Search

Membrane filtration technologies have shown great potential as a gentle and effective method for concentrating and fractionating proteins for food applications. However, the application of this technology to plant-derived protein streams is in its infancy. In this study, an aqueous rapeseed protein concentrate was obtained with wet milling, and its performance during ultrafiltration with two distinct molecular weight cut-offs (10 and 100 kDa) was tested. All rapeseed proteins were retained during filtration. The addition of pectinase during extraction prior to filtration caused important structural modifications to the extract, resulting in increased permeate fluxes, increased carbohydrate permeation and a reduction in irreversible fouling. Lager pore sizes led to more pronounced fouling. FTIR analysis of the spent membranes showed that proteins and lipids are causing irreversible fouling. [ABSTRACT FROM AUTHOR]

旨在揭示弱酸高盐法提取菜籽蛋白的潜力，以脱脂低温压榨菜籽饼为原料，MgCl2溶液为提取液，采用弱酸高盐法提取菜籽蛋白，采用单因素实验研究提取温度、提取pH、提取时间、提取液浓度及料液比对菜籽蛋白提取率的影响，采用正交实验进行菜籽蛋白的弱酸高盐法提取工艺优化，并比较弱酸高盐法菜籽蛋白与碱提酸沉法菜籽蛋白在抗营养因子（植酸、硫苷和单宁）含量与感官特性（气味、色泽）上的差异。结果表明：弱酸高盐法提取菜籽蛋白的最佳工艺条件为提取温度50 ℃、提取pH 6.5、提取时间150 min、提取液浓度150 mmol/L、料液比1∶ 30，在最佳工艺条件下菜籽蛋白提取率为（48.00±1.12）%，纯度为（73.99±2.87）%；弱酸高盐法菜籽蛋白的单宁含量为（0.90±0.06）%，植酸含量为（0.04±0.01）%，未检测出硫苷，色泽为浅黄色，各指标明显优于碱提酸沉法菜籽蛋白。弱酸高盐法作为一种温和的工艺在菜籽蛋白提取方面具有较好的开发潜力和应用前景。To reveal the potential of extracting rapeseed protein by weak acid and high salt method, with defatted low-temperature pressed rapeseed cake as raw material, MgCl2 solution as extracant, the protein was extracted by weak acid and high salt method. The effects of extraction temperature, extraction pH, extraction time, extractant concentration and material-liquid ratio on rapeseed protein extraction rate were studied by single factor experiment, and then orthogonal experiment was conducted to optimize the extraction conditions. The differences of anti-nutritional factors (phytic acid, glucosinolate and tannin)content and sensory characteristics (smell and color) between rapeseed protein extracted by weak acid and high salt method and alkali extraction and acid precipitation method were further studied. The results showed that the optimal conditions for extracting rapeseed protein with weak acid and high salt method were as follows: extraction temperature 50 ℃, extraction pH 6.5, extraction time 150 min, MgCl2 solution concentration 150 mmol/L, and material-liquid ratio 1∶ 30. Under the optimal conditions, the extraction rate of rapeseed protein was (48.00±1.12)%, and the purity was (73.99±287)%. The tannin and phytic acid contents of rapeseed protein obtained by this method were (0.90±006)% and (0.04±0.01)%, respectively, no glucosinolate was detected, and the color was light yellow. Each index was obviously better than that of rapeseed protein prepared by alkali extraction and acid precipitation method. Weak acid and high salt method, as a mild process, has good development potential and application prospect in rapeseed protein extraction.

[Display omitted] Two major protein families are present in rapeseed, namely cruciferins and napins. The structural differences between the two protein families indicate that they might behave differently when their mixture stabilises oil–water interfaces. Therefore, this work focuses on elucidating the role of both proteins in interface and emulsion stabilisation. Protein molecular properties were evaluated, using SEC, DSC, CD, and hydrophobicity analysis. The oil–water interface mechanical properties were studied using LAOS and LAOD. General stress decomposition (GSD) was used as a novel method to characterise the nonlinear response. Additionally, to evaluate the emulsifying properties of the rapeseed proteins, emulsions were prepared using pure napins or cruciferin and also their mixtures at 1:3, 1:1 and 3:1 (w:w) ratios. Cruciferins formed stiff viscoelastic solid-like interfacial layers (G s ′ = 0.046 mN/m; E d ′ = 30.1 mN/m), while napin formed weaker and more stretchable layers at the oil–water interface (G s ′ = 0.010 mN/m; E d ′ = 26.4 mN/m). As a result, cruciferin-formed oil droplets with much higher stability against coalescence (coalescence index, CI up to 10%) than napin-stabilised ones (CI up to 146%) during two months of storage. Both proteins have a different role in emulsions produced with napin-cruciferin mixtures, where cruciferin provides high coalescence stability, while napin induces flocculation. Our work showed the role of each rapeseed protein in liquid–liquid multiphase systems. [ABSTRACT FROM AUTHOR]

Canola is the second-largest cultivated oilseed crop in the world and produces meal consisting of about 35–40% proteins. Despite this, less than 1% of the global plant-based protein market is taken up by canola protein. The reason behind such underutilization of canola protein and its rapeseed counterpart could be the harsh conditions of the industrial oil extraction process, the dark colour of the meal, the presence of various antinutrients, the variability in the protein composition based on the source, and the different properties of the two major protein components. Although academic research has shown immense potential for the use of canola protein and its rapeseed counterpart in emulsion development and stabilization, there is still a vast knowledge gap in efficiently utilizing canola proteins as an effective emulsifier in the development of various emulsion-based foods and beverages. In this context, this review paper summarizes the last 15 years of research on canola and rapeseed proteins as food emulsifiers. It discusses the protein extraction methods, modifications made to improve emulsification, emulsion composition, preparation protocols, and emulsion stability results. The need for further improvement in the scope of the research and reducing the knowledge gap is also highlighted, which could be useful for the food industry to rationally select canola proteins and optimize the processing parameters to obtain products with desirable attributes. [ABSTRACT FROM AUTHOR]

Membrane filtration technologies have shown great potential as a gentle and effective method for concentrating and fractionating proteins for food applications. However, the application of this technology to plant-derived protein streams is in its infancy. In this study, an aqueous rapeseed protein concentrate was obtained with wet milling, and its performance during ultrafiltration with two distinct molecular weight cut-offs (10 and 100 kDa) was tested. All rapeseed proteins were retained during filtration. The addition of pectinase during extraction prior to filtration caused important structural modifications to the extract, resulting in increased permeate fluxes, increased carbohydrate permeation and a reduction in irreversible fouling. Lager pore sizes led to more pronounced fouling. FTIR analysis of the spent membranes showed that proteins and lipids are causing irreversible fouling.

Summary: The binding sites between zinc chelating peptide (ZCP) and zinc have not been clearly understood at the quantum chemistry level. Ala‐Ser‐His (ASH), a new ZCP located in the cruciferin precursor, was identified from in vitro digestion hydrolysate of rapeseed (Brassica napus) protein. Also, ASH exerted the concentration value of 114.09 ± 0.98 mM showing 50% zinc chelating activity. The prepared ASH–Zn (ZCP‐zinc chelate), displayed varying characteristics from ASH on surface microstructures, X‐ray photon energies, and infrared spectrum. The geometric structure of ASH–Zn with minimum free energy was obtained using density functional theory, producing a bridge bond of O21–Zn41–O32 between Ser and His residues. Based on the basic set of 6–311++G (d, p), O21–Zn 41 and O32–Zn41, respectively, had bond lengths of 1.96503 Å and 1.94515 Å, while O21–Zn41–O32 displayed a bond angle of 136.41069°. These findings further promote research on rapeseed proteins providing new possibilities for studying peptide‐metal chelates. [ABSTRACT FROM AUTHOR]

The objective of this study was to extract the rapeseed protein from by-products and further examine the effect of lab-made rapeseed protein on the droplet size, microstructure, colour, encapsulation and apparent viscosity of emulsions. Rapeseed protein-stabilised emulsions with an increasing gradient of milk fat or rapeseed oil (10, 20, 30, 40 and 50%, v/v) were fabricated using a high shear rate homogenisation. All emulsions showed 100% oil encapsulation for 30 days of storage, irrespective of lipid type and the concentration used. Rapeseed oil emulsions were stable against coalescence, whereas the milk fat emulsion showed a partial micro-coalescence. The apparent viscosity of emulsions raised with increased lipid concentrations. Each of the emulsions showed a shear thinning behaviour, a typical behaviour of non-Newtonian fluids. The average droplet size was raised in milk fat and rapeseed oil emulsions when the concentration of lipids increased. A simple approach to manufacturing stable emulsions offers a feasible hint to convert protein-rich by-products into a valuable carrier of saturated or unsaturated lipids for the design of foods with a targeted lipid profile. [ABSTRACT FROM AUTHOR]

Canola is the second-largest cultivated oilseed crop in the world and produces meal consisting of about 35–40% proteins. Despite this, less than 1% of the global plant-based protein market is taken up by canola protein. The reason behind such underutilization of canola protein and its rapeseed counterpart could be the harsh conditions of the industrial oil extraction process, the dark colour of the meal, the presence of various antinutrients, the variability in the protein composition based on the source, and the different properties of the two major protein components. Although academic research has shown immense potential for the use of canola protein and its rapeseed counterpart in emulsion development and stabilization, there is still a vast knowledge gap in efficiently utilizing canola proteins as an effective emulsifier in the development of various emulsion-based foods and beverages. In this context, this review paper summarizes the last 15 years of research on canola and rapeseed proteins as food emulsifiers. It discusses the protein extraction methods, modifications made to improve emulsification, emulsion composition, preparation protocols, and emulsion stability results. The need for further improvement in the scope of the research and reducing the knowledge gap is also highlighted, which could be useful for the food industry to rationally select canola proteins and optimize the processing parameters to obtain products with desirable attributes.

In this experiment, a multi-enzyme method was used to prepare rapeseed peptides by stepwise hydrolysis of rapeseed proteins. Based on four single-factor experiments of hydrolysis temperature, hydrolysis time, pH value and enzyme addition, the response surface methodology was used to optimize the hydrolysis conditions of rapeseed proteins. The results showed that the optimal experimental conditions were 55.5 ℃ of temperature, 90 min of hydrolysis time, 10.5 of pH, and 10 400 U/g of enzyme addition. The hydrolysis degree was 31.64% under these conditions. The second hydrolysis was carried out by using compound flavor protease. The debittering effect of rapeseed peptide was remarkable, and the hydrolysis degree reached more than 38% after 120 min of hydrolysis time. This experiment improved the extraction rate of rapeseed peptides and obtained rapeseed peptides with good debittering effect.

This study aims to investigate the influence of alkaline treatment duration (0–5 h) on the physicochemical properties and emulsifying performance of rapeseed protein during pH-shift process. Results showed that a 4-h alkaline treatment significantly reduced the particle size of rapeseed protein and led to a notable decrease in disulfide bond content, as well as alterations in subunit composition. Moreover, solubility of rapeseed protein increased from 18.10 ± 0.13% to 40.44 ± 1.74% post-treatment, accompanied by a ∼ 40% enhancement in emulsifying properties. Morphological analysis revealed superior plasticity and sharper contours in 4-h alkali-treated rapeseed protein emulsions compared to untreated counterparts. Rheological analysis indicated higher viscosity and elasticity in the alkali-treated group. Overall, 4-h alkaline treatment markedly enhanced the multifaceted functional attributes of rapeseed protein during pH-shift process, rendering it a promising emulsifier in the food industry. [Display omitted] • Solubility and emulsifying properties of rapeseed protein significantly increased after pH-shift treatment. • Decreased particle size, altered disulfide bonds, and subunit changes of rapeseed protein were observed. • A 70% oil phase with 4% or 6% rapeseed protein content yielded favorable emulsion systems. • pH-Shift treatment increased viscosity and elasticity of rapeseed protein emulsion. [ABSTRACT FROM AUTHOR]

The objective of this study was to extract the rapeseed protein from by-products and further examine the effect of lab-made rapeseed protein on the droplet size, microstructure, colour, encapsulation and apparent viscosity of emulsions. Rapeseed protein-stabilised emulsions with an increasing gradient of milk fat or rapeseed oil (10, 20, 30, 40 and 50%, v/v) were fabricated using a high shear rate homogenisation. All emulsions showed 100% oil encapsulation for 30 days of storage, irrespective of lipid type and the concentration used. Rapeseed oil emulsions were stable against coalescence, whereas the milk fat emulsion showed a partial micro-coalescence. The apparent viscosity of emulsions raised with increased lipid concentrations. Each of the emulsions showed a shear thinning behaviour, a typical behaviour of non-Newtonian fluids. The average droplet size was raised in milk fat and rapeseed oil emulsions when the concentration of lipids increased. A simple approach to manufacturing stable emulsions offers a feasible hint to convert protein-rich by-products into a valuable carrier of saturated or unsaturated lipids for the design of foods with a targeted lipid profile.

Copyright of Journal of Food Safety & Quality is the property of Journal of Food Safety & Quality Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

This study aimed to investigate the physical stability, oxidation, digestibility and β-carotene sustained-release properties of Pickering emulsions stabilized by rapeseed protein (RP) complexed with chitosan (CS). The results showed that adding CS to RP decreased the RP mean particle size from 3575.0 to 130.9 nm, increased its zeta-potential from 29.6 to 41.4 mV, changed its tertiary structure, and enabled its uniform dispersion. Additionally, CS addition improved RP interfacial properties at air/water and oil/water interfaces, thereby enhancing its emulsification activity and stability. Rheological property analysis exhibited that RP/CS complex had a smaller storage modulus (G′) and loss modulus (G") as well as a higher apparent viscosity. Moreover, the RP/CS complex stabilized emulsions showed a smaller average particle size of 100–1500 nm, a higher zeta-potential of 58–66 mV and better physical stability, thus better tolerating environmental factors such as time, temperature and salt ions. Furthermore, the RP/CS complex stabilized emulsions showed better antioxidant properties with a lower peroxide value (POV) and thiobarbituric acid reactant value (TBARS). Finally, the RP/CS complex emulsions exhibited better antidigestive stability and could slow down the β-carotene release rate. These results provide a theoretical basis for the application of RP/CS complex as a new food emulsifier in the nanocolloid transport system. [Display omitted] • Adding chitosan (CS) made rapeseed protein (RP) more uniform and stable in water. • CS addition improved RP interfacial tension and increased its emulsifying property. • RP/CS complex prevented emulsion stratification and improved its physical stability. • RP/CS complex reduced oil droplets oxidation rate during accelerated oxidation. • RP/CS complex could slow down β-carotene release rate as a stabilizer. [ABSTRACT FROM AUTHOR]

To improve the techno-functional properties of rapeseed protein (RP), this work tried to regulate the molecular structure of RP via inducing the co-assembly of RP with zein and whey protein (WP). The results showed that WP and zein mainly regulate the folding process of RP through hydrophobic and disulfide bonds, thereby altering the structural conformation and forming stable complex RP (CRP). WP addition not only increased the number of surface charges and hydrophilicity of proteins, but also decreased their sizes, improved the water solubility, as well as the availability of active groups. These changes significantly increased the foaming capacity (from 60 % to 147 %) and in vitro gastric digestion rate (from 10 % to 60 %) of CRP. Besides, WP also contributed to the formation of gels and the regulation of their textural profiles. Comparatively, zein improved the hydrophobicity of CRP and balanced degree of intermolecular forces, which effectively increased the emulsifying activity index of CRP from 22 m2/g to 90 m2/g. Zein decreased the hardness, springiness and water-holding capacity of gel, but increased its gumminess and chewiness. Overall, both WP and zein effectively changed the structural conformation of RP, and improved its techno-functional properties, which provides an effective strategy to modify protein. [Display omitted] [ABSTRACT FROM AUTHOR]

Rapeseed is a promising plant protein source yet to be fully explored. Traditionally, rapeseed proteins are extracted from hexane-defatted press cake at high alkaline conditions to maximise protein recovery. Instead of the traditional approach, this study explored the effects of extracting proteins from the whole-kernel seed, focusing on assessing the hexane defatting process followed by gentle protein extraction at neutral pH compared with pH 8.5. Extraction at neutral pH resulted in a napin-rich protein extract, while alkaline conditions favoured cruciferin extraction as expected. Hexane defatting destroyed the oil bodies's structure while detaching the cell membrane from the cell wall, causing dehydration, and enabling interactions between the seed constituents. Increasing cycles of hexane treatment greatly reduced the total protein recovery by 9 g/100 g under neutral pH and >60 g/100 g under mild alkaline conditions which affected the protein structure, leading to a more rigid structure with a slightly higher melting temperature. [Display omitted] • Hexane defatting caused cell membrane, oil, and protein bodies modifications. • Hexane defatting reduced protein yield up to relatively 60 g/100 g after mild alkaline extraction. • Hexane-defatted protein was more rigid and needed higher energy for denaturation. [ABSTRACT FROM AUTHOR]

Our previous experiments found that rapeseed protein (RP) has applicability in low-moisture textured proteins. The amount of RP added is limited to <20 %, but the addition of 20 % RP still brings some negative effects. Therefore, in order to improve the quality of 20%RP textured protein, this experiment added different proportions of sodium tripolyphosphate (STPP) to improve the quality of the product, and studied the physical-chemical properties and molecular structure changes of the product to explore the possible modification mechanism. The STPP not only improved the expansion characteristics of extrudates, but also increased the brightness of the extrudates, the rehydration rate. In addition, STPP increased the specific mechanical energy during extrusion, decreased the material mass flow rate. Furthermore, STPP decreased the starch digestibility, increased the content of slow-digesting starch and resistant starch. STPP increased the degree of denaturation of extrudate proteins, the proportion of β-sheets in the secondary structure of proteins, as well as the intermolecular hydrogen bonding interactions. The gelatinization degradation degree of starch molecules also decreased with the addition of STPP. STPP also increased the protein-starch interactions and enhanced the thermal stability of the extrudate. All these indicate that STPP can improve the physical-chemical properties of extrudate. • The addition of STPP improve the physical properties of the textured protein supplemented with 20 % rapeseed protein. • The addition of STPP increases the viscosity of the melt and increases the mechanical shear action. • STPP change the molecular properties of the protein and starch components of the extrusion process. • STPP decreased the hydrolysis rate of starch components and increased the proportion of resistant starch. [ABSTRACT FROM AUTHOR]

Providing sufficient food to a growing population while addressing the rise of food-related diseases requires innovative solutions. The use of plant proteins as structuring agents for oils has shown potential because of their healthier fatty acid profiles compared to solid fats. Thus, this study aims to investigate the potential correlations between the properties of proteins and their oil binding capacity (OBC) to provide insights into their applicability in structuring oil. Two samples each of sunflower, rapeseed, and soy protein products obtained from different manufacturers were denatured by heat and dispersed in oil after freeze-drying. Whey protein isolate (WPI) was used as a reference. The results indicate that, with some modifications, rapeseed and sunflower proteins can bind amounts of oil (3.7 oil [g]/protein [g]) comparable to that of WPI (4.04 oil [g]/protein [g]). However, the extraction process affects the final results and the texture of the protein-oil dispersion. Moreover, the protein solubility in NaCl, carbohydrate content, particle size, and the quantity of α-helical structures are positively correlated with the OBC, whereas an increase in the firmness of the dispersion is negatively associated with it. There was no correlation found between the changed β-sheet structure resulting from the heat treatment and the OBC. This study emphasizes the ability of plant proteins to structure oil and explains how to evaluate the physical and structural properties of plant proteins. Technical insights that may lead to the production of more sustainable and healthier food products are provided. [ABSTRACT FROM AUTHOR]

Copyright of Science & Technology of Cereals, Oils & Foods is the property of Science & Technology of Cereals, Oils & Foods Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

BACKGROUND The use of rapeseed protein for human nutrition is primarily limited by its strong bitterness, which is why the key bitter compound, kaempferol 3‐O‐(2‴‐O‐sinapoyl‐β‐sophoroside), is enzymatically degraded. RESULTS: Mass spectrometry analyses of an extract from an untreated rapeseed protein isolate gave three signals for m/z 815 [M‐H]. The predominant compound among the three compounds was confirmed as kaempferol‐3‐O‐(2‴‐O‐sinapoyl‐β‐sophoroside). Enzymatic hydrolysis of this key bitter compound was achieved using a sinapyl ester cleaving side activity of a ferulic acid esterase (FAE) from the basidiomycete Schizophyllum commune (ScoFAE). Recombinant ferulic acid esterases from Streptomyces werraensis (SwFAE) and from Pleurotus eryngii (PeFAE) possessed better cleavage activity towards methyl sinapate but did not hydrolyze the sinapyl ester linkage of the bitter kaempferol sophoroside. CONCLUSION: Kaempferol‐3‐O‐(2‴‐O‐sinapoyl‐β‐sophoroside) was successfully degraded by enzymatic treatment with ScoFAE, which may provide a means to move the status of rapeseed protein from feed additive to food ingredient. © 2021 The Authors. Journal of The Science of Food and Agriculture published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

The aim of the study was to analyze the influence of rapeseed protein isolate on physico-chemical properties, sensory attributes and storage of gluten-free bread prepared on the basis of corn and potato starch mixture with the addition of pectin and guar gum. Starches used in bread formulation were replaced with rapeseed protein isolate in the amounts 6–15%. The bread was characterized in terms of physical properties, including volume, crumb structure and color, which was accompanied with sensory assessment. Texture and thermal properties were determined during 3 days of storage. It was observed that the presence of rapeseed protein, especially at higher levels, caused an increase in bread volume and density of pores and a decrease in crumb porosity, as compared to the control. Partial replacement of starch with rapeseed protein caused a significant increase of b* parameter, reflecting rising yellowness, which positively influenced bread acceptance. Rapeseed protein limited bread staling during storage in comparison to control sample. The results demonstrate that rapeseed protein could become a valuable component of gluten-free bread, as it provides valuable amino acids, but also beneficially influences quality characteristics. [ABSTRACT FROM AUTHOR]

This study investigated the potential of rapeseed protein as a novel alternative protein source in meat analogs produced by extrusion cooking technology. To study the substitutability of rapeseed protein to soybean protein, the addition ratios of rapeseed protein to soybean protein in the extrusion experiment were 0:50, 10:40, 20:30, 30:20, 40:10 and 50:0 (w/w), respectively. The results showed that adding 0–20% rapeseed protein not only decreased the specific mechanical energy and mass flow rate of the mixture during extrusion, but also enhanced the hardness and chewiness of the extrudates while reducing their elasticity and resilience. In addition, increasing the amount of rapeseed protein may lead to decreased expansion characteristics, internal pore structure, and water absorption rate of the extrudates, as well as a decrease in brightness and an increase in redness on the surface. Weibull model could well describe the rehydration behavior for dynamic fitting of the extrusion rehydration process. Moreover, with the increase of rapeseed protein substitution, the content of disulfide bonds, and the proportion of relatively ordered protein secondary structures with high stability increased, and the degree of protein denaturation decreased. Besides, the degree of starch gelatinization reduced and the thermal stability of extrudates improved. Interaction analysis indicated that disulfide bonds are the primary force maintaining protein-mediated interactions in the extrudates. The incorporation of rapeseed protein shortened the mean residence time of molten feedstock and shifted the flow state to plug flow. Overall, our investigation suggests that within low levels of addition (≤20%, w/w), rapeseed protein has the potential to partially substitute for the soybean protein-based textured proteins. High substitution levels or complete substitution are not feasible due to the relatively low expansion and rehydration rates. [Display omitted] • The properties of the extrudates with 20% rapeseed protein are acceptable. • Low hydration and gelation of rapeseed protein decrease extrudate expansion rate. • Weibull model can fit the rehydration process of extrudates well. • Rapeseed protein shortens the residence time and mixing degree during extrusion. [ABSTRACT FROM AUTHOR]

[Display omitted] • Unmodified rapeseed protein concentrate showed good fibrous structure at pH 6. • Fermentation and incubation at acidic pH hindered fibrous structure formation. • Regular pH shift to 4 and back to 6 showed excellent fibrous structure formation. • Peptide formation and bitterness was detected in fermented and incubated samples. • Fermentation decreased chemical off-notes present in rapeseed protein concentrate. This study aimed to modify the sensory properties of rapeseed protein concentrate using a combination of fermentation and high-moisture extrusion processing for producing meat analogues. The fermentation was carried out with Lactiplantibacillus plantarum and Weissella confusa strains, known for their flavour and structure-enhancing properties. Contrary to expectations, the sensory evaluation revealed that the fermentation induced bitterness and disrupted the fibrous structure formation ability due to the generation of short peptides. On the other hand, fermentation removed the intensive off-odour and flavour notes present in the native raw material. Several control treatments were produced to understand the reasons behind the hindered fibrous structure formation and induced bitterness. The results obtained from peptidomics, free amino ends, and solubility analyses strongly indicated that the proteins were hydrolysed by endoproteases activated during the fermentation process. Furthermore, it was suspected that the proteins and/or peptides formed complexes with other components, such as hydrolysis products of glucosinolates and polysaccharides. [ABSTRACT FROM AUTHOR]

The purpose of this study was to evaluate the potential of rapeseed proteins including Napin, Cruciferin, and Oleosin as precursors of antimicrobial peptides (AMPs), and to investigate physicochemical properties, secondary structures, toxicity, and allergenicity of AMPs using several bioinformatics tools such as BIOPEP, CAMP, APD, SOPMA, ToxinPred, and AllergenFP. A total of 26 novel AMPs were obtained by in silico hydrolysis using nine proteases, and six peptides were tested positive by all the four algorithms including Random Forest (RF), Support Vector Machines (SVM), Artificial Neural Network (ANN), and Discriminant Analysis (DA). More AMPs were generated from Cruciferin than from Napin and Oleosin. Trypsin was the most effective enzyme for AMPs production compared with other used proteases. About two-third of peptides were cationic. Interestingly, most peptides were extended AMPs. All AMPs were predicted to be non-toxic, and 14 peptides were non-allergenic. These results indicate that rapeseed protein is a good potential source of AMPs as demonstrated by in silico analyses and the theoretical knowledge obtained provides a basis for further development and production of rapeseed AMPs. Practical applications: Rapeseed protein is a high-quality plant protein resource. However, it is usually used as animal feed or fertilizer. Effective enzymatic hydrolysis of rapeseed protein can release bioactive peptides and improve the utilization value. This study indicates that rapeseed protein is a good potential source of AMPs as demonstrated by in silico analyses. The theoretical knowledge obtained provides a basis for further development and production of rapeseed AMPs. [ABSTRACT FROM AUTHOR]

Rapeseed cake serves as a by-product in the oil extraction industry, characterized by its elevated protein content. However, the presence of antinutritional factors limits the utilization of rapeseed cake as a viable protein source. In this study, different doses of γ-irradiation were used to irradiate rapeseed cake and rapeseed protein isolate was extracted through a modified alkaline solution and acid precipitation method from rapeseed cake. The chemical composition and in vivo acute toxicity of rapeseed protein isolate were determined. The protein recovery rate of rapeseed protein isolate was 39.08 ± 3.01% after irradiation, while the content of antinutritional factors was significantly reduced. Moreover, γ-irradiation did not have any experimentally related effects on clinical observations or clinicopathology in mice. Overall, the reduced antinutrients and increased functional properties suggest that the irradiation of rapeseed cake (<9 kGy) could be utilized as a pre-treatment in the development of rapeseed cake-based value-added protein products., (© 2024 The Author(s).)

Brassica napus L. is a vegetable oil crop, commonly known as rapeseed (or canola). It is widely used as a source of oil and protein for food and industrial applications, but also as a remedy, and in a field of attraction or as an ornament due to its diverse flower colors. Every part of rapeseed is useful, even the waste, which could be used to feed animals, or recycled. In this review, the use of rapeseed in these applications is presented, starting with the preparation of oil and protein from the seeds, before their release in the market, to the utilization of natural unprocessed rapeseed. Progress in rapeseed exploitation for food, remedy, energy source, and industrial applications are analyzed to show variability in diverse findings, to provide insights and progressive descriptions of rapeseed usage to other scholars. Moreover, advancements in breeding for rapeseed improvement were described. In the future, strategies could be developed or improved to avoid or decrease crop losses, but also to increase interest in propagating the valuable traits of rapeseed.

Highlights • The composite film was prepared by rapeseed protein hydrolysate and chitosan. • The hydrolysate could be better blended with chitosan under acidic conditions. • The composite films present dense, homogenous, and smooth structure. • The α-helix content in films is positive correlation with mechanical properties. • The antimicrobial activities of the composite films were better than chitosan film. Abstract The composite films were prepared by mixing rapeseed protein hydrolysate with chitosan. Upon increasing the degree of hydrolysis, rapeseed protein enhanced its compatibility with chitosan, thus making composite films denser. The tensile strength of films was increased from 16.04 to 23.46 MPa with increasing the degree of hydrolysis from 0% to 12%. Moreover, addition of chitosan enhances the mechanical properties of the rapeseed protein films, the α-helix content in the secondary structure of the rapeseed protein from 15.4% to 25.0%. And it is hydrogen bonding, the main force between two components that contributed to good compatibility, which supported by analyses of Fourier transform infrared spectroscopy and scanning electron microscopy. The results of the antibacterial properties of the composite film with 12% degree of hydrolysis were better compared with the chitosan film. Taken together, our results provide insights for the further application of rapeseed protein in making edible films. [ABSTRACT FROM AUTHOR]

[Display omitted] • Assigning different weights to the wavelengths realizes feature selection. • Bounding band weights between 0 and 1 demonstrates the interpretability of the model. • Retaining the original information of all spectral bands. • Model has more general, more accurate, and more robust performance than traditional methods. Compared with the complexity of chemical methods, near-infrared spectroscopy (NIRS) is widely used in the detection of protein content because of its advantages of being fast and non-destructive. Aiming to tackle the problem that the raw near-infrared spectroscopy contains many redundant wavelengths, which affects the accuracy of quantitative prediction and requires expertise to process, we propose an end-to-end network: Band Reweighted Network (BR-Net) that automates wavelength reweighted and quantitative prediction of protein content in rapeseed. Unlike extracting part of wavelengths by the traditional wavelength selection methods, BR-Net retains all spectral wavelengths and assigns different weights to the wavelengths to express the correlation with the corresponding concentration, which enables wavelength selection without ignoring the information contained in the less relevant wavelengths. We compare BR-Net with traditional selection methods such as SPA, LARS, CARS, and UVE to verify its efficiency and robustness, finding that the R2 of the training set and test set are 0.9797 and 0.9215, the RMSEC and RMSEP are 0.4053 and 0.8501, respectively, and the RPD is 3.5686, which prove BR-Net outperforms all the traditional methods. The network described here is universally applicable to a variety of NIR quantitative analyses. [ABSTRACT FROM AUTHOR]

• Various bioactive peptides were encrypted in rapeseed protein by in silico analysis. • Novel ACE inhibitory peptides FQW, FRW, CPF were identified from rapeseed protein. • The peptides were predicted to be non-toxic and not allergens. • The three peptides could interact with ACE active site, and coordinate with Zn2+. • Rapeseed protein could be an excellent source of ACE inhibitory peptides. Plant-derived bioactive peptides have drawn much attention because of their physiological functions. This study aimed to evaluate bioactive peptides in rapeseed protein and identify novel angiotensin Ⅰ-converting enzyme (ACE) inhibitory peptides using bioinformatics methods. A total of 24 kinds of bioactive peptides were encrypted in the 12 selected rapeseed proteins by analysis in BIOPEP-UWM, with higher occurrence frequency of dipeptidyl peptidase Ⅳ (DPP-Ⅳ) inhibitory peptides (0.5727–0.7487) and ACE inhibitory peptides (0.3500–0.5364). Novel ACE inhibitory peptides FQW, FRW and CPF were identified by in silico proteolysis, and they had strong inhibitory effects on ACE in vitro , showing IC 50 values of 44.84 ± 1.48 μM, 46.30 ± 1.39 μM and 131.35 ± 3.87 μM, respectively. Molecular docking results displayed that these three peptides were able to interact with ACE active site via hydrogen bonds and hydrophobic interactions, and coordinate with Zn2+. It suggested that rapeseed protein could be a good source for the production of ACE inhibitory peptides. [ABSTRACT FROM AUTHOR]

Plant proteins have become increasingly important for ecological reasons. Rapeseed is a novel source of plant proteins with high biological value, but its metabolic impact in humans is largely unknown. A randomized, controlled intervention study including 20 healthy subjects was conducted in a crossover design. All participants received a test meal without additional protein or with 28 g of rapeseed protein isolate or soy protein isolate (control). Venous blood samples were collected over a 360-min period to analyze metabolites; satiety was assessed using a visual analog scale. Postprandial levels of lipids, urea, and amino acids increased following the intake of both protein isolates. The postprandial insulin response was lower after consumption of the rapeseed protein than after intake of the soy protein (p < 0.05), whereas the postmeal responses of glucose, lipids, interleukin-6, minerals, and urea were comparable between the two protein isolates. Interestingly, the rapeseed protein exerted stronger effects on postprandial satiety than the soy protein (p < 0.05). The postmeal metabolism following rapeseed protein intake is comparable with that of soy protein. The favorable effect of rapeseed protein on postprandial insulin and satiety makes it a valuable plant protein for human nutrition.

Rapeseed protein isolate (RPI) and dextran conjugates were prepared by traditional and ultrasonic assisted wet-heating. The effects on the grafting degree ( GD ), structure, functionality, and digestibility of conjugates were studied. Ultrasonic frequency, temperature, and time all significantly affected the GD . Under the optimum conditions (temperature of 90 °C and time of 60 min), compared to traditional wet-heating, ultrasonic treatment at 28 kHz significantly increased the GD by 2.12 times. Compared to RPI, surface hydrophobicities of conjugates were significantly decreased by graft and ultrasonic treatments. Sodium dodecyl sulfate–polyacrylamide gel electrophoresis (SDS-PAGE) and amino acid composition results confirmed that traditional graft reaction involved cysteine (Cys) and lysine (Lys) whereas the ultrasonic assisted one involved only Cys. Both were from the 12S globulin subunit and cruciferin. Fourier transform infrared spectrum (FT-IR) and circular dichroism (CD) results showed that graft treatment significantly changed secondary structure and ultrasonic treatment had the greatest impact on the decrease in the β-sheet (19.1%) and the increase in the random coil (49.6%). Graft and ultrasonic treatments both made surface structure looser and more porous. The two treatments also caused molecular weight to become bigger, and ultrasonic treatment had the greatest effect on the increase (68.2%) in 110–20.5 kDa. Structural modifications of RPI by grafting to dextran caused improvements of solubility (at pH 5–6), emulsifying activity (at pH 4–10), emulsion stability (at pH 4–5 and 9–10), and thermal stability (at temperature 90–100 °C). The digestibility of conjugates was decreased by graft and ultrasonic treatments and the conjugates were mainly digested in the intestinal phase. The ultrasonic assisted wet-heating was an efficient and safe method for producing RPI-dextran conjugates and improving the utilization value of rapeseed meal. [ABSTRACT FROM AUTHOR]

We evaluated the effect of sequential dual-frequency ultrasound ( SDFU) pretreatments on rapeseed protein enzymolysis, using alcalase as a model enzyme. Hydrolysed protein concentrations, enzymolysis kinetics and thermodynamic parameters were investigated. The results showed that the hydrolysed rapeseed protein concentration following SDFU pretreatments was higher compared to that of the control for up to 75 min of enzymolysis at various substrate concentrations of 5-25 g L−1; both control and SDFU pretreatment groups showed first-order reaction kinetics. Compared to the control, the Michaelis-Menten constant ( KM) value decreased remarkably by 17.61%, while an increase in the binding frequency between enzyme and substrate ( KA) by 10.47% was observed. The thermodynamic parameters, enthalpy, entropy and activation energy were reduced in the SDFU pretreatment group compared to the control by 31.78%, 18.0% and 29.56%, respectively. SDFU pretreatment showed little effect on Gibbs free energy at the various temperatures studied. [ABSTRACT FROM AUTHOR]

Plant protein have long been opposed to animal protein because some plant protein present a relative mismatch between their amino acid pattern and human requirements for the renewal of body protein. Nevertheless, beyond its theoretical relevance to match the metabolic demand for protein metabolism, the amino acid pattern of dietary protein may also be of importance in the nutritional prevention of certain metabolic diseases. Of major public health concern is the metabolic syndrome, a cluster of risk factors associating obesity, insulin resistance, endothelial dysfunction, and low-grade inflammation. Two amino acids may be of importance in the pathophysiology of the metabolic syndrome: cysteine, the glutathione precursor, and arginine, the nitric oxide precursor. In this context, rapeseed protein, which is rich in cysteine and a good source of arginine, is an attractive candidate for studying the potential of dietary protein to prevent insulin resistance and related metabolic/ physiological abnormalities in the setting of the metabolic syndrome. After having presented a study demonstrating the high postprandial nitrogen utilization of rapeseed protein in humans, this review report two studies from our group showing that 1) rapeseed protein prevents the onset of insulin resistance induced by a diet rich in saturated fatty acids and sucrose in rats; 2) rapeseed protein alleviates the postprandial vascular endothelial dysfunction and oxidative stress coming after a meal rich in saturated fatty acids and sucrose. The beneficial preventive effects can be accounted for, at least to some extent, by the high cysteine and arginine content of the rapeseed protein. Studies are urgently needed to assess the beneficial effect of this emerging protein source in humans.

The aim of this study was to investigate the performance of rapeseed protein isolate (RPI) or concentrate (RPC) as such and after lactic acid bacteria fermentation as ingredients in composite wheat baking. Bread recipes were developed replacing wheat flour with RPI (10%) or RPC (20%) to obtain a high protein bread. Fermentation of the rapeseed protein ingredients with Weissella confusa A16 enabling synthesis in situ of dextran contributed to obtaining bread with improved textural properties. The in situ produced dextran in RPI (6.1% dry matter) and RPC (5.7% dm) increased the bread specific volume (10% and 14%, respectively) and decreased crumb hardness (35% and 25%, respectively) compared to the respective control breads. Furthermore, fermentation of RPC significantly improved the free amino acid profiles e.g., lysine, methionine, and isoleucine, which are deficient in wheat bread. Protein digestibility in vitro was significantly enhanced in the breads containing fermented RPI, but not in the one with fermented RPC, probably due to the higher level of condensed tannins in RPC after fermentation. [ABSTRACT FROM AUTHOR]

The mechanism of ultrasound field promoting enzymolysis efficiency is difficult to study, because the reaction system mixes with enzymes, proteins and hydrolysates. Immobilized enzyme is a good option that can be used to investigate the mechanism by separating enzymes out from the system after enzymolysis. The objective of this study was by using immobilized Alcalase to investigate the effects and mechanisms of the promotion of dual-frequency ultrasound (DFU) assisted-enzymolysis on rapeseed protein. Based on single factor experiments, response surface methodology model with three factors – hydrolysis time, power density and solid–liquid ratio at three levels was utilized to optimize the degree of hydrolysis (DH). Circular dichroism (CD) was used to analyze the secondary structure change of the protein, scanning electron microscopy (SEM) was used to analyze the surface microstructure change of the enzyme. The results showed that with DFU assisted-enzymolysis, the DH increased by 74.38% at the optimal levels for power density 57 W/L, solid–liquid ratio 5.3 g/L and enzymolysis time 76 min. After DFU assisted-enzymolysis, the yield of soluble solids content, including protein, peptides and total sugar in hydrolysate increased by 64.61%, 40.88% and 23.60%, respectively. CD analysis showed that after DFU assisted-enzymolysis, the number of α-helix and random coil decreased by 10.7% and 4.5%, β-chain increased by 2.4%. SEM showed that the degree of surface roughness of immobilized Alcalase increased. The above results indicated that the improvement of hydrolysis by DFU assisted-enzymolysis was achieved by enhancing the solid solubility, changing the molecular structure of protein and increased the surface area of immobilized enzyme. [ABSTRACT FROM AUTHOR]

Influence of maleylation on the physicochemical and functional properties of rapeseed protein isolate was studied. Acylation increased whiteness value and dissociation of proteins, but reduced free sulfhydryl and disulfide content ( p < 0.05). Intrinsic fluorescence emission and FTIR spectra revealed distinct perturbations in maleylated proteins' tertiary and secondary conformations. Increase in surface hydrophobicity, foaming capacity, emulsion stability, protein surface load at oil-water interface and decrease in surface tension at air-water interface, occurred till moderate level of modification. While maleylation impaired foam stability, protein solubility and emulsion capacity were markedly ameliorated ( p < 0.05), which are concomitant with decreased droplet size distribution ( d ). In-vitro digestibility and cytotoxicity tests suggested no severe ill-effects of modified proteins, especially up to low degrees of maleylation. The study shows good potential for maleylated rapeseed proteins as functional food ingredient. [ABSTRACT FROM AUTHOR]

BACKGROUND The disadvantages which stem from the use of traditional enzymolysis of protein has necessitated the need to employ sweeping frequency and pulsed ultrasound (SFPU) in the pretreatment of rapeseed protein prior to proteolysis in order to bring about improvement in enzymolysis efficiency. Further, in order to determine the mechanism of ultrasound-accelerated enzymolysis of RP, the effects of SFPU on the kinetics, thermodynamics, molecular conformation and microstructure of RP were investigated. RESULTS Kinetic studies showed that SFPU pretreatment on RP improved enzymolysis by decreasing the apparent constant KM significantly ( P < 0.05) by 32.8% and reducing the thermodynamic parameters Ea, Δ H and Δ S by 16.6%, 17.7% and 9.2% respectively. Fluorescence spectra revealed that SFPU pretreatment induced molecular unfolding, causing more hydrophobic groups and regions inside the molecules to be exposed to the outside. Circular dichroism analysis indicated that SFPU pretreatment decreased the α-helix content by 16.1% and increased the random coil content by 3.6%. In addition, scanning electron microscopy showed that SFPU pretreatment increased the specific surface area of RP. CONCLUSION Ultrasound pretreatment is an efficient method in RP proteolysis to produce peptides through its impact on the molecular conformation and microstructure of proteins. © 2015 Society of Chemical Industry [ABSTRACT FROM AUTHOR]