Food Biopolymers Research Articles

Multitechnique approaches for characterising phase behaviour in food biopolymer systems

SummaryUnderstanding the phase behaviour of biopolymer composites is vital for various technological applications, such as developing functional foods, nutraceuticals, encapsulation, isolation and fractionation of enzymes and proteins. The growing consumer demand for healthier food products pressures the food and nutraceutical industries to innovate while maintaining traditional texture and nutritional quality. This review critically examines various analytical techniques, including spectroscopic, microscopic, calorimetric, rheological, viscometry, and diffraction methods, used to study phase behaviour. Each technique provides unique insights into phase behaviour mechanisms at micro and macroscopic levels, with respective advantages and limitations discussed. The review advocates for a multi‐technique approach for a comprehensive understanding of phase behaviour and highlights the development of in situ probing techniques with minimal sample pre‐processing as a promising advancement. These innovations are expected to significantly enhance the practical applications of these techniques in the food industry, meeting current consumer demands without compromising traditional qualities.

Development of novel protein-rich foods: Studies of composite hydrogels formed from potato proteins and gellan gums with different degrees of acylation

The textural attributes of mixed hydrogels formed from potato protein (PP) and gellan gum (GG) were examined for their potential application as novel protein-rich foods (NPFs). Initially, the properties of gels formed by the individual biopolymers were characterized using dynamic shear rheology, compression testing, and confocal fluorescence microscopy. Rheological analysis revealed that PP dispersions formed irreversible heat-set gels, whereas GG formed reversible cold-set gels at lower temperatures. The effects of adding PP to high acyl gellan gum (HA-GG) or low acyl gellan gum (LA-GG) solutions on the microstructure and rheology of the mixed gels formed were then examined. The PP/LA-GG composite gels had a highly heterogeneous microstructure consisting of protein-rich and polysaccharide-rich regions. In contrast, the PP/HA-GG composite gels had a more uniform microstructure. Interestingly, the incorporation of the PP weakened the PP/LA-GG composite gels (antagonism) but strengthened the PP/HA-GG composite gels (synergism), which was mainly attributed to their different impacts on gel microstructure. This study shows that semi-solid plant protein-dietary fiber composites can be formed with a variety of textural attributes by altering the nature and concentration of biopolymers used to formulate them. These mixed gels may be useful for the creation of NPFs. This study also highlights the complexity of the interactions between different food biopolymers and their impacts on food properties, highlighting the need for further research on understanding structure-function relationships in multicomponent biopolymer materials.

Impact of heat-set and cold-set gelling polysaccharides on potato protein gelation: Gellan gum, agar, and methylcellulose

The plant-based meat market is growing due to concerns about the sustainability of the modern food system. Plant-based meats are often constructed from blends of food biopolymers, such as plant proteins and polysaccharides. This study characterizes the thermal setting properties of potato protein (10%) and polysaccharide (2 wt%) mixtures containing polysaccharides with different reversible gelling behaviors: agar (cold set); gellan gum (cold set); or methyl cellulose (heat set). Each sample was heated above the thermal denaturation temperature of the potato proteins to promote protein unfolding, aggregation, and network formation. The addition of the polysaccharides tended to increase the complex shear modulus of the biopolymer blends before heating but increase or decrease it after heating depending on polysaccharide type. The shear modulus and hardness of the gels formed after heating tended to increase after addition of the cold-set polysaccharides but decrease after the addition of the heat-set polysaccharides, especially at refrigerator temperatures. Differential scanning calorimetry data showed that the potato proteins underwent irreversible denaturation after heating for all samples. Zeta-potential analysis showed that the potato proteins and all polysaccharides were negatively charged under the pH conditions used. There was greater water loss during heating for the composite gels containing methyl cellulose, which may have been due to its increase hydrophobicity at high temperatures. Appearance and microstructure analysis showed that phase-separation occurred after mixing the polysaccharides with the potato proteins, which was attributed to a segregation mechanism. The knowledge obtained from this study may help the food industry to optimize protein-polysaccharide blends to create gels with characteristics and structures that can mimic different plant-based meat products.

Tailoring Food Biopolymers into Biogels for Regenerative Wound Healing and Versatile Skin Bioelectronics

HighlightsThis food biopolymer-based biogel unites the challenging needs of elastic yet injectable wound dressing and skin bioelectronics in a single platform.This is the first demonstration of a hydrogel dressing that satisfies both deep and superficial wounds, and for the accelerated healing of diabetic wounds.Biogel-based flexible skin bioelectronic can serve as a “fever indicator” and monitoring human activities and tiny electrophysiological signals, providing important clinical information for the rehabilitation training of the wounded.

Extrusion-based 3D printing of food biopolymers: A highlight on the important rheological parameters to reach printability

Extrusion-based 3D printing of food biopolymers: A highlight on the important rheological parameters to reach printability

Impact of Flaxseed Gums on the Colloidal Changes and In Vitro Digestibility of Milk Proteins.

Flaxseed (Linum usitatissimum L.) mucilage is one of the most studied plant seed gums in terms of its techno-functional and health-promoting properties. Nonetheless, the interplay of flaxseed gum (FG) with other food biopolymers, such as milk proteins, under in vitro digestion conditions remains underexplored. The aim of the present work was to investigate the colloidal interplay between flaxseed gum (golden or brown) and milk proteins (sodium caseinate or whey protein isolate) under simulated in vitro digestion conditions and its relationship with the attained in vitro protein digestibility. The presence of flaxseed gum in the milk protein food models and in the oral food boluses obtained was associated with the occurrence of segregative microphase separation. Flaxseed gum exhibited a prominent role in controlling the acid-mediated protein aggregation phenomena, particularly in the sodium caseinate gastric chymes. The addition of FG in the food models was associated with a higher amount of intact total caseins and β-lactoglobulin at the end of the gastric processing step. Monitoring of the intestinal processing step revealed a very advanced cleavage of the whey proteins (>98%) and caseins (>90%). The degree of the milk protein hydrolysis achieved at the end of the intestinal processing was significantly higher in the systems containing flaxseed gum (i.e., 59-62%) than their gum-free protein counterparts (i.e., 46-47%). It was postulated that the electrostatic milk protein complexation capacity and, to a lesser extent, the thickening effect of flaxseed gum influenced the in vitro digestibility of the milk proteins.

Hybrid mixture theory-based modeling of transport of fluids, species, and heat in food biopolymers subjected to freeze-thaw cycles.

A hybrid mixture theory (HMT)-based unsaturated transport (pores not saturated with liquid) model was applied to a food matrix subjected to freezing and freeze-thaw cycles. The model can explain the fluid, species, and heat transport, ice formation, thermomechanical changes, and the freezing point depression occurring inside food biopolymers during freezing. Volume changes during freezing were calculated using the stresses due to pore pressure and the phase-change based mechanical strain. The Eulerian-Lagrangian transformation was performed for solving the equations using a finite element mesh in Lagrangian coordinates. The predicted temperature profiles for constant and fluctuating freezing temperature conditions showed agreement with experimental data with reasonable accuracy (RMSE = 2.86°C and 2.23°C, respectively). The multiscale transport model coupled with a physical chemistry-based relation was able to predict solute concentration and the freezing point depression in potatoes with greater accuracy than an empirical equation published in the literature. Sudden temperature fluctuations representing the opening and closing of a freezer door were investigated using this solution scheme, and conditions causing less damage to the food were identified. PRACTICAL APPLICATION: Food materials are subjected to freeze-thaw cycles during storage, shipping, and distribution to the consumers. The study uses numerical modeling and experimental validation to elucidate the principles affecting ice formation, solute migration, and temperature changes. Outcomes will allow processors to improve the quality of frozen foods with improved design of freezing operation, and storage and distribution strategies.

Influence of Hofmeister anions on structural and thermal properties of a starch-protein-lipid nanoparticle

A self-assembled soluble nanoparticle, composed of common food biopolymers (carbohydrate, protein) and lipid, was previously reported by our laboratory. Although carrying capacity of valuable small molecules was demonstrated, physical functional properties are also important. Given the stabilization or destabilization characteristics of Hofmeister anion on macromolecular structures, mainly on proteins, here, we investigated the effects of different sodium salts composed of different Hofmeister anions on the structural and thermal properties of these self-assembled nanoparticles for improved functionalities. The salts were added into the mixture that was prepared in a diluted system during nanoparticle formation. Increased concentration of kosmotropic anions, in contrast to the chaotropic anion tested, resulted in nanoparticles with higher molar mass, hydrodynamic radius, and molecular density with more compact arrangement. The nanoparticles produced in presence of kosmotropic anions dissociated at higher temperatures and required higher enthalpies compared to the control sample. Spherical nanoparticles were formed for the kosmotropes with shear thinning behavior, contrary to rod-like nanoparticles for the chaotrope with near-Newtonian behavior. These findings help to gain an understanding of the effect of altering environmental conditions on the nanoparticles with an aim of producing desired structures for applications.

Modification of β-lactoglobulin by phenolic conjugations: Protein structural changes and physicochemical stabilities of stripped hemp oil-in-water emulsions stabilized by the conjugates

Preventing lipid oxidation at the oil-water interface is critical for suppressing food emulsion deterioration and thus minimizing the economy loss. However, it is challenging to specifically localize the needed antioxidant species at the interface, failing in which often results in poor oxidative stability of emulsions. Here, we show that by grafting gentisic acid (GA) on β-lactoglobulin (βLG) at an optimal ratio, the βLG-GA conjugate can retain the emulsification property while improving the oxidative stability of the stripped hemp oil-in-water emulsion. Upon optimizing the conjugate production at a larger scale and a thorough characterization of the surface charge, surface hydrophobicity, and surface tension of the resultant conjugates bearing different GA grafting number (to the host βLG), a series of stripped hemp oil-in-water emulsions differing in GA abundance were prepared. The physical stability of emulsions was dependent on the structure, solubility, hydrophobicity, and GA grafting number of these conjugates. The existence of precipitants was noticed in the conjugates solutions, which impacted the size, physical and oxidative stability of the emulsions they stabilized when compared to the ones emulsified by the soluble conjugates. Remarkably, we discovered that under high GA grafting number, the antioxidant capacity of the conjugate is higher than that of the raw βLG, which suggested the potential use of the soluble conjugates with high GA grafting number as advanced emulsifier bearing good antioxidant activity. This work represents the structural basis of the functional improvement of the emulsions using protein-phenolic conjugates, which provides unique insights into the future design of multifunctional food biopolymers.

INNOVATIVE FOOD INGREDIENTS BASED ON THE COMPLEXES OF FOOD BIOPOLYMERS WITH PHOSPHATIDYLCHOLINE LIPOSOMES LOADED WITH FISH OIL AND CIRCUMIN: DEVELOPMENT AND IN VITRO STUDY

Water-soluble innovative food ingredients have been developed based on the complexes of food biopolymers (chitosan and milk proteins) with phosphatidylcholine liposomes (PC) loaded with curcumin and fish oil (FO). The developed ingredients could be used to fortify food products with adequate amounts of essential PUFAs and curcumin.

Freeze − thaw induced structuration of whey protein − alfalfa (Medicago sativa L.) galactomannan binary systems

The cryotropic gelation of food biopolymers is an alternative method to impart bespoke structural, textural, and functional characteristics to food colloids. The present work aims to explore the structuring performance of whey protein isolate (WPI) in the presence of alfalfa (Medicago sativa L.) galactomannan (AAG) under cryogenic processing. Aqueous WPI solutions (10% wt.) fortified with AAG (0–1% wt.) were subjected to five consecutive freeze – thaw cycles from 25 to −28 °C with an isothermal hold at −28 °C for 20 h. The development of the elastic modulus G′ in the WPI – AAG solutions was monitored throughout the cryogenic processing, and the cryogels obtained were characterised rheologically, structurally and physically. The addition of AAG in heat-treated WPI solutions induced an extensive microscopic phase separation, which was driven via a depletion – flocculation mechanism. Cryostructuration was governed by WPI, whilst AAG modulated the development of the microstructural features, the rheological behaviour and the stability of the cryogels when confronted with spontaneous and forced syneresis phenomena. It was postulated that the mechanisms of action of AAG were associated primarily with its ability to enhance the macroviscosity of the unfrozen water phase controlling the ripening of ice crystals (porogens) during the freezing step, and secondarily to its direct contribution via the partially structured hydrogel segments interpenetrating the formed protein network. Since the extent of phase separation eminently affected the cryogelation process, it was suggested that the use of at least 0.75% wt. of AAG was required in order to enhance the structural, rheological and physical stability of the WPI cryogels.

Development of novel biopolymer-based dendritic nanocomplexes for encapsulation of phenolic bioactive compounds: A proof-of-concept study

Phytoglycogen (PG) is a food-derived and glycogen-like nanoscale dendrimer. While its unique dendritic nanostructures offer promising structural features to harbor bioactive compounds, the strong hydrophilicity limits its applications for encapsulating lipophilic molecules. Here, we report a proof-of-concept study to modify PG with valeric acid (VAPG) and further interact with zein to form novel nanocomplexes for encapsulating hydrophobic antibacterial compounds. To avoid the use of toxic organic solvent, zein was solubilized and partially hydrolyzed by heating in 1 M NaOH at 90 °C or above for at least 4 min. Bioactive compound, thymol and eugenol was each co-solubilized with zein under above alkaline condition, followed by addition of PG and then neutralization by citric acid to induce the pH-driven self-assembly of nanocomplexes for encapsulation. Dynamic light scattering measurements indicated that the as prepared nanocomplexes had small particle size (66 nm) with narrow polydispersity and high zeta potential (−44 mV). Morphological observation revealed that these nanocomplexes had spherical shape and uniform size distribution. Both eugenol- and thymol-loaded VAPG nanocomplexes exhibited significantly improved bioactivity, including higher antioxidant activity and stronger antibacterial efficacy against foodborne human pathogens (Listeria monocytogenes and Salmonella Enteritidis), compared with un-encapsulated compounds and PG nanocomplexes. Our findings demonstrated an innovative strategy to develop dendritic nanoparticles from food biopolymers without using organic solvents or synthetic chemicals. The potential of these nanocomplexes as carriers for lipophilic and phenolic antimicrobial compounds opens up new avenues for nanotechnology-enabled approaches to ensure food safety and quality.

Construction of carboxymethyl konjac glucomannan/chitosan complex nanogels as potential delivery vehicles for curcumin

Construction of nanoscale delivery systems from natural food biopolymer complexes have attracted increasing interests in the fields of food industries. In this study, novel carboxymethyl konjac glucomannan/ chitosan (CMKGM/CS) nanogels with and without 1-ethyl-3-(3-dimethylaminopropyl) /N-hydroxysuccinimide) (EDC/NHS)-initiated crosslinking were prepared. The physicochemical and structural properties of the CMKGM/CS nanogels and their potential to be a delivery vehicle for curcumin were investigated. Compared to original uncrosslinked nanogels, crosslinking did not alter particle size and morphology but decreased zeta potential of nanogels. Fourier transform infrared spectrum confirmed that the amide linkage was formed between CMKGM and CS, which obviously enhanced the stability of crosslinked nanogels under gastrointestinal conditions. Furthermore, the crosslinked nanogels not only had higher encapsulation efficiency of curcumin but also better sustained release behavior under simulated gastrointestinal conditions. These findings suggested that the crosslinked CMKGM/CS nanogels might be a promising delivery system for nutrients.

Development of value‐added functional food by fusion of colored potato and buckwheat flour through hot‐melt extrusion

Thermal sensitivity of anthocyanin and low-water solubility of rutin limit their stability in processed foods and biological activity, respectively. Therefore, we aimed to develop a value-added food composite (VAFC) by mixing of anthocyanin-enriched potato (P) and rutin-enriched buckwheat (B) flour using soy lecithin (LCT) and vitamin E (Vita E) by hot-melt extrusion (HME). The VAFC was formulated using P 50% + B 50% (F1), P 45%+B 45%+LCT 10% (F2), and P 45%+B 45%+LCT 8%+Vita E 2% (F3). Results revealed that the solubility of the VAFC was significantly increased in F3 formulation. Likewise, total phenolic content, including single phenolic acids, total flavonoid including rutin and quercetin, total anthocyanin including single anthocyanins, and antioxidant capacity of the VAFC were significantly increased in F3 formulation. This study successfully demonstrated the approach of developing biopolymer-mediated functional VAFC from potato and buckwheat by HME. Practical applications People are becoming more conscious about daily consumed foods and their nutritional facts. Human health requires a well-balanced nutritional composition to keep well-functioning of the body. In this study, an approach was taken to develop anthocyanins, and rutin-enriched functional food by the mixes of potato and buckwheat by hot-melt extrusion. Food biopolymers and plasticizer were added to the food formulation to enhance the activity of the extrudate composites' functional attributes. Our developed formulation successfully improved the food composite's functional quality, which required industrialization for bulk production.

Study of the impact of the food biopolymer system on the clinical-biochemical status of white inbred mice in the invivo experiment

Studies have been conducted on the effect of the food biopolymer composition on the clinical-biochemical status of white inbred mice. The experiment showed that the development of laboratory animals was carried out without abnormalities with the complete safety of all individuals. Clinical-biochemical dynamics, glucose monitoring and the results of experiments in the exchange of macro and microelements of plasma of mouse blood indicated the normal flow of metabolic processes. In addition, the animals that consumed food additives had a higher rate of absorption of feed carbohydrates and a predominance of osteosynthesis processes in animal bone tissue. The studies conducted allow us to conclude that enrichment and trace elements increase the availability of trace elements, as well as activate the formation and strengthening of the bone tissue of the body.

Prediction of the properties of food biopolymer gels at the molecular-atomic level

The analysis of the main regularities, conditions and factors influencing the mechanism of structural changes in food biopolymer molecules during gelation using the laws of thermodynamics is carried out. A computational method for predicting the properties of gel-like food systems is considered. It makes it possible to establish the dependence of the characteristic viscosity of aqueous solutions of hydrocolloids and the hydrodynamic radius of biopolymer molecules on the charge of its molecular structures and the pH of the active acidity of the medium. On the example of gelatin, calculations are presented and it is shown that, in comparison with a neutral medium, the hydrodynamic radius of protein molecules increases approximately to (120–123) % both at high and low pH values, which makes it possible to predict the water-binding capacity of protein molecules and determine the optimal modes of technological processes.

Improving the functional properties of fish gelatin by conjugation with the water-soluble fraction of bitter almond gum.

Maillard-based conjugation may be a useful way of improving the functional properties of food biopolymers. In this study, covalent attachment of fish gelatin (FG) and the water-soluble fraction of bitter almond gum (SBAG) was performed through dry heating of FG-SBAG mixtures (1:1, 1:2, and 2:1) for 2days at 60°C and 80% relative humidity. The formation of the FG-SBAG conjugates was confirmed by FTIR spectroscopy and the degree of glycosylation (DG). The changing color observed in all FG-SBAG conjugates was indicative of Maillard reactions. Heat stability of conjugates increased with increasing SBAG ratio, and denaturation temperatures were consistent with DG. Conjugation improved radical scavenging activity, water holding capacity, emulsifying, and foaming properties of the FG (p < 0.05). Overall, the FG: SBAG (1:2) conjugate was the optimum combination for improving examined functional properties. The results suggest that this conjugate can potentially serve as a new ingredient in food formulations.

Rheological characterization of polysaccharide thickeners oriented for dysphagia management: Carboxymethylated curdlan, konjac glucomannan and their mixtures compared to xanthan gum

Novel naturally sourced thickeners from food biopolymers have always gained significantly increasing attention, particularly in food areas where the edible safety of thickeners is highly requested. Polysaccharides are commonly used in thickening fluids, enabling on-demand management of dysphagia where the fluidal food must be adequately thickened for patients. To customize and develop dysphagia diets, understanding and controlling the rheological properties of thickeners is of crucial importance. Herein, rheological behaviors of a novel thickener of carboxymethylated curdlan potential for dysphagia, a traditional food thickener of konjac glucomannan (KGM), and their mixtures were investigated in both water and model nutrition emulsions. The well-known dysphagia thickener of xanthan gum was taken as the reference, to allow a direct comparison of the efficacy and applicability among these thickened fluids. Comprehensively rheological characterizations such as shear-thinning, yielding, viscoelasticity, creep, and relaxation response behavior showed that the carboxymethylated curdlan, similar to xanthan, demonstrated unique viscosity-enhancing ability in both water and emulsions, presenting promising feasibility as a novel dysphagia-oriented thickener. However, although KGM showed excellent thickening capacity in water as expected, a prominent viscosity-lowering phenomenon was observed in the presence of maltodextrin. Considering the feature of KGM as salutary dietary fibers, the antagonistic effect of maltodextrin on the viscosity of KGM solutions provides an advantage to incorporate more dietary fibers in dysphagia diet formula.

High-Pressure Homogenization: Principles and Applications Beyond Microbial Inactivation

(Ultra) high-pressure homogenization ((U)HPH) is one of the emerging technologies being studied and developed for various applications in the food industry. (U)HPH was suggested as an effective tool for achieving microbial safety and extending the product shelf life of liquid foods in a continuous process while minimizing some negative attributes of thermal processing. The valve geometry, pressure level, inlet temperature, and the number of homogenization cycles are all factors affecting the level of microbial inactivation and the extent of the techno-functionalities of food biopolymers and matrices. Turbulence, high shear, cavitation, and temperature increase induced by (U)HPH treatments enhance emulsion stability, stabilize proteins in solutions, reduce particle size distributions, and increase the accessibility of health-promoting compounds. This review is a comprehensive and updated overview of the engineering aspects of the (U)HPH process, specifically focusing on (U)HPH modification of food components such as polysaccharides, proteins, and bioactive compounds. A detailed description of the potential applications in food products beyond microbial inactivation is also included.

Effects of β-cyclodextrin, whey protein, and soy protein on the thermal and storage stability of anthocyanins obtained from purple-fleshed sweet potatoes

The effects of β-cyclodextrin (β-CD), whey protein (WP), and soy protein (SP) on the color loss and degradation of anthocyanins in purple-fleshed sweet potato anthocyanin extracts (PFSPAEs) during thermal treatment and shelf-life storage in model beverage systems by performing chromaticity, degradation kinetics, and principal component analysis. Results showed that WP and SP improved the thermal stability of the PFSPAE, but WP accelerated the color loss of the extract. However, the addition of 25 mg/L SP improved the color and thermal stability of the anthocyanins when heated at 100 °C for 30 min. With regard to the shelf-life storage, the addition of SP and WP showed non-significant effect on the storage stability of the PFSPAE. However, the addition of 2500 mg/L β-CD significantly improved the storage stability of the PFSPAE. In summary, our findings provide useful information on improving the thermal and storage stability of PFSPAEs in beverage systems using food biopolymers.