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Item Emulsifying properties of hemp and whey protein complexes achieved by microparticulation(Elsevier Ltd, 2026-03-01) Ma S; Ye A; Singh H; Acevedo-Fani AHemp is a sustainable source of protein. However, the utilisation of commercial hemp protein (HP) is limited due to its poor functionality. This study provided a microparticulation method to produce hybrid microparticles by complexing HP and whey protein isolate (WPI), and investigated their emulsifying potential. The emulsions, composed of 10 % oil and 0.25–1.8 % protein (non-microparticulated or microparticulated HP/WPI), were produced and the impact of microparticulation on the emulsifying ability of HP/WPI was explored using static light scattering, CLSM, TEM and SDS electrophoresis analysis. The results showed that non-microparticulated HP/WPI stabilised emulsions exhibited preferential whey protein adsorption at the oil-water interface, leading to sufficient protein coverage at most protein concentrations (0.25–1.8 %) with relatively small droplet size (∼0.5 μm) and minimal flocculation. In contrast, in the 'emulsifier-poor' regime (0.25–1 %), microparticulated HP/WPI stabilised emulsions displayed larger droplet size with clear signs of bridging flocculation. However, when the protein concentration was sufficient (≥1.5 % protein), it reached a similar droplet size as that of non-microparticulated HP/WPI emulsion with minimal flocculation. Microparticulation increased HP loading at the interface, while emulsions stabilised by non-microparticulated HP/WPI showed less HP adsorption. Transmission electron microscopy further confirmed the microparticle coverage. Moreover, the heat stability of microparticulated HP/WPI stabilised emulsions increased, compared with non-microparticulated HP/WPI. These findings highlight the potential of microparticulated HP/WPI systems in the application of emulsification and enhance HP applications in the food industry.Item Large-scale synthesis of N-doped carbon capsules supporting atomically dispersed iron for efficient oxygen reduction reaction electrocatalysis(Elsevier B.V. on behalf of Nankai University, 2022-05-17) Yang H; Liu Y; Liu X; Wang X; Tian H; Waterhouse GIN; Kruger PE; Telfer SG; Ma SThe large-scale synthesis of platinum-free electrocatalysts for the oxygen reduction reaction (ORR) remains a grand challenge. We report the large-scale production of stable and active ORR electrocatalysts based on iron, an earth-abundant element. A core–shell zeolitic imidazolate framework–tannic acid coordination polymer composite (ZIF-8@K-TA) was utilized as the catalyst precursor, which was transformed into iron atoms dispersed in hollow porous nitrogen-doped carbon capsules (H-Fe-Nx-C) through ion exchange and pyrolysis. H-Fe-Nx-C features site-isolated single-atom iron centers coordinated to nitrogen in graphitic layers, high levels of nitrogen doping, and high permeability to incoming gases. Benefiting from these characteristics, H-Fe-Nx-C demonstrated efficient electrocatalytic activity (E1/2 = 0.92 V, vs. RHE) and stability towards the ORR in both alkaline and acidic media. In ORR performance, it surpassed the majority of recently reported Fe-N-C catalysts and the standard Pt/C catalyst. In addition, H-Fe-Nx-C showed outstanding tolerance to methanol.Item Heat-induced interactions between microfluidized hemp protein particles and caseins or whey proteins(Elsevier Ltd, 2025-01) Ma S; Ye A; Singh H; Acevedo-Fani AThe rising demand for sustainable proteins leads to increased interest in plant proteins like hemp protein (HP). However, commercial HP's poor functionality, including heat aggregation, limit its use. This study explored the heat-induced interactions of hemp protein particles (HPPs) with milk proteins, specifically whey proteins and caseins. Using various analysis techniques-static light scattering, TEM, SDS electrophoresis, surface hydrophobicity, and free sulfhydryl content-results showed that co-heating HPPs with whey protein isolate (WPI) or sodium caseinate (NaCN) at 95 °C for 20 min reduced HPPs aggregation. HPPs/WPI particles had a d4,3 of ∼3.8 μm, while HPPs/NaCN were ∼1.9 μm, compared to ∼27.5 μm for HPPs alone. SDS-PAGE indicated that whey proteins irreversibly bound to HPPs, through disulfide bonds, whereas casein bound reversibly, possibly involving the chaperone-like property of casein. This study proposes possible mechanisms by which HPPs interact with milk proteins and impact protein aggregation. This may provide opportunities for developing hybrid protein microparticlesItem Heat-induced interactions of hemp protein particles formed by microfluidisation with β-lactoglobulin(Elsevier Ltd, 2024-07-01) Ma S; Acevedo-Fani A; Ye A; Singh HThis study explored the effect of microfluidization on the dispersibility of hempseed protein (HP) and the interactions of microfluidised HP particles with β-lactoglobulin (β-lg) after heat treatment. Microfluidization increased the dispersible protein fraction from 10% (non-microfluidised) to a maximum of 58% (200 MPa, 6 passes) in HP dispersions. Dispersible HP particles were within the micro-sized range (d4,3 ≤ 2 μm) after microfluidization. Heat treatment (95 °C, 10–60 min) of HP particles with β-lactoglobulin (β-lg) induced protein association by sulphydryl-disulphide exchange reactions; β-lg association with HP particles initiated within the first 20 min. Additionally, the particle size (d4,3) values of co-heated HP particles with β-lg were significantly smaller than those found in HP particle dispersions heated alone, results that were in line with microscopy analysis. This suggests that β-lg could have restricted HP particle aggregation. In conclusion, combining microfluidization and heat treatment could offer a venue to modify the physical properties of plant/milk protein mixtures.Item Structural and Physicochemical Characteristics of Oil Bodies from Hemp Seeds (Cannabis sativa L.)(MDPI (Basel, Switzerland), 2021-11-26) Garcia FL; Ma S; Dave A; Acevedo-Fani A; Fiorini DThe structural and physicochemical characteristics of oil bodies from hemp seeds were explored in this study. Oil bodies from several plant-based sources have been previously studied; however, this is the first time a characterisation of oil bodies from the seeds of industrial hemp is provided. The morphology of oil bodies in hemp seeds and after extraction was investigated using cryo-scanning electron microscopy (cryo-SEM), and the interfacial characteristics of isolated oil bodies were studied by confocal laser scanning microscopy (CLSM). Proteins associated with oil bodies were characterised using sodium dodecyl sulphate polyacrylamide gel electrophoresis (SDS-PAGE). The effect of pH and ionic strength on colloidal properties of the oil bodies was investigated. Oil bodies in hemp seeds appeared spherical and sporadically distributed in the cell, with diameters of 3 to 5 μm. CLSM images of isolated oil bodies revealed the uniform distribution of phospholipids and proteins at their interface. Polyunsaturated fatty acids were predominant in the lipid fraction and linoleic acid accounted for ≈61% of the total fatty acids. The SDS-PAGE analysis of washed and purified oil bodies revealed major bands at 15 kDa and 50-25 kDa, which could be linked to membrane-specific proteins of oil bodies or extraneous proteins. The colloidal stability of oil bodies in different pH environments indicated that the isoelectric point was between pH 4 and 4.5, where oil bodies experienced maximum aggregation. Changes in the ionic strength decreased the interfacial charge density of oil bodies (ζ-potential), but it did not affect their mean particle size. This suggested that the steric hindrance provided by membrane-specific proteins at the interface of the oil bodies could have prevented them from flocculation at low interfacial charge density. The results of this study provide new tertiary knowledge on the structure, composition, and colloidal properties of oil bodies extracted from hemp seeds, which could be used as natural emulsions or lipid-based delivery systems for food products.