facts with the traditional ranking of ethnobotanically used fodder grasses by local farmers in Central Punjab of Pakistan

The local farmers of Central Punjab, Pakistan have been using indigenous grasses as vital components of ruminant diets, but little is reported about their nutritional potential. Hence this study investigated nutritive potential of a selection of ethnobotanically important fodder grasses. Multiple nutritional parameters (proximate components, fibre fractions), secondary metabolites (phenolics, tannins) and in vitro digestibility values were determined. Furthermore, the legitimacy of ethnobotanical knowledge of local inhabitants about these grasses was also verified. The results suggested that majority (77%) of these grasses can be regarded as good quality fodders because of their high protein (169 g/kg) and good digestibility (457 g/kg) with moderate fibre (≤ 602 g/kg), lignin (≤ 50 g/kg) and secondary metabolites (total phenols ≤ 87 g/kg, total tannins ≤ 78 g/kg, condensed tannins ≤ 61 g/kg). Pearson correlation between nutritional parameters indicated that in vitro digestibility values were positively correlated with crude proteins (IVDMD, r = + 0.83 and IVOMD, r = + 0.83 respectively) and negatively correlated with fibre (NDF, r = − 0.91), ADF, r = − 0.84 and ADL, r = − 0.82) contents. Moreover, a positive relationship was identified between ethnobotanical knowledge and laboratory findings for studied grasses. Spearman correlation test showed that ranking of grasses based on ethnobotanical preferences were highly correlated (r values) with the laboratory results for CP (0.85), NDF (− 0.76), ADF (− 0.72) and ADL (− 0.62). The resilient complementarities between ethnobotanical preferences and nutritive analysis authenticate farmer’s traditional knowledge, which needed to be aligned with the corresponding scientific data. Farmers can use these findings for appropriate fodder selection and development of precise supplements for feeding ruminants within a sustainable and economically viable livestock industry for food security.

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 &lt; 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.

Mixing of flour mixture components in the production of pasta from nontraditional raw materials

Along with a balanced amino acid composition and high protein digestibility, food products should contain complex carbohydrates and ballast substances (dietary fibers) that ensure the normal functioning of the digestive organs. In this regard, fresh raw foods for dietary pasta are of interest for modern pasta production. It is to such raw materials for the manufacture of dough that flour and starch from some cereals, triticale flour, and stale deformed bread are referred. When forming pasta dough from nontraditional flour raw materials, an important technological value for giving the best rheological properties of the dough is the uniform distribution of the binder component in the mixture – dry wheat gluten (DWG). As an object of experimental research to study the mixing process, a loose flour mixture of cereals (barley, oats, corn, buckwheat, millet, peas, and soybeans) was used, compiled based on calculating the recipe using computer programs. The prepared mixtures are a valuable source of nutrients and minerals. At the same time, to improve the technological properties of the dough as a biologically active additive, 25% DWG is introduced to improve the rheological properties of the dough.

Antioxidant‐enriched gluten‐free bread made with buckwheat flour: Evaluation of technological and nutritional quality

AbstractBackground and ObjectivesBuckwheat is a pseudocereal that has been considered a potential ingredient in bakery products, mainly due to its composition. Many bioactive compounds are found in the outer layers of the grain. This study aimed to produce gluten‐free breads using refined buckwheat flour (RBF) and whole‐grain buckwheat flour (WBF). Three formulations were developed: F1 (100%‐RBF); F2 (70%‐RBF and 30%‐WBF); and F3 (55%‐RBF and 45%‐WBF). The flours were evaluated for pasting, thermal, and thermomechanical properties. The breads were characterized for specific volume, color, moisture content, water activity, firmness, total reducing capacity, antioxidant capacity, rutin and quercetin levels, protein content, in vitro protein digestibility, in vitro starch digestibility, and sensory acceptance.FindingsRBF presented superior results for pasting and thermomechanical properties, with no significant difference for thermal properties. Breads from formulation F1 had greater specific volume, lower firmness, higher protein digestibility, and better sensory acceptance, when compared to F2 and F3. However, the incorporation of WBF to F2 and F3 led to an increase in rutin and quercetin levels, total reducing capacity, antioxidant capacity, and total protein content. Principal components analysis showed a clear distinction between formulations with and without WBF, and how the parameters evaluated were dependent on the composition of the buckwheat flour used for bread preparation.ConclusionsRBF and WBF flours proved to be promising ingredients for the preparation of gluten‐free breads with nutritional improvement.Significance and NoveltyData on the use of WBF and nutritional characteristics of breads were obtained. Future studies should evaluate the presence of antinutritional compounds.

Effect of exogenous protease on growth performance and meat quality in broilers reared on fishmeal-based diets

This study determined the effect of protease supplementation in fishmeal-based diets on growth performance and meat quality of commercial broiler birds. Four hundred and thirty-two (432) day-old broiler chicks were divided into 36 experimental units of 12 chicks each. Nine experimental diets were formulated using three levels (0%, 25%, and 50%) of the fishmeal as protein source, on protein equivalent basis, with or without alkaline protease (CIBENZA® DP100), and with overestimation of nutritional value based on the enhanced digestibility coefficient (EDC) concept because of the use of alkaline protease. Feed consumption and bodyweight were measured weekly. On the last day of the trial, two birds from each pen were picked and processed for carcass and meat quality parameters. Data were analysed by analysis of variance in a 3 x 3 factorial arrangement of completely randomized design. Weight gain and feed conversion ratio (FCR) were improved in the birds with 25% fishmeal as a replacement for soybean meal (SBM) and enzyme supplementation. Similarly, higher protein digestibility, dressing percentage and thigh meat yield were observed in birds fed diets with 25% fishmeal with added enzyme. In the blood biochemical profile, uric acid levels were lower, and cholesterol and triglyceride were higher in the group fed diets with 25% fishmeal with EDC and enzyme. The addition of protease enzyme to the diet with 25% fishmeal improved growth performance, crude protein digestibility and carcass characteristics.

Functionalization of soy residue (okara) by enzymatic hydrolysis and LAB fermentation for B2 bio-enrichment and improved in vitro digestion

The utilization of major edible soy-waste (okara) remains a challenge due to its poor digestion, nutritional imbalance (lack of B-vitamins), and undesirable off-flavors. Herein, fresh okara was enzymatically hydrolyzed and then fermented using the B2-overproducing Lactiplantibacillus plantarum UFG169 strain. SEM micrographs showed the microporous and honeycombed structures on the surface of okara. The off-flavors were reduced, and the essential amino acids content was significantly increased in fermented okara. The higher β-glucosidase activity, increased aglycone isoflavones, and in situ riboflavin (B2) were associated with the enhanced antioxidant potential of the fermented okara. The in vitro digestion of okara resulted in reduced particle size, higher protein digestibility, improved aggregation, lower protein molecular chains, and increased polyphenols. Overall, our study indicated the improved nutrition and digestibility of B2 bio-enriched okara.

Using vitamin C and sodium bentonite as food additives in the diets of common carp Cyprinus carpio L.

An experiments were conducted in open culture system to study the effect of food additives i.e. vitamin C and sodium bentonite to improve the diets characteristics of common carp Cyprinus carpio in concentrations 100, 250 and 500 mg vitamin C/ kg diet and 10, 20 and 30 gm S.B./ kg diet. The results indicate that there was a significant differences (P&lt;0.01) between diets contain additives superior than diets without it (control) the weight increase in fish were 49.03 gm(500 mg vitamin C), 50.79 gm ( S.B. 30 gm) while it was 40 gm in control diets. Also the values of relative growth rates increased (38.35, 40.23 and 31.33 % respectively) and specific growth rats (0.46, 0.48 and 0.39 % wt/day respectively). A distinct effect was noticed of these additives on the food conversion ratio (FCR), protein efficiency ratio (PER) and productive protein value (PPV).While no significant differences (P&gt;0.01) were noticed between diets in food in take which ranged between 2.62 to 3.43 % from body weight .The body protein levels were increased (16.36 – 21.00 %) compared to it level before experiments (15.59) .The diets contain all levels of vit.C and 20 gm of sodium bentonite showed high protein digestibility. The feces weight increased with vit.C level but decreased with sodium bentonite level. It was concluded from the present study that food additives are economically important to increase growth and food efficiency which in turn lowering fish production cost.

A novel sub-pilot-scale direct-contact ultrasonic dehydration technology for sustainable production of distillers dried grains (DDG)

DDG is a major source of protein, calcium, phosphorus, and sulfur is arguably the most important byproduct of the bioethanol industry with increasing demand over the past few years. Reducing energy consumption in the DDG production process and energy recovery from DDG is vital for sustainable bioethanol productions. In this paper, a novel direct-contact multi-frequency, multimode, and modulated (MMM) ultrasonic dryer (US) was developed for the first time and has been applied in dehydration of wet distillers’ grain (WDG). Ultrasonic drying (US) was combined with a convective airflow (HA) at different temperatures of 25 (room temperature), 50 and 70 °C to evaluate the impact of US, HA, and US + HA on drying kinetics, activation energy, chemical compositions, microstructure, and color of DDG. Semi-empirical kinetic models were developed and evaluating drying performances showed that the application of ultrasound significantly enhanced the drying rate and decreased the drying time (by 46%), especially at low drying temperatures. The activation energy for moisture removal in the presence of ultrasound was about 50% of that without ultrasound. The final dried distillers' grains product processed by ultrasonic drying had a brighter color, a higher available protein, a higher digestible protein (the lowest acid detergent insoluble crude protein), and a better surface profile with no compromise on minerals and fiber contents.