Structured fats like emulsion gels and bigels have emerged as promising animal fat substitutes for plant-based meat analogs. This study investigated the printability, rheological behavior, and interfacial compatibility of emulsion gels and bigels in combination with pea protein isolate (PPI) for extrusion-based single- and multi-material dual and coaxial 3D food printing (3DFP). Rheological analysis confirmed that despite having both systems exhibiting shear-thinning and thixotropic behavior, bigels demonstrate higher mechanical strength (G’ = 1000 Kpa vs 10 Kpa) and structural integrity (yield stress = 500 Pa vs 200 Pa). These properties translated into better print fidelity, with bigels maintaining defined structures across a range of temperatures (30–60 °C) in single-material 3DFP while emulsion gels were prone to phase separation, deformation and collapsing. In multi-material 3DP with PPI, bigels consistently demonstrated clear material separation, forming distinct core-shell structures in coaxial setups as well as maintaining well-defined, evenly distributed phases in dual extrusion. In contrast, emulsion gels exhibited smearing, irregular distribution, and poor interfacial definition in both setups, indicating weaker phase stability and compatibility with the protein matrix. Confocal laser scanning microscopy confirmed better interfacial phase boundaries between bigels and PPI, aligning with rheological and printing outcomes. In conclusion, bigels show high promise as multi-functional structuring agents and fat substitutes in multi-material 3DFP, while emulsion gels require further optimization to enhance their print performance and material compatibility

Side streams rich in irregular and deformable plant particles represent an untapped resource for sustainable food innovation. Pea hull fibres are an example of such underutilized, but increasing side stream material, whose functional limitation require targeted modification. In this study, we present a combined strategy using mechanical shearing and pectate lyase enzymatic treatment to enhance the functionality of pea hull fibres. This dual treatment alters their physicochemical properties, leading up to increase in their water retention capacity (WRC) and a shift in composition and microstructure revealed by optical microscopy. Enzymatic degradation of pectin improved water absorption and swelling ability, which translated into an increase in the viscosity of pea hull fibre suspensions. Importantly, we explore the rheological behaviour across an extended pea hull concentration range and identify three distinct regimes (dilute, intermediate and concentrated). These transitions were successfully captured and predicted using soft particle rheological models, demonstrating for the first time, the applicability of the models on suspensions based on pea hull fibres, as well as a prediction framework for pea hull fibre suspensions. Our findings show that mathematical models developed for soft plant particles can be used to predict suspension behaviour of pea hull fibres and establish a scalable approach to valorise plant-based side streams into high-performance functional ingredients

In plant-based products made to mimic meat it is sought after to include fat to enhance flavor and texture based on healthy plant-based oils. Oleogels have gained interest as way of structuring oils. However, understanding how the crystalline network affects long-term stability and oil mobility remains limited. In this study, rapeseed oil oleogels containing 10 % (w/w) of either candelilla wax, beeswax, or rice bran wax were investigated. We combined low-strain rheo-microscopy, differential scanning calorimetry (DSC), and fluorescence recovery after photobleaching (FRAP) to explore the evolution of microstructure, thermal transitions, viscoelastic properties, and local oil diffusion – an approach not previously applied to wax-based oleogels. Candelilla wax formed a dense homogenous network with small crystals and beeswax had longer needle-like aggregated structures. Both candelilla and beeswax showed one crystallization peak in DSC and a sharp increase in storage modulus during rheo-microscopy explained by their network structure. Rice bran wax had a mixture of larger spherulite structures and smaller crystals. Two distinct crystallization events were observed in DSC and rheo-microscopy for rice bran wax corresponding to the formation of large spherulites and subsequently smaller interspersed crystals. FRAP showed that candelilla wax with its dense homogenous structure had the largest retardation rate independently of observation region. The diffusion in the crystal region was fastest in the rice bran wax which indicates a loosely packed crystal structure in the spherulites

This study investigated how fractionation method (dry fractionated (PPC) vs. wet fractionated (PPI)) affects pea protein 3D printability and rheological behavior at 10–50 wt.%. The potential of preheating and hydrocolloid addition (carrageenan, pectin, and xanthan gum) in enhancing their 3D printability, texture and microstructure was also evaluated. PPI alone showed good printability at 30 wt.%, while PPC remained unprintable even at 50 wt.% due to fiber-induced network disruption and low viscosity. However, PPC’s printability was restored at 40 wt.% through preheating and hydrocolloid addition. PPC and PPI responded very differently to hydrocolloids: pectin improved 3D printing resolution for PPI but weakened post-steaming texture, while in PPC, only pectin provided printability without adversely affecting texture. Overall, PPI demonstrated inherent 3D printability while PPC required modification to achieve comparable performance. Hydrocolloid functionality was protein-type specific, and successful 3D printing of pea protein requires tailored formulation strategies depending on the fractionation method

Alternative protein sources such as seaweed can help relieve the pressure on land-based protein supply. This proof-of-concept study developed an extraction method to recover soluble and lipophilic proteins from the seaweed Ulva fenestrata. The method consisted of processing U. fenestrata with 0.1–0.5 % aqueous Triton X-114 solution and reprocessing the pellet with an alkaline aqueous solution. Then, the solubilized proteins were precipitated via acidification. The new method extracted 3.4-times more protein, measured as total amino acids, compared to the control with two alkaline aqueous extraction cycles. Triton disrupted the chloroplasts and likely solubilized lipophilic membrane proteins as supported by microstructure and polypeptide pattern analysis. Triton-derived protein extracts contained lipids inside the precipitates/aggregates and were richer in fatty acids typical of photosynthetic membranes. The higher extraction yields are proposed to result from membrane charge neutralization upon acidification, triggering interactions between the membrane lipids and their subsequent precipitation with the lipophilic membrane protein. 

Development of satisfying plant based (PB) meat analogues could be expedited through better understanding of the sensorial drivers of hedonic (dis)liking. To address this, here six commercially available PB chicken analogues and a chicken breast reference are evaluated. Consumers (N = 105) report hedonic liking (appearance, aroma, taste/flavour, texture, and overall), sensorially profile the samples with rate-all-that-apply (RATA) and just-about-right (JAR) scales and describe what they like and dislike about the tasted samples in their own words (free-text responses). The samples are also characterized instrumentally: microscopy to visualize the microstructure and cyclic compression testing to quantify key mechanical properties (maximum true stress, Young's modulus, and compressive energy). The sensory space is explored with principal component analysis and penalty analysis; associations between the modalities of liking and how these may determine overall liking is assessed using Bayesian network analysis; and multiple regression with Bayesian inference is used to contrast liking across samples and identify the drivers of (dis)liking within each hedonic modality. Chicken is preferred across all hedonic modalities, while samples made of mycoprotein are liked most of the PB samples. Drivers of liking are detected for all modalities except appearance. The drivers of texture liking include higher perceived tenderness and juiciness, the latter of which is also inversely correlated with Young's modulus on the first compression cycle. The free-text responses suggest that consumers readily recognized the chicken sample. That sensory responses reflect both the intrinsic properties of products (bottom-up) and cognitive (top-down) aspects, including familiarity, is thus discussed.

Protein extraction from wheat bran is challenging due to its multi-layer and fiber-rich structure. Here, opening aleurone cells, via dry and wet milling, their combination and a novel ultrafine milling, and its effect on wheat bran’s protein recovery using the alkaline solubilization/isoelectric precipitation and protein structure, functionality, and phytate content were investigated. Wet milling and ultrafine milling improved protein recovery and purity but only ultrafine milling reduced bran particle size to the aleurone cells and exposed their structure. Despite this, ultrafine milling did not significantly increase protein yield compared to wet milling, which partially opened the aleurone cells, meaning that opening the cells per se is not enough for extracting their protein. Proteins extracted with the aid of ultrafine milling had smaller particle sizes with significantly better water solubility (>2-fold) and rheological properties. Both wet milling and ultrafine milling significantly improved the removal of phytate during the wet fractionation process. Altogether, optimizing milling techniques offers a promising path to enhance accessibility to wheat bran proteins and their quality if carefully fine-tuned but other assistant technologies are necessary for boosting the recovery of the released protein from aleurone cells. 

Dietary fibre intake is essential for all human beings and has been correlated to beneficial health effects. Pea hull fibres (PF) are generally seen as a side stream during extraction of protein and starch from yellow pea but could be used in various food products to boost fibre content. In this study, the thermal treatment of pea hull fibres was investigated in terms of physicochemical properties and in vitro colonic fermentation. The PF that was subjected to heating showed an increase of fibres solubilised in the liquid and particle size. Results also showed that viscosity and storage modulus increased with thermal treatment, possibly due to the swelling of the PF. The pea fibre was readily fermentable based on total gas production and pH. However, the susceptibility to fermentation of PF did not increase with thermal treatment. Total gas production and short chain fatty acid produced were similar independent of thermal treatment. Conclusively, heating of the PF resulted in increased ability to structure water suspension, owing to increased fibre particle size, but is not sufficient to increase short chain fatty acid production during colonic fermentation. To explain this, we propose that the changes in cell wall structure were not major enough to induce higher fermentability. 

The incorporation of fibre into pea protein matrices influences their microstructure, yet our understanding of their gut fermentability remains unexplored. In this study, dietary fibres and protein from yellow pea were investigated for their physico-chemical properties and impact on in vitro colonic fermentation using human inoculum. Pea fibre and pea protein blends were studied at different pH and after thermal treatment at 95 °C for 30 min with oscillatory rheology, static light scattering and confocal laser scanning microscopy. The effect on in vitro colonic fermentation was evaluated measuring gas production, ammonia, and short chain fatty acid (SCFA) production. Rheology indicated that during thermal treatment a firmer gel is formed close to the protein isoelectric point with a structure characterised by aggregation, but less particle swelling compared to other pH. Addition of fibre led to higher storage modulus (G′), with the fibre dominating the rheological properties. Fermentation of samples containing protein led to higher levels of ammonia and SCFA compared to only fibres. Blends produced higher amounts of valerate, i-valerate and caproate, and lower amounts of ammonia. Reduced fermentation of proteins in the presence of fibres was also reflected in a more intact microstructure of the protein particles in the digesta. Although thermal treatment of blends caused particle swelling and induced gelation, only small differences could be discerned in the in vitro colonic fermentation outcomes. Our results highlight that potentially harmful fermentation products from protein, such as ammonia, were reduced in the presence of pea hull fibre. 

The relationship between hemolysis and lipid oxidation was explored in red blood cell (RBCs)-spiked washed cod mince (WCM). At pH 6.8 and 3 ± 1 °C, intact RBCs (71 µM Hb) delayed lipid oxidation by 1 day compared to WCM with partly or fully lysed RBCs which oxidized immediately. Intact RBCs also lowered peak peroxide value (PV) and thiobarbituric acid reactive substances (TBARS) with up to 59.5% and 48.1%, respectively. Adding 3% (v/w) blood plasma to RBC-spiked WCM delayed the lipid oxidation onset from 1 to 3–4 days without delaying hemolysis. At pH 6.4 the oxidation onset in RBC-WCM was the same as for pH 6.8 while at pH 7.2–7.6 lipid oxidation was suppressed for 7 days. Micrographs revealed RBC-lysis from day 2 at pH 6.4 but at pH 7.6, RBC stayed intact for ≥ 7 days. Thus, assuring presence of plasma-derived antioxidants and/or elevating muscle pH to avoid hemolysis can aid valorization of blood rich underutilized fish raw materials.