Browsing by Person "Lonchamp, Julien"

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Anthocyanin-rich extracts from purple and red potatoes as natural colourants: Bioactive properties, application in a soft drink formulation and sensory analysis
(Elsevier, 2020-11-03) Sampaio, Shirley L.; Lonchamp, Julien; Dias, Maria Inês; Liddle, Catriona; Petropoulos, Spyridon A.; Glamočlija, Jasmina; Alexopoulos, Alexios; Santos-Buelga, Celestino; Ferreira, Isabel C. F. R.; Barros, Lillian
Aqueous extracts from seven coloured potato varieties (three red-fleshed, three-purple fleshed, and one marble-fleshed genotype) were studied for their anthocyanin content, in vitro biological activities, colouring properties and their potential application in the food industry. Acylated glycosides or pelargonidin and petunidin aglycones were identified as the main anthocyanin forms in the red and purple varieties, respectively. The total anthocyanin content among varieties ranged from 478.3 to 886.2 mg/100 g extract. All the extracts presented in vitro antioxidant, antibacterial and antifungal activities, whereas no toxic effects were detected. Finally, two selected extracts were tested as colourants in a soft drink formulation and presented suitable sensory profiles as well as high colour stability during a 30-day shelf-life when compared with the commercial colourant E163. Therefore, the tested extracts could be used as natural food colourants and considered for substituting the existing synthetic colouring agents.
Electrostatic complexes of whey protein and pectin as foaming and emulsifying agents
(2018-01-09) Oduse, Kayode; Campbell, Lydia; Lonchamp, Julien; Euston, Stephen R.
Five types of electrostatic complex (macromolecular complexes, core-shell particles, and mixed homogeneous particles) were formed between whey protein (whey protein concentrate [WPC]) and pectin. By controlling the thermal treatment, composition, and order of mixing, it was possible to produce complexes that for the same biopolymer concentration gave differing functional properties. All protein-pectin complexes showed higher foaming ability and stability than native or heated WPC without pectin. Native WPC had higher emulsifying ability than protein-pectin complexes but exhibited the lowest emulsion stability. Ingredients based on such ideas might offer the food manufacturer greater control over food structure, stability, and organoleptic properties.
Experimental induction of paromomycin resistance in antimony-resistant strains of L. donovani: Outcome dependent on in vitro selection protocol
(PLOS, 2012-05-29) Hendrickx, Sarah; Inocêncio da Luz, Raquel Andrea; Bhandari, Vasundhra; Kuypers, Kristel; Shaw, Craig D.; Lonchamp, Julien; Salotra, Poonam; Carter, Katharine; Sundar, Shyam; Rijal, Suman; Dujardin, Jean-Claude; Cos, Paul; Maes, Louis
Paromomycin (PMM) has recently been introduced for treatment of visceral leishmaniasis in India. Although no clinical resistance has yet been reported, proactive vigilance should be warranted. The present in vitro study compared the outcome and stability of experimental PMM-resistance induction on promastigotes and intracellular amastigotes. Cloned antimony-resistant L. donovani field isolates from India and Nepal were exposed to stepwise increasing concentrations of PMM (up to 500 µM), either as promastigotes or intracellular amastigotes. One resulting resistant strain was cloned and checked for stability of resistance by drug-free in vitro passage as promastigotes for 20 weeks or a single in vivo passage in the golden hamster. Resistance selection in promastigotes took about 25 weeks to reach the maximal 97 µM inclusion level that did not affect normal growth. Comparison of the IC50 values between the parent and the selected strains revealed a 9 to 11-fold resistance for the Indian and 3 to 5-fold for the Nepalese strains whereby the resistant phenotype was also maintained at the level of the amastigote. Applying PMM pressure to intracellular amastigotes produced resistance after just two selection cycles (IC50 = 199 µM) compared to the parent strain (IC50 = 45 µM). In the amastigote-induced strains/clones, lower PMM susceptibilities were seen only in amastigotes and not at all in promastigotes. This resistance phenotype remained stable after serial in vitro passage as promastigote for 20 weeks and after a single in vivo passage in the hamster. This study clearly demonstrates that a different PMM-resistance phenotype is obtained whether drug selection is applied to promastigotes or intracellular amastigotes. These findings may have important relevance to resistance mechanism investigations and the likelihood of resistance development and detection in the field.
Extraction of an emulsifying agent from the cellulose-based filtration aid of cold-pressed rapeseed oil
(Elsevier, 2025-01-18) Lonchamp, Julien; Euston, Stephen R.
This study aimed to extract an emulsifying agent from the cellulose-based filtration aid of cold-pressed rapeseed oil. This material is currently a low-value stream but contains phospholipids retained during filtration and proteins from residual seed peel and pulp particles. A range of two-step extraction methods were assessed, with oil removal using diethyl ether (DE) or petroleum ether followed by chloroform-methanol (CM) extraction (2:1, 3:2 or 5:4 ratios) or the reversed order. Emulsions prepared with the DE/CM3:2 extract displayed the highest emulsifying activity and stability indexes (35.52 m2/g and 2,045.18 min) and similar small mean oil droplet sizes (3 μm) to those of whey protein concentrate emulsions. A range of extracted compounds contributed to the DE/CM3:2 functionality, including napins, cruciferins and phospholipids. This study demonstrated for the first time the potential to upcycle this co-product by recovering emulsifying agents. Future studies will focus on optimising the extraction process and yield.
Foaming, emulsifying and rheological properties of extracts from a co-product of the Quorn fermentation process
(Springer, 2019-05-24) Lonchamp, Julien; Clegg, Paul; Euston, Stephen R.
This study assessed the functional profile (foaming, emulsifying and rheological properties), proteomic and metabolomic composition of a naturally foaming and currently unexploited co-product (centrate) from the Quorn fermentation process. Due to the low environmental footprint of this process the centrate is a potential source of sustainable functional ingredients for the food industry. A range of fractions were isolated from the centrate via successive ultrafiltration steps. The retentate 100 (R100) fraction, which was obtained following a 100 kDa ultrafiltration, displayed good foaming, emulsifying and rheological properties. R100 solutions and oil-in-water emulsions displayed high viscosity, while R100 solutions and hydrogels showed high viscoelasticity. R100 foams displayed high stability while oil-in-water R100 emulsions showed small and stable oil droplet size distributions. Large mycelial aggregates were reported in R100 solutions and gels, correlating with their high viscosity and viscoelasticity. A dense mycelial network was observed in R100 foams and contributing to their stability. In parallel tensiometry measurements highlighted the presence of interfacially active molecules in R100 which formed a rigid film stabilising the oil/water interface. A number of functional metabolites and proteins were identified in the centrate, including a cerato-platanin protein, cell membrane constituents (phospholipids, sterols, glycosphingolipids, sphingomyelins), cell wall constituents (chitin, chitosan, proteins), guanine and guanine-based nucleosides and nucleotides. This study highlighted the potential of functional extracts from the Quorn fermentation process as novel ingredients for the preparation of sustainable food products and the complex and specific nature of the centrate’s functional profile, with contributions reported for both mycelial structures and interfacially active molecules.
Functional enhancement of whey protein concentrate and egg by partial denaturation and co-processing
(Elsevier, 2022-07-14) Lonchamp, Julien; Clegg, P.S.; Euston, S.R.
This study investigated functional enhancement strategies for whole egg (WE), egg yolk (EY) and whey protein concentrate (WPC) with a view to reducing their required concentrations in formulations and the resulting environmental footprint. WE and EY underwent a combined phospholipase PLA2 and controlled heat treatment (WE2 and EY2) while WPC was partially-denatured via controlled heating (pdWPC). WE2 and EY2 samples were mixed with pdWPC and were also control-heated (h) with WPC. WE2-WPC(h) foams proved more stable than their untreated controls. WE2, EY2 and EY2-pdWPC showed higher emulsifying properties than their untreated controls. pdWPC, EY2 and EY2-WPC(h) hydrogels proved more viscoelastic than their untreated controls. EY2 and EY2-WPC(h) displayed an additional 45 kDa protein band, which could correspond to surface-active apoproteins released from lipoproteins. This work highlighted the potential to enhance WE, EY and WPC functionality via combined partial denaturation treatments and via synergy between WPC and WE or EY when co-processed.
Functional fungal extracts from the Quorn fermentation co-product as novel partial egg white replacers
(Springer, 2019-11-13) Lonchamp, Julien; Akintoye, M.; Clegg, P. S.; Euston, S. R.
The production of mycoprotein biomass by Marlow Foods for use in their meat alternative brand Quorn is a potential source of sustainable alternatives to functional ingredients of animal origin for the food industry. The conversion of this viscoelastic biomass into the Quorn meat-like texture relies on functional synergy with egg white (EW), effectively forming a fibre gel composite. In a previous study we reported that an extract (retentate 100 or R100) obtained from the Quorn fermentation co-product (centrate) via ultrafiltration displayed good foaming, emulsifying and rheological properties. This current study investigated if a possible similar synergy between EW and R100 could be exploited to partially replace EW as foaming and/or gelling ingredient. The large hyphal structures characteristic of R100 solutions were observed in EW-R100 mixtures, while EW-R100 gels showed dense networks of entangled hyphal aggregates and filaments. R100 foams prepared by frothing proved less stable than EW ones, however a 75/25 w/w EW-R100 mixture displayed a similar foam stability to EW. Simlarly R100 hydrogels proved less viscoelastic than EW ones, however the viscoelasticity of gels prepared with 50/50 w/w and 75/25 w/w EW-R100 proved similar to those of EW gels while 75/25 w/w EW-R100 gels displayed similar hardness to EW ones. Both results highlighted a functional synergy between the R100 material and EW proteins. In parallel tensiometry measurements highlighted the presence of surface-active material in EW-R100 mixtures contributing to their high foaming properties. These results highlighted the potential of functional extracts from the Quorn fermentation process for partial EW replacement as foaming and gelling agent, and the complex nature of the functional profile of EW-R100 mixtures, with contributions reported for both hyphal structures and surface-active material.
Identification of volatile quality markers of ready-to-use lettuce and cabbage
(Elsevier, 2009-05-20) Lonchamp, Julien; Barry-Ryan, Catherine; Devereux, Michael
Volatile emission changes of ready-to-use vegetables directly result from minimal processing and can reflect the sensory changes occurring in the product. Based on the detection of key volatile compounds, novel on-line and consumer quality-monitoring methods can be developed. The aim of this study was to identify volatile biomarkers for a range of leafy green ready-to-use vegetables (Butterhead and Iceberg lettuce and Irish York cabbage). Headspace volatile compounds were monitored using gas chromatography/mass spectrometry (GC/MS). The sensory quality of the products was evaluated at days 1, 7 and 14 using sensory and analytical measurements. Changes of volatile concentrations and sensory attributes were statistically correlated. The main quality markers identified for active modified atmosphere packaged (MAP) Butterhead lettuce were: 2-ethyl-1-hexanol, cis-3-dodecene, 4-ethylbenzaldehyde, acetocinnamone, β-elemene, 1-chlorododecane, dimethylethylphenol, ester pentanoic acid and thio-amino-butanamide. The main indicators of freshness were dimethylethylphenol and ester pentanoic acid, while the main quality loss markers were cis-3-dodecene and β-elemene.
Impact of plant essential oils on microbiological, organoleptic and quality markers of minimally processed vegetables
(Elsevier, 2008-10-31) Gutierrez, Jorge; Bourke, Paula; Lonchamp, Julien; Barry-Ryan, Catherine
The objectives of this study were to evaluate the efficacy of plant essential oils (EOs) for control of the natural spoilage microflora on ready-to-eat (RTE) lettuce and carrots whilst also considering their impact on organoleptic properties. Initial decontamination effects achieved using EOs were comparable to that observed with chlorine and solution containing oregano recorded a significantly lower initial TVC level than the water treatment on carrots (pb0.05). No significant differences were found between the EO treatments and chlorine considering gas composition, color, texture and water activity of samples. The sensory panel found EO treatments acceptable for carrots throughout storage, while lettuce washed with the EO solutions were rejected for overall appreciation by Day 7. Correlating microbial and sensory changes with volatile emissions identified 12 volatile quality markers. Oregano might be a suitable decontamination alternative to chlorine for RTE carrots, while the identification of volatile quality markers is a useful complement to sensory and microbiological assessments in the monitoring of organoleptic property changes and shelf-life of fresh vegetables. Industrial relevance: There is industrial demand for natural alternatives to chlorine, which is commonly used for decontamination of fresh produce but which has limitations with respect to antimicrobial efficacy and possible formation of carcinogenic compounds in water. Plant essential oils have proven antimicrobial and other bioactive properties, however their usefulness in foods can be mitigated by their high sensory impact. This study examined the application of EOs for fresh produce decontamination addressing control of spoilage microflora and improving shelf-life characteristics whilst also considering the impact on organoleptic properties. The effectiveness of oregano as a decontamination treatment was comparable with that of chlorine. Carrot discs treated with the EO regimes were acceptable in terms of sensory quality and appreciation, therefore oregano could offer a natural alternative for the washing and preservation of fresh produce. Combining EOs with other natural preservatives might minimize doses and reduce the impact on organoleptic properties of fresh vegetables.
In vitro selection of miltefosine resistance in promastigotes of Leishmania donovani from Nepal: Genomic and metabolomic characterization
(John Wiley & Sons, 2015-12-29) Shaw, C. D.; Lonchamp, Julien; Downing, T.; Imamura, H.; Freeman, T. M.; Cotton, J. A.; Sanders, M.; Blackburn, G.; Dujardin, J. C.; Rijal, S.; Khanal, B.; Illingworth, C. J. R.; Coombs, G. H.; Carter, K. C.
In this study, we followed the genomic, lipidomic and metabolomic changes associated with the selection of miltefosine (MIL) resistance in two clinically derived Leishmania donovani strains with different inherent resistance to antimonial drugs (antimony sensitive strain Sb‐S; and antimony resistant Sb‐R). MIL‐R was easily induced in both strains using the promastigote‐stage, but a significant increase in MIL‐R in the intracellular amastigote compared to the corresponding wild‐type did not occur until promastigotes had adapted to 12.2 μM MIL. A variety of common and strain‐specific genetic changes were discovered in MIL‐adapted parasites, including deletions at the LdMT transporter gene, single‐base mutations and changes in somy. The most obvious lipid changes in MIL‐R promastigotes occurred to phosphatidylcholines and lysophosphatidylcholines and results indicate that the Kennedy pathway is involved in MIL resistance. The inherent Sb resistance of the parasite had an impact on the changes that occurred in MIL‐R parasites, with more genetic changes occurring in Sb‐R compared with Sb‐S parasites. Initial interpretation of the changes identified in this study does not support synergies with Sb‐R in the mechanisms of MIL resistance, though this requires an enhanced understanding of the parasite's biochemical pathways and how they are genetically regulated to be verified fully.
The major proteins of the seed of the fruit of the date palm (phoenix dactylifera l.): Characterisation and emulsifying properties
(Elsevier, 2015-11-11) Akasha, Ibrahim; Campbell, Lydia; Lonchamp, Julien; Euston, Stephen R.
Proteins were extracted from the seeds of the fruit of the date palm. Proteomic analysis and SDS-PAGE electrophoresis of the extracted proteome suggested it is composed predominantly of the storage proteins glycinin and β-conglycinin, although over 300 proteins were detected, 91 of which were identified with confidence. In terms of protein type, the largest numbers of proteins were associated, not unexpectedly, with metabolism and energy functions, which reflected the requirements of the germinating and growing embryonic plant. The emulsifying properties of the extracted proteins were determined. Date seed protein exhibited a lower emulsifying activity than either whey protein concentrate or soy protein isolate at each of the pH values tested. However, the stability of the emulsions produced with all three proteins was very similar at the different pH values. This combination of large emulsion droplet size and high emulsion stability properties suggested that the date proteins may adsorb as large protein oligomers.
Molecular simulation of partially denatured β-lactoglobulin
(Elsevier, 2023-04-29) Zhang, Zhuo; Arrighi, Valeria; Campbell, Lydia; Lonchamp, Julien; Euston, Stephen R.
The unfolding of β-lactoglobulin (β-lac) upon heating was comprehensively studied through molecular dynamics computer simulations. A β-lac molecule in the aqueous solution was firstly heated at 500 K for unfolding and then annealed at 300 K to collect stable conformations. There were five meta-stable conformations observed based on the Free Energy Landscape (FEL). The β-lac molecule was found to exhibit an open and extended conformation on heating followed by limited refolding upon cooling. The cysteine residues –SH121 and S–S66-160 in the most open conformation were located at the opposite ends of the β-lac molecule. This would favour the intermolecular –SH/S–S interchange reactions that are known to occur in β-lac as part of the inter-molecular aggregation process. Furthermore, the unfolding of the β-lac increased the hydrogen bond forming capacity between water molecules and the protein and between water molecules themselves. The interactions and the properties of the water molecules in the protein hydration shell also indicated that the hydration shell was stabilized by protein unfolding. However, it was found that the unfolding of β-lac increased diffusion of hydration water molecules, including those in the first hydration shell that interact more strongly with the protein. This may partly explain why unfolded proteins are more likely to aggregate even though there were more hydration water molecules protecting them. Such results provided more detailed information on the structure-functionality relationship of β-lac based on both the protein molecule and its hydration shell. This provides insight into how we can control the processing of proteins for desirable functional properties such as thickening and gelation, which are modified through protein-water interactions.
Mycoprotein as novel functional ingredient: Mapping of functionality, composition and structure throughout the Quorn fermentation process.
(2022-07-20) Lonchamp, Julien; Stewart, Kelly; Munialo, Claire D; Evans, Laurence; Akintoye, Muyiwa; Gordon, Susan; Clegg, Paul S; Willoughby, Nik; Euston, Stephen R
This study provides the first mapping of mycoprotein functionality, composition and structure throughout the Quorn fermentation process. The fermentation broth, RNA-reduced broth (RNA-broth), centrate and their centrifugation deposits and supernatants were characterised. The broth, RNA-broth and their deposits displayed high concentrations of fungal filaments, which contributed to their high gelling properties (with a 5,320 Pa elastic modulus reported for RNA-broth deposits gels). Foams prepared with RNA-broth and centrate supernatants via frothing exhibited high stability (380 min), with high concentrations of a foam-positive cerato-platanin reported in these samples. Emulsions prepared with the broth and broth supernatant showed high emulsifying activity and stability indexes (12.80 m /g and 15.84 mins for the broth supernatant) and low oil droplet sizes (18.09 µm for the broth). This study identified previously unreported gelling, foaming and/or emulsifying properties for the different Quorn streams, highlighting opportunities to develop novel sustainable alternatives to animal-derived functional ingredients using mycoprotein material. [Abstract copyright: Copyright © 2022 The Author(s). Published by Elsevier Ltd.. All rights reserved.]
Novel palm shortening substitute using a combination of rapeseed oil, linseed meal and beta-glucan
(Elsevier, 2024-06-19) Sampaio, Shirley L.; Chisnall, Timothy; Euston, Stephen R.; Liddle, Catriona; Lonchamp, Julien
This study investigated the potential of a novel sustainable ingredient composed of rapeseed oil, linseed meal and beta-glucan (PALM-ALT) to mimic palm shortening functionality in cake. The combined functional properties of linseed meal and beta-glucan led to stable semi-solid emulsion-gels (20–31 μm oil droplet size, 105–115 Pa.s viscosity and 60–65 Pa yield stress). PALM-ALT contained 25 and 88% less total and saturated fat than palm shortening, whilst PALM-ALT cakes contained 26 and 75% less total and saturated fat than the palm-based control. PALM-ALT cakes matched the flavour profile of the palm-based control, while rapeseed oil cakes tasted more sour and less sweet than the control (p < 0.05). PALM-ALT cakes proved less hard and more cohesive than the control (p < 0.05), with 100% of the consumer panel preferring PALM-ALT formulations. This study demonstrated the unique potential of PALM-ALT as healthier, sustainable and competitive alternative to palm shortening.
OE-4-1 Extraction and properties of protein extracted from fungal fermentations [abstract]
(Elsevier, 2025-07-07) Euston, S; Lonchamp, Julien; Stewart K, Munialo C; Willoughby, N
Properties of partially denatured whey protein products 2: Solution flow properties
(Elsevier, 2015-12-22) Zhang, Zhuo; Arrighi, Valeria; Campbell, Lydia; Lonchamp, Julien; Euston, Stephen R.
Partial denaturation of whey protein concentrates has been used to make protein powders with differing viscosity properties. PDWPC particles have been manufactured to have a range of aggregate sizes (3.3–17 μm) and structures (compact particle gel to open fibrillar gel). In solution the PDWPC samples show complex viscosity behaviour dependant on the size and morphology of the PDWPC aggregate particles. For the same protein content the compact particles have a lower viscosity than open, fibrillar particles. The viscosity also appears to depend on the surface structure of the particles, with particles of a similar size, but having a rougher surface giving higher viscosity than similar smooth particles. The viscosity of the WPC, MPWPC and PDWPC solutions are explained in terms of the postulated interactions between the protein aggregates in solution.
Properties of partially denatured whey protein products: Formation and characterisation of structure
(Elsevier, 2015-06-22) Zhang, Zhuo; Arrighi, Valeria; Campbell, Lydia; Lonchamp, Julien; Euston, Stephen R.
Partially denatured whey protein (PDWPC) products have been manufactured using a controlled heating process that allows control of the degree of denaturation of the whey proteins. This is assessed by following the change in free sulphydryl content of the protein as heating progresses. This allows the formation of soluble whey protein aggregates of diverse particle size and morphology. The PDWPC's have been made using different manufacturing conditions (temperature, pH, degree of denaturation) to give aggregated PDWPC powders with a degree of denaturation in the range 45–98% and particle size 3–17 μm. Particle size analysis, scanning electron microscopy and density analysis show that the particles have aggregated structures that range from compact, particulate gel-like to fibrillar phase-separated structures, with intermediate structures formed under some conditions. These structures are consistent with the known gel structures formed in whey protein concentrate gels. The structure of the PDWPC particles differs from that of microparticulated whey proteins. The possibility of using PDWPC's as ingredients tailored to the needs of food manufacturers is discussed.
Properties of partially denatured whey protein products: Viscoelastic properties
(Elsevier, 2018-02-07) Euston, Stephen R.; Lonchamp, Julien; Campbell, Lydia; Arrighi, V.; Zhang, Z.
Partially denatured whey protein products (PDWPC's) can be classified based on the viscoelastic properties of their solutions. Strain sweeps show that PDWPC-A and -B and microparticulated WPC (MPWPC) with compact, spherical aggregated particles exhibit a strong strain overshoot. PDWPC-C and -D, on the other hand, which have open, elongated porous particles show a weak strain overshoot. The concentration dependence of the elastic modulus G' in the linear viscoelastic region has a biphasic power law dependence with concentration for all protein products studied, except for WPC where G' is independent of protein concentration. Frequency sweeps suggest that MPWC solutions form a strong physical gel at all concentrations above 14% (w/w). PDWPC-A and -B form weak gels over the same concentration range. PDWPC-C and -D also form weak gels at 14% protein (w/w) but strong physical gels at higher concentrations. The frequency dependence of G' and G'' for all aggregated proteins show a power law dependence indicating fractal type structures. For all solutions above a critical concentration, the fractal dimensions span the range 1.6-2.3, indicating a range of gel network structures from open and diffuse to compact and dense. Adherence to the empirical Cox-Merz rule was observed in PDWPC-A, -C and -D at concentrations of 14 and 16% (w/w) protein, suggesting liquid-like behaviour. At higher protein concentrations the deviations from the Cox-Merz rule suggest more pronounced elasticity in the structure. For PDWPC-B, the behaviour is complex, with deviation from the Cox-Merz rule at low frequencies/shear rates, but correspondence at higher frequencies/shear rates at all concentrations. This indicates a frequency-dependent change from liquid-like behaviour over long timescale deformations, to a solid-like behaviour at short timescale deformations. MPWPC solutions of all concentrations do not follow the Cox-Merz rule, suggesting solid-like behaviour. The PDWPCs exhibit a complex rheological behaviour which suggests they could be versatile thickening, texturizing and fat replacement
Reformulation of Biscuit and Oatcake Products With Nutritional and Environmental Benefits Using a Novel Palm Shortening Substitute
(Wiley, 2025-08-28) Mora-Gallego, Hector; Craddock, Robert; Euston, Stephen R.; Liddle, Catriona; Lonchamp, Julien
This paper assessed the feasibility of replacing palm shortening with a novel sustainable ingredient composed of rapeseed oil, linseed meal, and beta-glucan (PALM-ALT) in hard-texture bakery products (biscuit and oatcake). There is currently no palm shortening alternative that is functional, sustainable, nutritionally-balanced, and competitive. The PALM-ALT ingredient was characterized by oil droplet size distribution, rheology, confocal microscopy, and scanning-electron microscopy, whilst the biscuits and oatcakes were profiled by sensory, texturometry, colorimetry, water activity, and moisture analyses. The PALM-ALT ingredient exhibited a stable emulsion-gel structure (32 µm oil droplet size, 62 Pa.s viscosity, 40 Pa yield stress). Linseed proteins contributed to the formation and stabilization of oil droplets, whilst linseed mucilage, oat beta-glucan, and aggregates of linseed proteins and/or beta-glucan (observed in the continuous phase) further stabilized the emulsion. Three formulations were prepared with either palm shortening, rapeseed oil, or PALM-ALT. PALM-ALT biscuits and oatcakes respectively showed an 86% and 75% saturated fat reduction in comparison with their palm-based control product. PALM-ALT products displayed similar sensory and instrumental profiles to their palm-based controls, whereas rapeseed oil formulations exhibited significantly different color, odor, and texture profiles than the controls (p < 0.05). Rapeseed oil biscuits showed a lower overall sensory quality than their palm-based control, whilst PALM-ALT oatcakes displayed a higher acceptability than the control and rapeseed oil products (p < 0.05). This study showed that PALM-ALT was able to replace palm shortening in hard-texture bakery formulations with maintenance of their sensory profiles, whilst providing nutritional and sustainability benefits.
Sonicated extracts from the Quorn fermentation co-product as oil-lowering emulsifiers and foaming agents
(Springer, 2020-02-01) Lonchamp, Julien; Akintoye, Muyiwa; Clegg, Paul; Euston, Stephen
This study assessed the impact of sonication on the structure and properties of a functional extract (retentate 100 or R100) from the Quorn fermentation co-product (centrate). In a previous study we reported that the R100 fraction displayed good foaming, emulsifying and rheological properties. Sonication of a R100 solution led to the breakdown of the large hyphal structures characteristic of this extract into smaller fragments. Foams prepared with sonicated R100 displayed a higher foaming ability than with untreated R100 and a high foam stability but lower than untreated R100 ones. Oil-in-water emulsions prepared with sonicated R100 displayed smaller oil droplet size distributions than with untreated R100. Confocal micrographs suggested that small fungal fragments contributed to the stabilisation of oil droplets. 50% oil-reduced R100 emulsions were prepared by mixing R100 emulsions (untreated or sonicated) with a sonicated R100 solution at a 1:1 ratio. Smaller oil droplet size distributions were reported for the oil-reduced emulsions. These results showed that the addition of small hyphal fragments or surface-active molecules and molecular aggregates released during sonication contributed to the formation and stabilisation of smaller oil droplets. This study highlighted the potential to modulate the structure, emulsifying and foaming properties of functional extracts from the Quorn fermentation co-product by sonication and the potential of these extracts as oil-lowering agents in emulsion-based products through the reduction of oil droplet size and their stabilisation.