Microencapsulation properties of protein isolates from three selected Phaseolus legumes in comparison with soy protein isolate

Effect of the Structural Modification of Plant Proteins as Microencapsulating Agents of Bioactive Compounds from Annatto Seeds (Bixa orellana L.)

This project studied the use of lentil protein (LP) and quinoa protein (QP) in their native and modified states as carrier material in the encapsulation process by the ionic gelation technique of annatto seed extract. Soy protein (SP) was used as a model of carrier material and encapsulated bioactive compounds, respectively. The plant proteins were modified by enzymatic hydrolysis, N acylation, and N-cationization to improve their encapsulating properties. Additionally, the secondary structure, differential scanning calorimetry (DSC), solubility as a function of pH, isoelectric point (pI), molecular weight (MW), the content of free thiol groups (SH), the absorption capacity of water (WHC) and fat (FAC), emulsifier activity (EAI), emulsifier stability (ESI), and gelation temperature (Tg) were assessed on proteins in native and modified states. The results obtained demonstrated that in a native state, LP (80.52% and 63.82%) showed higher encapsulation efficiency than QP (73.63% and 45.77%), both for the hydrophilic dye and for the annatto extract. Structural modifications on proteins improve some functional properties, such as solubility, WHC, FAC, EAI, and ESI. However, enzymatic hydrolysis on the proteins decreased the gels' formation, the annatto extract's encapsulated efficiency, and the hydrophilic dye by the ionic gelation method. On the other hand, the modifications of N-acylation and N-cationization increased but did not generate statistically significant differences (p-value > 0.05) in the encapsulation efficiency of both the annatto extract and the hydrophilic dye compared to those obtained with native proteins. This research contributes to understanding how plant proteins (LP and QP) can be modified to enhance their encapsulating and solubility properties. The better encapsulation of bioactive compounds (like annatto extract) can improve product self-life, potentially benefiting the development of functional ingredients for the food industry.

A comprehensive review of mung bean proteins: Extraction, characterization, biological potential, techno-functional properties, modifications, and applications

The popularity of plant-based proteins has increased, and mung bean protein (MBP) has gained immense attention due to its high yield, nutritional value, and health benefits. MBP is rich in lysine and has a highly digestible indispensable amino acid score. Dry and wet extractions are used to extract MBP flours and concentrates/isolates, respectively. To enhance the quality of commercial MBP flours, further research is needed to refine the purity of MBPs using dry extraction methods. Furthermore, MBP possesses various biological potential and techno-functional properties, but its use in food systems is limited by some poor functionalities, such as solubility. Physical, biological, and chemical technologies have been used to improve the techno-functional properties of MBP, which has expanded its applications in traditional foods and novel fields, such as microencapsulation, three-dimensional printing, meat analogs, and protein-based films. However, study on each modification technique remains inadequate. Future research should prioritize exploring the impact of these modifications on the biological potential of MBP and its internal mechanisms of action. This review aims to provide ideas and references for future research and the development of MBP processing technology.

Exploring the Amino-Acid Composition, Secondary Structure, and Physicochemical and Functional Properties of Chickpea Protein Isolates

This study examined the amino-acid profile, secondary structure, and physicochemical and functional properties of proteins isolated from Anatolian chickpea landraces. Secondary objective of the study was to determine whether a relationship exists between the amino-acid composition and physicochemical and functional properties. Aspartic acid and glutamic acid were the dominant amino acids, while the isolates were deficient in methionine. Secondary structures were determined by Fourier transform infrared spectroscopy, where the β-sheet was shown to be dominant. The denaturation temperature of the isolates was between 87 and 145 °C, and the highest net surface charge (≃28.6 mV) and solubility (∼95.0%) were observed at pH 9.0-10.0. The isolates' water-holding capacity varied between 2.1 and 2.7 g water/g protein, whereas their oil-holding capacity ranged between 3.4 and 4.4 g oil/g protein. Emulsion capacity, emulsifying activity, and the stability indices of isolates were found to be between 401.2 and 469.1 g oil/g protein, 14.5 and 25.7 m²/g, and 45.7 and 146.9 min, respectively. Isolates of Hisar and Erzincan chickpeas exhibited good emulsifying properties. The Yasa isolate had a relatively high hydrophobic amino-acid content and delivered the best gelation performance. Overall, significant differences in the characteristics of proteins were observed among the different chickpea landraces studied.

Escalate protein plates from legumes for sustainable human nutrition

Protein is one of the most important, foremost, and versatile nutrients in food. The quantity and quality of protein are determinants of its nutritional values. Therefore, adequate consumption of high-quality protein is essential for optimal growth, development, and health of humans. Based on short-term nitrogen balance studies, the Recommended Dietary Allowance of protein for the healthy adult with minimal physical activity is 0.8 g protein/kg body weight (BW) per day. Proteins are present in good quantities in not only animals but also in plants, especially in legumes. With the growing demand for protein, interest in plant proteins is also rising due to their comparative low cost as well as the increase in consumers' demand originating from health and environmental concerns. Legumes are nutrient-dense foods, comprising components identified as "antinutritional factors" that can reduce the bioavailability of macro and micronutrients. Other than nutritive value, the physiochemical and behavioral properties of proteins during processing plays a significant role in determining the end quality of food. The term "complete protein" refers to when all nine essential amino acids are present in the correct proportion in our bodies. To have a balanced diet, the right percentage of protein is required for our body. The consumption of these high protein-containing foods will lead to protein sustainability and eradicate malnutrition. Here, we shed light on major opportunities to strengthen the contribution of diversity in legume crops products to sustainable diets. This review will boost awareness and knowledge on underutilized proteinous foods into national nutritional security programs.

Microcapsules Consisting of Whey Proteins-Coated Droplets of Lipids Embedded in Wall Matrices of Spray-Dried Microcapsules Consisting Mainly of Non-Fat Milk Solids

The effects of wall composition and heat treatment on the formation and properties of core-in-wall emulsions (CIWEs) consisting of whey protein-coated milkfat (AMF) droplets and a dispersion of non-fat milk solids (MSNF) were investigated. Microcapsules were prepared by spray drying these CIWEs. The d_3.2 of the CIWEs ranged from 0.36 to 0.54 μm. Surface excess of the CIWEs ranged from 1.39 to 6.57 mg/m², and was influenced by concentration of whey proteins and heat treatment (30 min at 90 °C). Results indicated a preferential adsorption of β-lg at the O/W interface. Whey proteins accounted for up to 90% of the proteins adsorbed at the O/W interface. The core retention during spray drying ranged from 90.3% to 97.6% and microencapsulation efficiency ranged from 77.9% to 93.3%. The microcapsules exhibited an excellent long-term oxidative stability at 20 and 30 °C that was superior to that of microcapsules consisting of milkfat and MSNF, where the O/W interface was populated mainly by caseins. The superior oxidative stability could be attributed to the formation of dense whey-proteins-based films at the O/W interfaces of the CIWEs that isolated the core domains from the environment. The results open new opportunities in developing highly stable lipids-containing microcapsules and dairy powders.

Proteins from leguminous plants: from structure, property to the function in encapsulation/binding and delivery of bioactive compounds

Leguminous proteins are important nutritional components in leguminous plants, and they have different structures and functions depending on their sources. Due to their specific structures and physicochemical properties, leguminous proteins have received much attention in food and nutritional applications, and they can be applied as various carriers for binding/encapsulation and delivery of food bioactive compounds. In this review, we systematically summarize the different structures and functional properties of several leguminous proteins which can be classified as ferritin, trypsin inhibitor, β-conglycinin, glycinin, and various leguminous proteins isolates. Moreover, we review the development of leguminous proteins as carriers of food bioactive compounds, and emphasize the functions of leguminous protein-based binding/encapsulation and delivery in overcoming the low bioavailability, instability and low absorption efficiency of food bioactive compounds. The limitations and challenges of the utilization of leguminous proteins as carriers of food bioactive compounds are also discussed. Possible approaches to resolve the limitations of applying leguminous proteins such as instability of proteins and poor absorption of bioactive compounds are recommended.

Use of Plant Proteins as Microencapsulating Agents of Bioactive Compounds Extracted from Annatto Seeds (Bixa orellana L.)

This study aimed to assess the thermal stability of the bioactive compounds from annatto seed extract, encapsulated by ionic gelation using quinoa proteins, lentil proteins, soy proteins, and sodium caseinate as carrying materials. The 10.0% aqueous dispersions of the different proteins (carriers) were prepared and mixed with the annatto seed extract. The dispersions were then extruded into a calcium chloride solution to induce the extract encapsulation. The capsules were characterized by encapsulation efficiency, particle size, infrared transmission spectroscopy, confocal microscopy, and scanning electron microscopy (SEM). The antioxidant and antimicrobial activities, the polyphenol compounds, and bixin content from the free and encapsulated extract were assessed once stored for 12 d at different temperatures (4 °C, 25 °C, and 65 °C). The results demonstrated the ability of the proteins to encapsulate the annatto extract with encapsulation efficiencies ranging from 58% to 80%, where the protein structure and amino acid content were the relevant factors to obtain high encapsulation efficiencies. The free extracts stored at 65 °C for 12 d experienced a degradation of bixin and polyphenol compounds, respectively. Conversely, the encapsulated extract had degradations from ~34.00% to ~4.05% for polyphenol compounds and ~20.0% for bixin, respectively. These proteins have a potential encapsulation capacity of annatto extract by ionic gelation.

State-of-the-Art Production Chains for Peas, Beans and Chickpeas-Valorization of Agro-Industrial Residues and Applications of Derived Extracts

The world is confronted with the depletion of natural resources due to their unsustainable use and the increasing size of populations. In this context, the efficient use of by-products, residues and wastes generated from agro-industrial and food processing opens the perspective for a wide range of benefits. In particular, legume residues are produced yearly in very large amounts and may represent an interesting source of plant proteins that contribute to satisfying the steadily increasing global protein demand. Innovative biorefinery extraction cascades may also enable the recovery of further bioactive molecules and fibers from these insufficiently tapped biomass streams. This review article gives a summary of the potential for the valorization of legume residual streams resulting from agro-industrial processing and more particularly for pea, green bean and chickpea by-products/wastes. Valuable information on the annual production volumes, geographical origin and state-of-the-art technologies for the extraction of proteins, fibers and other bioactive molecules from this source of biomass, is exhaustively listed and discussed. Finally, promising applications, already using the recovered fractions from pea, bean and chickpea residues for the formulation of feed, food, cosmetic and packaging products, are listed and discussed.

Formation and Stability of Pea Proteins Nanoparticles Using Ethanol-Induced Desolvation

Protein nanoparticles have recently found a lot of interests due to their unique physicochemical properties and structure-functionality compared to the conventional proteins. The aim of this research was to synthesize pea protein nanoparticles (PPN) using ethanol-induced desolvation, to determine the changes in secondary structures and the particle stability in an aqueous dispersion. The nanoparticles were prepared by diluting 3.0 wt% pea protein solutions in 1-5 times ethanol at pH 3 and 10 at different temperatures. Higher ratios of ethanol caused greater extent of desolvation and larger sizes of PPN. After homogenization at 5000 psi for 5 min, PPN displayed uniform size distribution with a smaller size and higher zeta potential at pH 10 compared to pH 3. PPN prepared from a preliminary thermal treatment at 95 °C revealed a smaller size than those synthesized at 25 °C. Electron microscopy showed roughly spherical shape and extensively aggregated state of the nanoparticles. Addition of ethanol caused a reduction in β-sheets and an increase in α-helices and random coil structures of the proteins. When PPN were separated from ethanol and re-dispersed in deionized water (pH 7), they were stable over four weeks, although some solubilization of proteins leading to a loss in particle size was observed.

Microencapsulation of a Model Oil in Wall System Consisting of Wheat Proteins Isolate (WHPI) and Lactose

Microencapsulation allows for the entrapment, protection, and delivery of sensitive and/or active desired nutrients and ingredients as well as biologically-active agents. The microencapsulating properties of wall solutions (WS) containing 2.5–10% (w/w) wheat proteins isolate (WHPI) and 17.5–10% (w/w) lactose were investigated. Core-in-wall-emulsions (CIWEs) consisting of the WS and soy oil were prepared at a wall-to-core (W:C) ratio ranging from 25:75 to 75:25 (w/w). Microcapsules were prepared by spray-drying the CIWEs. The CIWEs had a mean particle diameter smaller than 0.5 µm and surface excess that ranged from 1.59 to 5.32 mg/m2. In all cases, microcapsules with smooth outer surfaces that exhibited only limited surface indentation were obtained. The core, in the form of protein-coated lipid droplets, was embedded throughout the wall matrices. In all but one case, core retention was higher than 83%, and in 50% of the cases, it was higher than 90%. Core retention was significantly influenced the composition of the WS and by W:C ratio (p < 0.05). Except for two cases, microcapsules exhibited very limited core extractability. The microencapsulation efficiency was >90% and was influenced, to a certain degree, by the composition of the CIWEs. Results indicated the potential for utilizing wall systems consisting of WHPI and lactose as effective and highly functional microencapsulating agents in food and related applications.

Soy Protein Microparticles for Enhanced Oral Ibuprofen Delivery: Preparation, Characterization, and In Vitro Release Evaluation

The objective of this work was to evaluate soy protein isolate (SPI) and acylated soy protein (SPA) as spray-drying encapsulation carriers for oral pharmaceutical applications. SPI acylation was performed by the Schotten-Baumann reaction. SPA, with an acylation rate of 41%, displayed a decrease in solubility in acidic conditions, whereas its solubility was unaffected by basic conditions. The drug encapsulation capacities of both SPI and SPA were tested with ibuprofen (IBU) as a model poorly soluble drug. IBU-SPI and IBU-SPA particles were obtained by spray-drying under eco-friendly conditions. Yields of 70 to 87% and microencapsulation efficiencies exceeding 80% were attained for an IBU content of 20 to 40% w/w, confirming the excellent microencapsulation properties of SPI and the suitability of the chemical modification. The in vitro release kinetics of IBU were studied in simulated gastrointestinal conditions (pH 1.2 and pH 6.8, 37°C). pH-sensitive release patterns were observed, with an optimized low rate of release in simulated gastric fluid for SPA formulations, and a rapid and complete release in simulated intestinal fluid for both formulations, due to the optimal pattern of pH-dependent solubility for SPA and the molecular dispersion of IBU in soy protein. These results demonstrate that SPI and SPA are relevant for the development of pH-sensitive drug delivery systems for the oral route.