The 17th International
Hydrocolloids Conference

Program Friday

Lecture Hall   |   |  
 Time      
  Session Chair: Doug Goff    
 8:40- 9:20 P6-246 Lingyun Chen Design of protein-based hydrocolloids for healthy food and biomaterial applications    
 9:20- 10:00 P7-244 Alejandra Acevedo-Fani Exploring hempseed cellular components for the next-gen food innovations    
10:00-10:30 Break Break Break
  Session Chair: David Everett Session Chair: Qi Wang  
10:30-11:00 I11-243 Skelte G. Anema, The magic of milk proteins Session Chair: Qi Wang (11:00-12:00 for C64-C66)  
11:00-11:20 C61-229. Decoding The A2 Dairy Dilemma: Scientific Discovery Meets Industry Application C64-258 Encapsulation of Algal Omega-3 Fatty Acids Using Functional Hydrocolloids for Targeted Delivery in Plant-Based food alternatives
11:20-11:40 C62-122. Effect of high-intensity ultrasound on physicochemical, structural, and functional properties of bovine milk, goat milk, camel milk, and their mixtures C65-211. Lubricity and structure response of human saliva pellicle to the dairy-saliva protein interaction and correlation with sensory perception
11:40-12:00 C63 -129. Introducing Spices to milk and their effects in gelation of milk systems C66-176. How measuring conditions affect the compression loss related to juiciness in plant-based burgers
12:00-13:00 Lunch Lunch Lunch
 Time      
  Session Skelte Anema Session Youling Xiong Session Qingbin Guo
13:00-13:20 C67-257 Zheng Pan Heat-set gelation of milk-isolated and recombinant β-LG C74-106. The effect of polyphenol-protein interactions on the pasting viscosity of purple waxy rice C81 -151. Interfacial Activity of Fucoidan for Enhancing its Bioactivity
13:20-13:40 C68-169. Investigation of the physical properties and microstructure in hybrid processed cheese formulated with plant protein ingredients and rennet casein C75-112. Effectiveness of alternative polymer binders for use in toothpastes C82-159. A tale of two biopolymers: the role of hemicellulose and lignin in the interfacial activity of birch glucuronoxylans
13:40-14:00 C69-127. Investigation of physicochemical, structural and nutritional properties of malted milk powders enriched with germinated cereals and pulses C76-180. New Zealand’s hide and skin co-products: an old dog ready for new tricks? C83-188. Standardised analytical methods for the analysis of plant-based milk products' emulsion components
14:00-14:20 C70-139. Physical, Chemical and Functional Properties of Yoghurts Enriched with Cooked Arrowroot and Potato Flour. C77-143. Valorising side streams: Properties of legume dry and wet fractionation by-products C84-116. Concentration-Dependent Behaviour of Sunflower Oleosomes At The Air-Water Surface
14:20-14:40 C71-132. β-lactoglobulin from precision fermentation for improved heat stability C78-164. Achieving in-vitro tablet breakup by spray drying different additives with caffeine or physical mixing and the connection between breakup, mass transfer and texture in digestion C85-148. Role of hydrocolloids in the production of long-chain polyunsaturated fatty acids (LCPUFAs) oil encapsulated powders with potato protein
14:40-15:00 C72-144. Partial substitution of dairy protein with Spirulina protein in milk mimetic formulations: studies on physicochemical and techno-functional properties C79-177. Effect of composition, water content and citric acid on the foam formation and foaming properties of yellow pea and black Beluga lentil purees C86-155. Camel milk at the air-water interface
1500-1510 Conference Close Conference Close Conference Close

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246Design of protein-based hydrocolloids for healthy food and biomaterial applications.

Lingyun Chen

Faculty of Agricultural, Life and Environmental Sci - Ag, Food & Nutri Sci Dept. University of Albert, Canada
The growing demand for sustainable and health-conscious food products has led to an increased interest in plant proteins as alternatives to animal proteins. However, developing stable and palatable protein-rich foods using plant proteins presents significant challenges. These challenges arise primarily from the structural limitations of plant proteins, which often exhibit lower solubility and functional properties due to their complex quaternary aggregates.

This presentation will explore the use of protein-based hydrocolloids as an effective strategy to address these challenges. It will focus on the design and development of protein fibrillar and particulate aggregates, as well as protein microgels, utilizing both bottom-up and top-down approaches. The impact of their morphology, size, and chemical characteristics on key functional properties—such as emulsifying, foaming, and gelling—will be discussed. Furthermore, the potential of protein-based hydrocolloids to enhance the stability, sensory attributes, and nutritional value of plant protein-based food products will be highlighted.

244Exploring hempseed cellular components for the next-gen food innovations

Dr. Alejandra Acevedo-Fani

Riddet Institute, Massey University. Private bag 11222, Palmerston North 4442, New Zealand
As the food industry faces the challenges of climate change and increasing consumer demand for clean-label products, the need for alternative ingredients is becoming increasingly urgent. This shift is driving the search for sustainable solutions to develop new food ingredients. Plant-based materials, particularly as replacements for animal-derived proteins and lipids, have become a focal point, leading to significant innovation across the sector.

Conventional methods of producing plant-based proteins and lipids often require large amounts of energy, water, and organic solvents for purification from plant cells. These extraction processes can disrupt the native structures in which proteins and lipids are naturally assembled, potentially overlooking the advantages these nature-assembled structures might offer as food ingredients.

For instance, seeds and grains store proteins and lipids within specialised organelles called protein bodies and oil bodies, which serve as energy sources during seed germination. These organelles can be isolated through mild extraction techniques and explored for various food applications. This approach may offer environmental benefits, though the impact of preserving the native structure on the components' functional properties, both technologically and nutritionally, remains not fully understood.

This presentation will cover our recent work on the isolation and characterization of protein and oil bodies from industrial hemp seeds, a sustainable crop that has been identified as relevant for New Zealand's agricultural future.

Keywords: sustainable ingredients, protein bodies, oil bodies, hempseed.

243The magic of milk proteins

Skelte G. Anema

Fonterra Research and Development Centre, Palmerston North, New Zealand
The functional properties of milk products are determined by the interactions of the proteins within the system. Interactions can be divided into groups such as: those naturally present (e.g. the assembly of the individual casein proteins with calcium phosphate to form casein micelles); process-induced interactions (e.g. interactions of denatured whey proteins with -casein/casein micelles) and spontaneous interactions (e.g. interaction of negatively charged casein micelles with positively charged whey proteins such as lactoferrin). The various interactions, and therefore the functional properties of the system, can be modified by changing the composition of the milk through the addition of individual milk proteins. This talk will present examples of the various types of interactions and how they are affected by changes to the protein composition of the milk at the time of processing. In addition, the impact of the various interactions on the functional properties of the milk will be discussed with the use of specific examples relevant to common dairy food systems. These examples will exemplify the importance of the protein composition and the interactions between the various proteins in determining the functional properties of dairy protein systems.

236Transforming Food Systems: The Next Frontier of Protein- Enhanced Foods

Baljit Ghotra

EQUII, 1933 Davis Street Suite 232, San Leandro, California, USA
The global environmental crisis and consumer health consciousness have led to increased attention to organic farming. Organic farming not only produces healthier foods, but also leaves fewer chemicals that pollute the waters and soil. Reduction of antibiotic use in agricultural production has been a big challenge to organic farming and the search for using natural bioactive substances to replace conventional antibiotics has intensified. Probiotics, bacteriophage, and essential oils are promising candidates as antibiotic alternatives. Effective protection and delivery of these bioactives to their target sites is a critical step toward the success of such applications. Although encapsulation is shown to be effective in such applications, the selection of encapsulation wall materials that meet organic farming requirements has been a big challenge. This presentation will use two examples to demonstrate the quest for natural hydrocolloids to be applied to encapsulation and delivery of antibiotic alternatives that meet organic farming requirements. One example is for intestinal delivery of essential oils for disease control and improvement of gut health in animals; the other is for delivery of a bacteriophage-based biopesticide for disease control in fruit trees. Various encapsulation techniques, including emulsification, spray drying, and freeze drying are compared and selected according to the respective applications. The results demonstrated that natural hydrocolloids are irreplaceable as encapsulation wall materials for target delivery of bioactive substances as antibiotic alternatives in organic farming.

229Decoding The A2 Dairy Dilemma: Scientific Discovery Meets Industry Application

Davor Daniloski1,2,3*, Noel A. McCarthy3, Todor Vasiljevic2

1School of Chemical Engineering, The University of Queensland, Queensland 4072, Australia
2Advanced Food Systems Research Unit, Institute for Sustainable Industries and Liveable Cities, Victoria University, Melbourne, Victoria 8001, Australia
3Teagasc Food Research Centre, Food Chemistry and Technology Department, Moorepark, Fermoy, P61 C996 Cork, Ireland
Introduction: Bovine milk contains valuable proteins, composed of two major groups, caseins and whey proteins. Among the caseins, β-casein exists predominantly in two genetic variants - A1 and A2. A single difference at position 67 of the β-casein peptide chain with histidine in β-casein A1 and proline in β-casein A2 has ignited a global debate over possible health implications of conventional milk which contains both variants. While health concerns regarding the consumption of conventional milk still remain unsubstantiated, the market is increasingly leaning towards A2/A2 milk. This study explored the potential industry-wide impacts of transitioning to A2/A2 milk, offering crucial insights into the future of dairy.

Methods: To conduct an in-depth analysis of the casein micelle, milk, and dairy products with different genetic variants of β-casein, the samples were studied simultaneously by utilising in-situ spectroscopic techniques, such as Fourier Transform Infrared, Nuclear Magnetic Resonance and Raman spectroscopy, supported by numerous physicochemical, imaging, chromatographic techniques and in vitro digestion patterns.

Results and Discussion: The study revealed that β-casein variants account for at least 50 % of structural differences among the samples. Conventional milk exhibited distinct heat coagulation properties compared to less stable A2/A2 milk. These differences extended to acid- and rennet-induced gels, and their respective products including yogurt and cheese. It was found that the onset of gelation was faster in conventional compared to that in A2/A2 milk. Although the greater gel strength observed in conventional milk may positively affect the techno-functional characteristics of yoghurt or cheese, it may also alter the curd-forming properties during the gastric phase of digestion. Gastric digestion was notably faster for conventional milk and dairy products compared to A2/A2 samples, potentially influencing product digestibility. Several reasons may account for the occurred differences among the samples, including conformational with greater levels of polyproline II helixes, larger casein micelle size, lower total calcium and κ-casein amounts in A2/A2 samples, but also bigger complexes between κ-casein and β-Lactoglobulin compared to conventional milk, which was comprised mainly of α-helical motifs.

This study has identified that milk and dairy products with β-casein A1 and A2 variants are quite different, based on their structure, functionality, and behaviour to environmental factors. The findings suggest substantial implications for transitioning national dairy herds to the A2/A2 phenotype, specifically impacting dairy processors and their products.

Keywords: Conventional milk; A2/A2 milk; gelation; dairy products; gastric digestion

211Lubricity and structure response of human saliva pellicle to the dairy-saliva protein interaction and correlation with sensory perception

N Fan1, H.M. Shewan1, H.E. Smyth2, G.E. Yakubov1,3 and J.R. Stokes1*

1School of Chemical Engineering, The University of Queensland, Brisbane Qld 4072 Australia
2Centre for Nutrition and Food Sciences, Queensland Alliance for Agriculture and Food Innovation, The University of Queensland, Brisbane Qld 4072 Australia
3School of Biosciences, The University of Nottingham, Nottingham NG7 2RD, United Kingdom
Saliva plays a critical role in oral lubrication by coating oral surfaces with a highly hydrated, proteinaceous film with a complex layer structure[1]. The interaction between this salivary film and the ingredients of foods, beverages, and oral care products is hypothesised to influence their sensory perception. Here we focus on the tribological impact arising from interactions between dairy and salivary proteins that are pre-adsorbed to hydrophobic substrates. We explore the effect of dairy proteins on the lubricity of saliva films using our dynamic tribological protocol (DTP)[2], in combination with surface film characterisation and sensory mouthfeel studies. While previous tribological studies with saliva primarily focus on its relevance to astringency perception (tea, wine, and dairy), the solutions studied here are not considered astringent.

In the DTP method, an ex vivo saliva pellicle is formed by adsorbing acid-stimulated human whole saliva onto hydrophobic elastic substrates. Once adsorbed, lubricity is measured before and after exposure to skim milk and whey protein isolate (WPI) mixtures with varying casein to whey protein (C:W) ratios under neutral pH conditions. Trained sensory panellists performed descriptive sensory analysis on the samples. The lubricity of the saliva pellicle decreased upon contact with dairy solutions, with greater decreases corresponding to higher C:W ratios. Friction parameters from DTP are strongly correlated with in-mouth textural attributes such as thickness and smoothness, and after-feel attributes mouth coating and smoothness. The correlation between sensory texture perception and the friction coefficient for samples measured with DTP is significantly higher than the friction coefficient measured with samples alone or viscosity measurements.

To investigate the mechanism driving the decrease in lubricity with an increase in casein content we used surface characterization techniques, such as quartz crystal microbalance with dissipation (QCM-D), atomic force microscopy (AFM), and scanning electron microscopy (SEM)[3]. Our findings indicate that an increase in casein content increases the mass loss from the salivary pellicle. Interaction with whey protein softens the pellicle, whereas exposure to micellar casein causes the pellicle to partially collapse, resulting in a thinner and more rigid layer. These structural changes correlate with lubrication behaviour. Our study highlights the importance of casein-saliva interactions.

This study demonstrates that the saliva-dairy protein interactions play a key role in influencing the structural and lubrication properties of the saliva pellicle. The DTP with saliva-coated substrates offers rich information about oral processes and provides relevant insights into texture and mouthfeel perception during and after the consumption of dairy systems. This knowledge provides insights into how different dairy food and beverage components contribute to mouthfeel, texture perception, and oral hygiene.

Reference:
1. Yakubov, G., et al., Aqueous lubrication by fractionated salivary proteins: Synergistic interaction of mucin polymer brush with low molecular weight macromolecules. Tribology International, 2015. 89: p. 34-45.
2. Fan, N., et al., Dynamic Tribology Protocol (DTP): Response of salivary pellicle to dairy protein interactions validated against sensory perception. Food hydrocolloids, 2021. 113.
3. Fan, N., et al., Structure Response of Preadsorbed Saliva Pellicle to the Interaction between Dairy and Saliva Protein. Langmuir, 2024. 40(22): p. 11516-1152

122Effect of high-intensity ultrasound on physicochemical, structural, and functional properties of bovine milk, goat milk, camel milk, and their mixtures

Mayumi Silva1, Mohamed Musthafa1, Dilusha Munasinghe2, Akalya Shanmugam3,4, Jayani Chandrapala1*

1School of Science, STEM College, RMIT University, Bundoora VIC 3083, Australia
2Department of Food Science and Technology, Faculty of Applied Sciences, University of Sri Jayewardenepura, Sri Lanka
3Food Processing Business Incubation Centre, National Institute of Food Technology, Entrepreneurship and Management – Thanjavur-613005, India.
4Centre of Excellence in Non-Thermal Processing, National Institute of Food Technology, Entrepreneurship and Management - Thanjavur, India
Bovine milk and dairy products have gained more popularity and are commercially exploited worldwide due to the higher customer demand. However, the demand for other non-bovine milk types such as goat milk and camel milk is also growing due to their nutritional values and the high volume of production in certain regions of the world. Thus, this study aimed to research the effect of high-intensity ultrasound on physicochemical, structural, and acid gelation properties of cow, goat, camel milk and their mixtures. Native milks and cow-goat and cow-camel milk mixtures prepared at 75:25, 50:50 and 25:75 (w/w) ratios were treated with 20 kHz ultrasound under different sonication times and analyzed in terms of pH, particle size, zeta potential, gel strength, syneresis and structural changes. Application of ultrasound reduced the particle size in goat and cow milk and their mixtures. Sonication treatment increased the particle size of camel milk whereas in the mixtures, size reduction was observed when the camel milk fraction was ≥50%. Even though the gel strength of native cow and goat milk acid gels can be significantly improved by ultrasound, it was not successful in enhancing the gel strength of acid gels prepared with cow-goat milk mixtures. However, 50:50 ratio of cow-goat mixtures showed improved gel characteristics without the ultrasound application. Camel milk had the weakest gel structure compared to cow and goat milk. Sonication-induced structural/bonding changes of milk proteins significantly contributed to the physicochemical and functional changes occurring in liquid milk and milk gels. The findings of this research provide useful insights to identify the effect of ultrasound conditions and milk protein compositions on the functionality of non-bovine milk systems and their mixtures with bovine milk and to enhance the functionalities of milk systems.

129Introducing Spices to milk and their effects in gelation of milk systems

Mayumi Silva, Jayani Chandrapala, Carolyn Mejares, Alfonso Gosal, Chethiya Waththuhewa, Anil Chaudhary

RMIT University, Bundoora, VIC 3083, Australia
Milk stands as one of the most frequently consumed and nutritionally rich products worldwide, catering to individuals across all age groups. Despite the vast array of primary and secondary dairy products and ingredients already available to consumers, the industry continues to seek product enhancements and innovations. Spices, recognized for their health-promoting attributes such as therapeutic and antioxidant, preservation effects as well as sensory and flavor enhancing properties, primarily find application in culinary contexts. Nevertheless, despite the presence of certain established spice-infused dairy products like chai-milk tea and spiced-tea, their potential benefits for dairy products remain relatively unexplored, limiting the understanding of their maximum potential. Hence, this study aims to investigate the impact of incorporating spices (clove and cinnamon) into different liquid milk systems, while considering the presence or absence of fat and the application of heat treatment on the gelation properties.

Skim milk and whole milk samples were incorporated with cinnamon and clove separately at 3% (w/w) in their whole form. These samples underwent heat treatments at either 80 °C or 90 °C for a period of 10 minutes. After heating, the milk samples were analyzed for physico-chemical and structural charaactoristics. Gelation was induced by the addition of 2.5% (w/w) Glucono-delta-lactone (GDL) and were analyzed for color, texture, water holding capacities, rheological properties, secondary structural and microstructural properties.

The addition of cinnamon and cloves, combined with heat treatments, showed positive effects on the gelation process of both skim and whole milk samples. The initial changes in physicochemical properties, including pH, particle size, zeta potential, and viscosity, along with the modified secondary structural properties of the milk samples, led to these improvements. The spiced milk samples demonstrated reduced gelation time, higher G′ values, increased firmness in gels, and better water-holding capacities compared to the control samples. Differences in gel firmness were linked to gel microstructure, where the structural changes within the spice-containing gels provided denser protein networks. Variation in gelation properties including the time required for the onset of gelation, rheological and textural properties of acid gels produced from skim milk and whole milk with spices are mainly attributed to the differences in fat contents in these systems. Heat-induced changes on the rheological and textural properties of acid gels from skim milk and whole milk were primarily influenced by the protein aggregation process. In summary, these changes in gelation properties depended on the fat composition in milk, the applied heat treatment, and the type of spice used. This knowledge promotes the potential of using spices to modulate the gelation properties of milk systems with enhanced texture and stability.

176How measuring conditions affect the compression loss related to juiciness in plant-based burgers

Raisa E. D. Rudge, Felix Briner, Heather Smyth

QAAFI, University of Queensland, Brisbane, Australia
Juiciness is considered an important yet complex sensory attribute for animal and plant-based meats. The dynamic nature of the textural attribute, influenced by individual ingredients, the overall food matrix, and interactions occurring during oral processing, makes predicting or measuring juiciness instrumentally complex. We hypothesise that sensory juiciness of burgers is related to the release of free moisture during compression. This was tested by performing sensory texture analysis on six animal and six plant-based meat burgers. Sensory results of burgers with various formulations were evaluated using a trained panel and compared to physical measurements of liquid loss upon compression at different compression rates. The sensory results indicated that the PBMA samples were lower in juiciness than the ABM samples regardless of the composition of the food matrix. Juiciness was highest upon the addition of additional water or oil and lowest upon the addition of methylcellulose. However, adding methylcellulose as a premixed foam combined with oil and water rather than as a dry powder resulted in the highest juiciness scores for PBMA. To better understand the dynamics behind juiciness perception, mechanical measurements were performed. Specifically, compression measurements were carried out at various compression rates with the burger crust on or with the crust removed. Then, the percentage of fluid released (compression loss) was determined and the water and non-water fractions were analysed. Similar to the sensory results, it was found that PBMA samples all had significantly lower free liquid release upon compression (compression loss) than ABM samples. Various compression rates were tested, and it was found that the correlations between sensory juiciness and compression loss was strongest at higher compression rates and when measuring with the crust removed. This demonstrates the importance of measuring conditions and sample preparation when mechanical testing is used to analyse textural properties such as juiciness. The results presented here can serve as a tool to further develop PBMA or other food products that seek to address juiciness.

132β-lactoglobulin from precision fermentation for improved heat stability

Kiran Subbarayadu1, Isidora Apostolidi1, Zheng Pan2, Skelte Anema2, Jeremy Hill2, Marcel Wubbolts1, Remco Kornet1

1Vivici BV, Kernhemseweg 2, 6718ZB, Ede, The Netherlands
2Fonterra Cooperative Group, P.O. Box 11 029, Palmerston North, New Zealand
Dairy proteins have long been appreciated for their techno-functional and nutritional properties. With precision fermentation already established as a viable technology for ingredient production, there is growing interest in producing recombinant analogues of dairy proteins. This approach allows for the development of isolates containing specific protein variants, which can be bioequivalent or engineered for enhanced functionality. The functionality of such recombinant dairy protein isolate is then driven by the protein’s molecular characteristics and isolate purity. This study aims to compare the heat stability and aggregation behaviour of recombinant β-lactoglobulin produced via precision fermentation (rBLG) to milk-isolated β-lactoglobulin (BLG) and commercial whey protein isolate (WPI). Using a multilength scale approach, we investigated how molecular and physicochemical characteristics influence heat stability and aggregation behaviour under UHT-mimicking conditions. At the molecular level, although small differences were detected in the primary structure between rBLG and BLG, structural equivalence was confirmed across secondary, tertiary and quaternary structural levels. On a mesoscale, rBLG demonstrated comparable heat stability to BLG and WPI under acidic pH conditions, while exhibiting superior heat stability at neutral pH. This enhanced stability was related to the molecular characteristics of rBLG and further supported by electrophoretic mobility measurements. The aggregate characteristics and viscosity contribution after heating were also evaluated. It was found that the heated rBLG had a lower viscosity contribution and specific volume compared to BLG and WPI. Finally, the heat stability of rBLG was evaluated in mineral-fortified model food systems. Our findings suggest that even minor variations in the primary structure can significantly impact ingredient functionality in food applications. These insights could encourage further research into precision fermentation as a tool for developing protein variants tailored to specific functionalities.

151Interfacial Activity of Fucoidan for Enhancing its Bioactivity

Cundong Xie1, Michael G. Leeming2, Zu Jia Lee1, Shenggen Yao2, Muthupandian Ashokkumar3, and Hafiz A. R. Suleria1

1School of Agriculture, Food and Ecosystem Sciences, The University of Melbourne, Parkville, VIC, Australia
2Bio21 Molecular Science and Biotechnology Institute, The University of Melbourne, Parkville, VIC, Australia
3 School of Chemistry, The University of Melbourne, Parkville, VIC, Australia
As a significant sulfated polysaccharide present in brown seaweeds, the prominent bioactivities of fucoidan have attracted increasing attention from food scientists. Recent studies have highlighted the potential structural damages triggered by gastrointestinal digestion, which is thought to reduce the bioactive performance of fucoidan. In this study, we aimed to validate the feasibility of sustaining the bioactivities of fucoidan in a digestive environment by incorporating fucoidan at the interface of an oil/water emulsion. The effects of the digestive progression on fucoidan structures and bioactivities were traced by the dynamic changes in reducing sugar content (CR) and radical scavenging activities of digesta collected from different simulated digestion timeframes. We observed that the DPPH radical scavenging rate increased from 23% for fucoidan in a free form (0.25%; w/w) to 94% for fucoidan incorporated in an emulsion. The fucoidan-stabilized emulsion retained superior antioxidant potential throughout the simulated gastrointestinal tract, which is possibly due to improved structural integrity since lower CR was identified in its small intestinal digesta. These data provide comprehensive information on the enhancement in physiochemical properties and bioactivities of fucoidan after transferring from a continuous phase to an interface in a simulated gastrointestinal environment. The survival of fucoidan-stabilized emulsion from a simulated digestive environment validated a new supplementing approach for fucoidan.

144Partial substitution of dairy protein with Spirulina protein in milk mimetic formulations: studies on physicochemical and techno-functional properties

Jayani Samarathunga1*, Max Gabard2, Katrina Strazdins2, Jeroen Rens2, Benu Adhikari1*

1School of Science, RMIT University, Melbourne, VIC 3083, Australia
2Bega Group, Melbourne, VIC 3008, Australia
Spirulina platensis, a blue-green algae has become a popular source of protein now. Spirulina protein is helping to meet growing consumer demand for protein. Among various proteins, dairy proteins are the most frequently consumed and are available in dairy products as well as in mixed food formulations. However, in recent years, consumers are increasingly opting for dairy mimetic products due to various reasons. In this study, protein from Spirulina biomass was extracted using pH-shifting method (pH 12 and pH 3) and was used to formulate dairy mimetic products. Five model milk mimetic formulations (MMFs) were prepared with protein (3.3%), fat (3.5%), lactose (5.0%) and mineral concentrations similar to bovine milk by replacing the bovine protein fraction by Spirulina protein concentrate (SPC) at 0% (100% MPC, control), 25% (25% SPC), 50% (50% SPC), 75% (75% SPC) and 100% (100% SPC) (w/w). SPC (81.5±0.2% protein ), anhydrous dairy fat (99.9% fat) and simulated milk ultrafiltrate (SMUF; milk minerals), milk protein concentrate (MPC; 85% protein) were used in the above formulations and were homogenized at 62 MPa with 3 passes using microfluidizer. Confocal laser scanning and light microscopic images of all MMFs elicited a homogenized oil in water emulsion. Emulsion stability was observed by particle size distributions and creaming index of MMFs throughout storage period (4 °C) of 15 days. The particle size values (D [4, 3], volume weighted mean diameter) of each MMFs increased during the storage time and values were significantly different (P value < 0.05). Aggregation of MMFs was detected only in 100% MPC on the 15th day. The creaming index of all the MMFs was only marginally reduced during the storage (100% to 97%). Colour parameters of the five MMFs were significantly different from each other (P value < 0.05). Replacement of MPC with SPC reduced the lightness of model milk and increased the brownness. pH value of all MMFs only marginally decreased during storage (pH 6.8 to pH 6.6). The zeta potential of MMFs with higher proportion of SPC had higher negative value. The increase of SPC proportion in the MMFs increased the shear viscosity. The formulation with100% SPC had significantly high viscosity than the one with 100% MPC. Some degree of denaturation and aggregation of protein was observed in all formulations due to high pressure applied in the homogenization process. The thermal stability of SPC (65-75°C) was lower compared to MPC (117-125°C). Thus, the MMFs with higher proportion of SPC would be sensitive to thermal treatment yet would be favourable to form gelled products (e.g., mimetic yoghurt). Therefore, this study will contribute to innovation, diversity, and sustainability of the food industry.

Keywords: Spirulina platensis, dairy mimetic, protein, model milk, emulsion

112Effectiveness of alternative polymer binders for use in toothpastes

Glen Redpath1, Lisa Manus2, Andrei Potanin2, Tim W Overton1, Eddie Pelan1

1School of Chemical Engineering, University of Birmingham, Edgbaston, B15 2TT
2Colgate-Palmolive Company, 909 River Road, Piscataway, NJ, 08854, USA
A typical toothpaste formulation includes solids (abrasives, rheology modifiers), aqueous polyol(s), hydrocolloid binder(s), active ingredients, flavourings and preservatives. Existing products have specific rheological properties to meet consumer requirements; high yield stresses for stand-up, shear-thinning and therefore can be extruded from a tube, and low levels of ‘stringiness’ so that paste application is not wasteful or messy. These consumer metrics have been correlated with rheological/tribological properties in the past (1,2).

Gellan gum does not appear widely in commercial toothpaste formulations but is w/w% highly effective as a viscosity modifier. The motivation of this work is to study and quantify the potential use of high acyl gellan gum as an alternative or (synergetic) additive polymer binder in toothpaste formulations. Locust bean gum, commonly known to have a synergistic interaction with xanthan gum (3), has also been shown to improve rheological properties.

Rotational rheology and mechanical texture analysis were employed to characterise the behaviour of the model pastes. A bespoke geometry and testing/processing protocols have been developed to characterise ‘stringiness’ based on previous methods (1). Tribological properties of pastes have also been compared, utilising a prototype 3-ball tribo-rheometry attachment (Netzsch).

Binders used traditionally in toothpastes, such as xanthan gum and sodium CMC, exhibited stand-up and stringiness consistent with previous work (1). Formulations containing gellan gum had excellent stand-up properties for very low w/w%. Formulations containing cellulose derivatives were significantly more ‘‘stringy’ than those without.

Based on the findings of this work, there could be opportunities to consider the use of more non-traditional binders like gellan and locust bean gum in toothpaste formulations to achieve comparable, consumer-relevant properties of products.

    References
  1. Ahuja A, Potanin A. Rheological and sensory properties of toothpastes. Rheol Acta. 2018;57(6–7):459–71.
  2. Cai H, Li Y, Chen J. Biotribology Rheology and Tribology Study of the Sensory Perception of Oral Care Products. Biotribology [Internet]. 2017;10(March):17–25. Available from: http://dx.doi.org/10.1016/j.biotri.2017.03.001
  3. Schreiber C, Ghebremedhin M, Zielbauer B, Dietz N, Vilgis TA. Interaction of xanthan gums with galacto- And glucomannans. part I: Molecular interactions and synergism in cold gelled systems. JPhys Mater. 2020;3(3).

127Investigation of physicochemical, structural and nutritional properties of malted milk powders enriched with germinated cereals and pulses

Chamodi Gunathunga1,2, Jayani Chandrapala1*, R.A.U.J. Marapana2, Charles Stephen Brennan1, Tuyen Truong3, Suraji Senanayake2, Madhura Jayasinghe2

1School of Science, RMIT University, Melbourne, Australia
2Department of Food Science and Technology, Faculty of Applied Sciences, University of Sri Jayewardenepura, Gangodawila, Nugegoda, Sri Lanka
3School of Science, Engineering & Technology, RMIT University, Vietnam
* Corresponding Author
Integration of germinated cereal and pulses into dairy- based functional foods is a promising strategy to enhance macronutrients and bioactive compounds through structural and interaction modifications within the food matrix. This study mainly focuses of investigating a convenient instant malted milk powder using germinated rice, maize, and green gram and to characterize its physiochemical properties. This study primarily aims to examine a convenient instant malted milk powder made from germinated rice, maize, and green gram, focusing on characterizing its physiochemical, structural, and nutritional properties.

Malted milk powder was formulated by incorporating a germinated flour mix into milk at three distinct ratios (40:60, 50:50, and 60:40). The malted milk powders were evaluated for total polyphenol content (TPC), total flavonoid content (TFC), antioxidant activity, protein and fat content as well, physical properties including particle size, solubility, and color.

The study found that malted milk powder which contained 60 % germinated malt mix had the highest TPC, TFC and antioxidant activity. Concurrently, the highest protein content was given by the 60:40 malted milk powder, compared to control samples while fat and ash content remaining constant across all samples. Improving the contents of bioactive compounds in germinated cereal and pulses mainly directs to the increment of bioactivities in malted milk powder. The activation of amylolytic and protease enzymes during germination breaks down phenolic-starch and phenolic-protein complexes, releasing bound polyphenols into the cell matrix is accountable for the increment of bioactive compounds. Moreover, the structural changes in starch and proteins, including the separation of starch granules from proteins and the formation of cracks in starch surfaces leads to increase the polyphenols and flavonoids in malted milk powder.

The solubility of the malted milk powders in water improved with the addition of germinated malt due to the loosening of protein and starch complexes, leading to altered macromolecule shapes and exposing hydrophilic moieties that bind with water. Concurrently, process of germination also leads to an increase in particle size, due to the electrostatic attraction between acidic proteins in milk and amino acids from the germinated cereals and pulses. However, the particle size was not affected to the solubility of malted milk powder because of the microlevel interaction happen between macromolecules in germinated cereal and pulses and milk. Furthermore, the malted milk powders with higher germinated malt content exhibited a color shift from light brown to dark brown.

The study shows that germination is important for boosting the nutrients and bioactivities of malted milk powder. This enhancement occurs through structural alterations in starch and proteins, which subsequently influence their binding affinities. The results open new pathways for further research and development in the functional foods industry, with potential applications in hydrocolloidal foods with bioactivities using such simple bioprocesses, that serve to health-conscious consumers.

180New Zealand’s hide and skin co-products: an old dog ready for new tricks?

Zoheb Akhter, Siew Ling Ong*

Leather and Shoe Research Association of New Zealand (LASRA), 69 Dairy Farm Road, Massey University, Palmerston North 4410, New Zealand.
New Zealand has been a traditionally primary-based exporting economy, contributing 10.5% to the nation’s GDP as of 2022. In particular, meat exports are projected to rise by 3% annually for the next five years. This creates a surplus of the availability of red meat co-products such as hide and skin since the demand for them is relatively stagnant. On the other hand, the pet food export in NZ has observed strong performance in recent years by maintaining its reputation through research innovation and its unique, infectious animal disease-free nation. This provides an opportunity to transform these by-products into sustainable and nutritious pet food protein components. Here, we assessed the opportunity of turning NZ skin and hide into mid-to-high-value co-products to support the growing consumer’s appetite for premium pet food products. Four co-products were characterised and investigated, including palatability and digestibility assessment through a wet diet. The outcome of these studies will shed light on the latter stage of product development, which will inform the appeal of these ingredients and determine the nutritional value provided to the canine’s diet.

159A tale of two biopolymers: the role of hemicellulose and lignin in the interfacial activity of birch glucuronoxylans

Felix Abik1, Thao Minh Ho1,2, Kirsi S. Mikkonen1,2

1Department of Food and Nutrition, University of Helsinki, P.O. Box 66, 00014 University of Helsinki, Finland.
2Helsinki Institute of Sustainability Science (HELSUS), University of Helsinki, P.O. Box 65, 00014 University of Helsinki, Finland.
The rapid growth of human population, alongside the continuously worsening climate crisis, increases the demand for alternative sources of materials that are both sustainable and environmentally compatible, to either replace or supplement those currently available. For this purpose, lignocellulosic materials have received a lot of attention, as they can easily be extracted from by-products of the agriculture and forestry industries, and the obtained products are generally considered to be environmentally friendly. One example is the utilization of residual sawdust from the pulp and paper industry. The collected sawdust can be treated with pressurized hot water to yield hemicellulose extracts that have the potential as emulsifiers for various applications. These extracts were proven to have remarkable emulsifying properties, being able to create submicron emulsion droplets with comparable physical stability to other established polysaccharide-based emulsifiers despite having a low, water-like viscosity. They also contain a significant amount of residual lignin, which endows some protection to the oil phase against oxidation. However, the extracts exist as a complex mixture of polysaccharides, insoluble lignin particles, and covalently-linked lignin-carbohydrate complexes (LCC). All of those components have been shown to contribute towards the emulsion stabilization mechanism, but their specific roles have not been elucidated. In this study, we focused on glucuronoxylans (GX) extracted from birch wood, employing various characterization methods to connect the puzzle pieces of the interplay between polysaccharide and lignin at the oil-water interface. Firstly, through measurements of dynamic interfacial tension and quartz crystal microgravimetry, we demonstrated that the lignin fraction is responsible for enabling the adsorption of GX, forming a polysaccharide-rich interfacial layer. Secondly, through in vitro digestion experiments, we simultaneously showed the viability of GX-stabilized emulsions as a carrier of vitamin D3, the polysaccharide-dominant character of the interfacial layer, and the localization of the lignin fraction towards the oil phase. Finally, an exploration of the effect of pH and salt in the aqueous phase of the emulsions towards their stability confirmed the dual role of the lignin fraction. The lignin fraction enabled the formation of a protective layer at the interface, but on the other hand encouraged the destabilization of the emulsions when present in excess. The results of our current study further clarified the roles of the polysaccharide and lignin fractions in the emulsion stabilization mechanism, where the polysaccharide fraction builds the bulk of the interfacial layer, while the residual lignin drives the adsorption of the hemicelluloses to the interface. This more comprehensive knowledge of the stabilization mechanism provides additional scientific basis towards a more rational extraction and fractionation strategy of hemicelluloses from lignocellulosic feedstocks, leading to emulsifiers that are tailorable to the intended emulsion-based products.

139Physical, Chemical and Functional Properties of Yoghurts Enriched with Cooked Arrowroot and Potato Flour.

Sankha Karunarathna1,2, Jayani Chandrapala1*, Seneviratne Navaratne2, Indira Wickramasinghe2, Charles Brennan1, Tuyen Truong1

1School of Science, RMIT University, Bundoora, Victoria, 3083, Australia.
2 Department of Food Science and Technology, University of Sri Jayewardenepura, Nugegoda 10250, Sri Lanka.
*Corresponding Author: jayani.chandrapala@rmit.edu.au
Potato flour and arrowroot flour are increasingly recognised for their high content of resistant starch, which has notable implications for human health. This contributes to potential health benefits, including improvements in gastrointestinal health and possible reductions in the risks of developing chronic diseases such as Type 2 diabetes and colorectal cancer. The incorporation of these flours into health-oriented food products has attracted considerable attention due to their dual role in enhancing both the nutritional profile and sensory qualities of foods. This makes them valuable as functional ingredients in the food industry, fulfilling the demand for products that are healthful yet palatable for consumers.
Initially, arrowroot and potatoes were cooked using various cooking methods such as boiling and pressure cooking as a function of time (10-45 min). Then, the treated samples were freeze-dried and incorporated into yoghurt samples with various ratios. Raw potatoes and arrowroots were taken to make the control samples. A comprehensive set of analytical techniques was employed to evaluate the physicochemical and structural properties of the freeze-dried powders as well as the enriched yoghurt samples. The powder characterisation included the determination of resistant starch content (RS%), scanning electron microscopy (SEM), attenuated total reflectance- Fourier transform infrared spectroscopy (ATR-FTIR), X-ray diffraction analysis (XRD), particle size distribution (PSD) and solubility. Yoghurt's characterisation included texture profile analysis, colour, viscosity, rheology, and syneresis.
The research findings demonstrated that the physical structure of starch granules underwent significant changes, resulting in a reduction in crystallinity and an enhancement in digestibility. Moreover, it was observed that the content of resistant starch in flour decreased notably following exposure to a variety of cooking techniques. Additionally, the solubility of treated and freeze-dried potato and arrowroot powders markedly increased after the aforementioned cooking methods. These results suggest a promising potential for modifying starch granules to optimise the functional characteristics of flours. The characteristics of fortified yoghurts were altered by several factors, including the variety of flour introduced, the proportion of flour added, and the specific method employed in the flour preparation. The changes witnessed in different types of cooked flour are a result of the gelatinisation process that takes place during cooking. The study findings demonstrate that the cooking process brings about alterations in the physical, chemical, and structural characteristics of potatoes and arrowroots, which can be used to make functional foods with extra health benefits.

143Valorising side streams: Properties of legume dry and wet fractionation by-products

Ruoxin Liu1, Bernadine M. Flanagan1, Vishal Ratanpaul2, Michael J. Gidley1

1Centre for Nutrition and Food Sciences, Queensland Alliance for Agriculture and Food Innovation, The University of Queensland, St Lucia, QLD, 4072, Australia
2CSIRO, Agriculture and Food, 671 Sneydes Road, Werribee, VIC 3030, Australia
Introduction:
The growing demand for plant-based protein foods increases the need to produce plant protein ingredients. Legumes are one of the good plant-based protein sources, which are rich in essential amino acids and are of high protein quality. The legume protein fractionation process focuses on producing protein concentrates or isolates while large amounts of protein-deficient fractions (mainly starch and fibre) are considered waste or are used as animal feed. This research focuses on recovering the protein-deficient fractions from side streams during dry fractionation and wet fractionation and understanding the properties of those fractions as potential food ingredients.

Method:
Dry fractionation (air classification) and wet fractionation (alkaline extraction and isoelectric point precipitation) were used to produce protein-rich and protein-deficient fractions of 5 legumes (Desi chickpea, Kabuli chickpea, lupin, mung bean and faba bean). The composition, yield, and recovery of dehulled legume flour and protein-deficient fractions were determined. The functional properties, including water holding capacity, oil holding capacity, swelling power and water solubility index of protein-deficient fractions were determined and compared between different fractionation methods.

Results:
Protein-deficient fractions represented more than half of the starting legume with composition and functional properties dependent on both legume source and fractionation method. Wet fractionation produced high-purity protein isolates and protein-deficient fractions (fibre-rich and starch-rich fractions), and dry fractionation produced low-purity protein concentrates and protein-deficient fractions (coarse fractions). Fibre-rich fractions showed good water and oil holding capacities and starch-rich fractions showed good swelling power. Dry fractionation protein-deficient fractions showed similar composition and properties compared to legume flour and can be considered as a potential substitution in food products.

Discussion:
Two fractionation processes produced potentially valuable protein-deficient fractions for each of the five legumes. The results indicate that different fractions contribute to different properties, which may have different and sought-after functionalities for incorporation into food products. This project contributes to achieving a state-of-the-art production chain that considers the values of both protein-rich and protein-deficient fractions when selecting legume sources and fractionation process conditions.

164Achieving in-vitro tablet breakup by spray drying different additives with caffeine or physical mixing and the connection between breakup, mass transfer and texture in digestion

Jingying Cheng, Timothy A.G. Langrish

Drying and Process Technology Research Group, School of Chemical and Biomolecular Engineering, The University of Sydney, Darlington, NSW, 2008, Australia
Studying the breakup process in food digestion can help predict and control nutrients released in the human diet. This work has developed tablets with well-characterised mechanical properties, and this process has been achieved by changing different spray-drying aids (pectin, microcrystalline cellulose), and by the physical mixing of microcrystalline cellulose with caffeine. The mass-transfer behaviour during breakup has been studied at the same time in an in-vitro beaker system. The tablets containing microcrystalline cellulose (MCC) dissolved uniformly at the beginning and then experienced tablet attrition, followed by tablet break-up. The tablets containing pectin showed only a dissolution process, while the physical mixing tablets showed a disintegration process. Changes in the mass-transfer behaviour were also apparent when the breakup process occurred, where the slope of the concentration-time curve (mass transfer) changed by an order of magnitude when the break-up occurred at 1.8 minutes. The Young’s modulus changes with the different digestion times, and this change is also connected the disintegration phenomena. This study helps to understand the breakup process in digestion and its connection with changes in the mass-transfer behaviour and the mechanical properties, which may assist in controlling the nutrients released when producing new foods or tablets.

169Investigation of the physical properties and microstructure in hybrid processed cheese formulated with plant protein ingredients and rennet casein

Di Lu1, Debashree Roy1, Alejandra Acevedo-Fani1, Harjinder Singh1, Cushla McGoverin2, and Aiqian Ye1*

1Riddet Institute, Massey University, Private Bag 11 222, Palmerston North, 4442, New Zealand
2Department of Physics, University of Auckland, New Zealand
This study investigates the physical properties of hybrid processed cheese analogues (HPCAs) derived from plant proteins and rennet casein, aiming to understand the spatial and microstructural distribution of these components and their implications for cheese functionalities. The study involves mixing hemp protein or mung bean protein with rennet casein at various ratios to explore the interaction mechanisms among plant proteins, casein, and lipids in hybrid cheese matrices. Comprehensive analysis included rheological properties, solubility, texture profile, meltability, and stretchability of cheese samples. Protein composition and secondary protein structure were studied using SDS-PAGE and FTIR spectroscopy. Confocal microscopy and TEM were employed to visualize the spatial distribution and microstructure of the main components in the cheese matrix. The results revealed significant variations in the physical properties and microstructure of HPCAs based on plant protein types and plant protein to rennet ratio. The addition of 30% or more plant protein affects the physical and textural properties and microstructure of cheese analogues, with poor fat emulsification. Mung bean protein-based HPCAs exhibit better stretchability, rheological, and textural properties, but not meltability, compared to the hemp protein system at the same mixing ratios. This difference is possibly related to the size of the plant protein aggregation. These findings deepen our understanding of plant protein-based and hybrid cheeses, paving the way for optimized plant-based dairy alternatives.

155Camel milk at the air-water interface

Rodrigo Narea1, Vassilis Kontogiorgos2, Nidhi Bansal3

1School of Agricultural and Food Sustainability, The University of Queensland, Brisbane, QLD, Australia
2Food, Nutrition and Health, Faculty of Land and Food Systems, The University British Columbia, Vancouver, BC, Canada
3School of Agricultural and Food Sustainability, The University of Queensland, Brisbane, QLD, Australia
Foam for coffee beverages is characterised by its uniform micron-sized bubbles, which provide mouthfeel and elasticity features to foam. In smaller bubbles, films undergo a larger strain from their gas expansion, exceeding the LVE regime. Consequently, the mechanical properties of film microstructure play a critical role in avoiding film deformation. This work investigated the interfacial attributes of camel milk (CM) vs bovine milk (BM) at the air-water interface and their influence on bubble behaviour and foam rheology. Interfacial properties were identified using axisymmetric drop-shape analysis. Lissajous curves and intracycle moduli were employed to define the viscoelastic properties of films. Foam characterisation was assessed in samples prepared by steam injection. Protein identification was conducted by gel electrophoresis. Ward Tordai and Graham Phillips models revealed a faster diffusion (Kdiff 0.399 mN/m s-0.5) and adsorption (Kads 0.0026 s-1) for CM. Greater elasticity (~40 mN/m) and strain hardening behaviour at expansion supported a lower bubble growth rate (~4.24 µm²/s) and higher foam viscosity (~3700 Pa.s) in CM. The composition of globular proteins differed between CM and BM, but milk proteins did not show selective adsorption at the interface. The mechanical properties of films influenced bubble stability and foam rheology. The non-linear response at 30% deformation demonstrated the rigid microstructure of CM films. Composition and adsorption hierarchy of globular proteins supported film properties. Overall, CM had better interfacial properties than BM for coffee beverage foams.

177Effect of composition, water content and citric acid on the foam formation and foaming properties of yellow pea and black Beluga lentil purees

Guillaume Morin1,2,3, Audrey Gilbert1,2, Véronique Perreault2,3,4, Sylvie L. Turgeon1,2,3

1Department of Food Science, Université Laval, Québec, Canada
2Institut sur la nutrition et les aliments fonctionnels (INAF), Université Laval, Québec, Canada
3GastronomiQc Lab, joint research unit, ITHQ-Université Laval, Montréal-Québec, Canada
4Institut de tourisme et d’hôtellerie du Québec (ITHQ), Montréal, Canada
Consumers are constantly looking for innovative products made from a short list of natural and locally produced ingredients. Canada is one of the largest producers of pulses worldwide, but its production is mainly exported. Pulses could be processed by cooking and grinding them in their cooking water for use as an ingredient without having generated any co-products. However, little is yet known about the functional properties of such an ingredient.

The aim of this study is to determine the effect of the composition, water content and the addition of citric acid on the foaming properties of pulses purees. Whole yellow pea and black Beluga lentil purees were produced with 95.0, 92.5, 90.0 and 87.5 % of water. Apparent viscosity was determined by increasing logarithmically the shear rate from 0,01 to 300 s-1. Firmness and consistency were determined by a back-extrusion method. The purees were whipped with or without 0.2 % of citric acid for 32 minutes using a stand mixer. Overrun (OR%) was measured at different times during the whipping process. The foam was also characterized by oscillatory shear measurements at the end of the whipping process.

All the purees showed a shear-thinning behaviour. As the water content of the puree decreases, apparent viscosity, firmness and consistency of the puree increases. Firmness and consistency of the pea purees are generally higher than those of lentil purees. This could be attributed to the higher content of starch and fibres in pea purees. According to the type of pulses, the water content of the purees, and the addition or not of citric acid, each puree has its own foam formation kinetic. Most foaming curves increased gradually to reach a plateau while others increased linearly throughout the foaming process. The curves were modelled to determine the rate of increase of the overrun at the beginning of the whipping process. Overrun mostly increases faster as the water content decreases. Lentil purees have a higher protein content and generally produced foams with higher overrun values. Overrun is higher when the foam is made from purees containing 92.5 % of water and it decreases when the water content decreases, probably due to the greater viscosity of the 90.0 and 87.5 % water purees. However, particles at the latter two concentrations would help to increase the stability of the foam after 24 h storage at 4 °C. The addition of citric acid contributes to increasing the overrun and the storage modulus of all foam.

These results show that pulses purees can be used in foamed products. Water content has proven to be a lever to modulate pulses purees properties; an optimal water content would allow having enough surface-active molecules such as protein to form the foam and enough particles to stabilize the film around the air bubbles. Pulses purees become ingredients with great potential for use in foamed food such as chocolate mousse or fruit mousse, allowing creating new textures.

148Role of hydrocolloids in the production of long-chain polyunsaturated fatty acids (LCPUFAs) oil encapsulated powders with potato protein

Mario Alayon Marichal and Yun Xu

Nu-Mega Ingredients Pty Ltd.
Regular consumption of LCPUFAs has been well associated with numerous health benefits such as improved cardiovascular function, diabetes, arthritis, and various inflammatory-related conditions. The application of LCPUFAs in food fortification is challenging because of their poor water solubility and rapid oxidation. One common technology used to address the limitations of LCPUFAs in food, is through microencapsulation of oil in powder. Prior to the production of LCPUFAs in powder, a stable emulsion is required. During the formulation of the emulsion, more than one hydrocolloid may be used and the interaction between them produces either a stable or unstable system. Growing demand for plant-based food and ingredients has prompted many food companies to replace animal with plant-based ingredients in their product formulations. Potato protein isolate (PPI) was used as a replacement of an animal-based protein for the formulation of the LCPUFAs powder. Potato proteins are isolated from the side-stream of starch production and exhibit good functional properties. Their nutritional value is comparable to egg protein with a high content of lysine. The effect of heat-treatment, ions, bulk materials, protein concentration and co-encapsulation with various polysaccharides were examined in the formulation of the LCPUFAs powder. Heat-treatment of PPI was observed to be critical in maintaining a free-flowing emulsion after homogenization. Sodium ions caused precipitation of the PPI due to a salting-out effect. PPI concentration was optimized and selection of the dextrose equivalent (DE) of sugars (DE30) improved the surface free fat and oxidative property of the spray-dried 60% w/w Algal oil powder. Co-solubility of PPI was attained with Agar and Guar gum, where other anionic polysaccharides (Pectin, Gellan and Gum Arabic) would either gel or aggregate with the PPI at specific ratios. Microencapsulation with use of PPI and Agar was shown to further reduce the surface free fat content of spray-dried 60% w/w Algal oil powder. This is the first reported study of a wholly plant-based nutritive ingredient that highlights the functional capacity of PPI and considerations for its use.

106The effect of polyphenol-protein interactions on the pasting viscosity of purple waxy rice

Annegret Jannasch, Ya-Jane Wang, Sun-Ok Lee

Department of Food Science, University of Arkansas, Fayetteville, AR 72703, USA.
Starch improves many food properties, but the use of unmodified starch is limited in commercial applications. Chemical modifications such as crosslinking are commonly used to improve starch stability under high shear, temperature and acidity, but chemically modified starches are not considered as “clean-label” ingredients. Recent results show that polyphenols can interact with cereal proteins to modify rheological properties, implying their role as crosslinkers. Purple rice is rich in bran polyphenols, namely anthocyanins, and hydrothermal processing enhances interactions between polyphenols and protein. The effect of covalent and non-covalent interactions on the pasting viscosity of whole grain and milled rice of non-pigmented (Neches) and purple (HB-1) waxy rice cultivars was studied by using chemical agents including dithiothreitol (DTT), urea, sodium chloride (NaCl), and acidic (pH 2) and alkaline (pH 12) environments. Molecular weight profiles of proteins were obtained via native-PAGE and SDS-PAGE with the addition of DTT, representing the folded/native state and unfolded/denatured state, respectively. The secondary and tertiary structures of proteins as affected by polyphenols were investigated by circular dichroism (CD) and fluorescence emission spectroscopy, respectively. The results show that urea did not affect pasting viscosity of both cultivars. Addition of NaCl increased the pasting viscosity of whole grain Neches and HB-1 and milled Neches, but not that of milled HB-1. DTT reduced the pasting viscosity of Neches, whereas that of HB-1 decreased only moderately. Whole grain Neches and HB-1 and milled Neches exhibited greater pasting viscosity at pH 2, whereas milled HB-1 was unaffected. Pasting viscosity of Neches was only slightly affected at pH 12, whereas that of whole grain HB-1 increased and milled HB-1 decreased. Protein fractions of both cultivars shared similar molecular weight and secondary structures, but polyphenols affected the tertiary structure. The results suggest that the covalent polyphenol-protein bonds played the predominant role, whereas hydrogen bonds and hydrophobic interactions may not play an important role in the viscosity development of purple waxy rice. Anthocyanins in purple rice may bind with glutelin more effectively than phenolic acids in non-pigmented rice, leading to enhanced stability of the protein network at pH 2 and in the presence of DTT, but the network was disrupted at pH 12. Covalent complexation of rice protein with anthocyanins may provide starch with enhanced pasting viscosity and stability in neutral and acidic environments, similar to that of chemically crosslinked starch. This study demonstrates the potential for utilizing polyphenol-protein complexes as a clean-label ingredient to alter pasting properties of starch-based food products.

257Heat-set gelation of milk-isolated and recombinant β-LG

Zheng Pan3, Remco Kornet1, Sheelagh Hewitt2, Jeremy Hill2,, Marcel Wulbbots1, Warren McNabb3, Aiqian Ye3, Alejandra Acevedo-Fani3, Skelte Anema2,3,4,*

1Vivici BV, Alexander Fleminglaan 1, 2613AX Delft, The Netherlands
2Fonterra Research and Development Centre, Private Bag 11029, Dairy Farm Road, Palmerston North 4442, New Zealand
3Riddet Institute, Massey University, Private Bag 11222, Palmerston North 4442, New Zealand.
4School of Food and Advanced Technology, Massey University, Private Bag 11 222, Palmerston North, New Zealand.
Milk-isolated and recombinant β-lactoglobulin may slightly differ in their amino acid sequence, which has been shown to affect its functionality in applications. Research on the heat-induced gelling characteristics of recombinant β-lactoglobulin (β-LG) in comparison with the natural variants is scarce. This study aims to investigate the heat-set gelling behaviour of bovine β-LG A (β-LG A) isolated from milk and a recombinant β-LG A (rβ-LG A) produced via precision fermentation. Differential scanning calorimetry (DSC) was employed to determine the denaturation temperatures of both proteins. The gelling behaviour and macroscopic and microstructural gel properties were evaluated through visual inspection, confocal microscopy, and small and large amplitude oscillatory shear rheology. DSC results indicated that both β-LG A and rβ-LG A had similar denaturation temperatures at approximately 75°C. However, the heat-set gels formed by these proteins exhibited distinct structural differences: rβ-LG A formed a translucent gel with a fine-stranded structure, whereas β-LG A formed an opaque gel with a coarse particulate structure. The gelling profile revealed a delayed gelation onset and lower gel stiffness in rβ-LG A compared to β-LG A. Rheological analysis showed that rβ-LG A gels had a more elastic and ductile texture compared to β-LG A gels, indicated by smaller tan δ values and delayed increases in energy dissipation ratio at higher strain amplitude. These findings highlight the significant impact of protein variants on the heat-set gelation functionality of β-LG A. The more elastic and ductile nature of rβ-LG A gels indicates their potential for applications where these textural properties are required. Previous studies have shown that bovine β-LG variants exhibit differences in their heat-set gelling behaviour. Therefore, by selectively extracting bovine β-LG variants from milk and/or utilizing precision fermentation to engineer additional differences, it is possible to tailor the gelation characteristics of β-LG A to meet specific functional requirements.

258Encapsulation of Algal Omega-3 Fatty Acids Using Functional Hydrocolloids for Targeted Delivery in Plant-Based food alternatives

Shweta Sahni1, Ratnakinerra Kode1 and Munish Puri1,2

1Bioprocessing Lab, College of Medicine and Public Health, Flinders University, Adelaide, Australia.
2Food Bioprocessing Laboratory, Riddet Institute, Massey University, New Zealand.
Omega-3 fatty acids, particularly eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA), derived from algal biomass, are essential nutrients recognized for their health benefits, including cardiovascular support, anti-inflammatory properties, and cognitive health. However, their incorporation into functional foods, such as plant-based dairy and meat alternatives, poses significant challenges due to their instability, susceptibility to oxidation, and unpleasant taste profiles. This study explores the heterotrophic microalgal biomass production and encapsulation of algal omega-3 fatty acids using functional hydrocolloids to understand stability, control release, and mask undesirable sensory attributes, facilitating their application in plant-based food products.

We utilized a range of hydrocolloids, including alginate, and carrageenan, to encapsulate omega-3 fatty acids through coacervation and gelation techniques. The encapsulated particles were characterized for their physicochemical properties, including particle size, encapsulation efficiency, and oxidative stability. Our findings that cover hydrocolloid-encapsulated omega-3 fatty acids for their role in protection against oxidation and improved sensory acceptability would be discussed. The proposed approach holds promise for enhancing the nutritional profile of plant-based dairy and meat alternatives, thereby contributing to the development of healthier, sustainable food systems.

188Standardised analytical methods for the analysis of plant-based milk products' emulsion components

Tina Nduaya Kayeye1, Yuling Wang1, Alison Rodger1,2

1Australian Research Council training center Facilitated Advancement of Australia's Bioactives (FAAB), Natural Sciences, Macquarie University, Australia
2Research School of Chemistry, ANU College of Science, The Australian National University, Australia
Plant milks are attractive to many people as they provide an alternative to dairy milk for conditions such as lactose-intolerance, heart disease or simply a life-style change. They are produced by combining water extracts of plant material such as oat flour with vegetable oils, enzymes, buffers and vitamins in the process of shearing, homogenization and ultra-high temperature treatment (UHT) to produce a stable and functional product. In general, it is assumed that if the same manufacturing process is followed the product will be the same. Due to the seasonal and geographical variability of plant material used in manufacturing, there will be inevitable differences in the product components which affects product quality. However, there is a lack of analytical methods to measure the product components for quality control purposes in a standardised manner to show any component differences. This work is about developing robust analytical methods to characterise the components of plant-based milks. Methods include size exclusion, high-performance of anion exchange and high -pressure liquid chromatography with refractive index detection, and total estimation (anthrone test) for sugars; light scattering techniques (dynamic and zeta potential) for particle size and surface charge, and gas chromatography for fatty acid analysis. Protein content was measured using bicinchoninic acid protein assay. These standardised approaches will assist in quality control of plant-based milk products to ensure a product consistency for consumer satisfaction.

116Concentration-Dependent Behaviour of Sunflower Oleosomes At The Air-Water Surface

Amin Aliyari1, Liam Ratcliffe2, Vincenzo di Bari1, David Gray1

1Department of Food Sciences, Sutton Bonington Campus, University of Nottingham, Loughborough, UK
2Unilever Research & Development, Colworth, Bedford, UK
The behaviour of fresh and heat-treated oleosomes at the air-water interface was measured. Oleosomes were recovered through a wet-milling process and went through different washing cycles to attain pure oleosomes. Washed oleosomes were dispersed in ultra-pure water and heat-treated (HT) at 75 °C for 5 min or kept as a non-heat-treated (Fresh). Protein concentration, and lipase activity of suspensions reduced with heating significantly. These changes seem to be associated with the loss of extraneous proteins after heating.

The behaviour of sunflower oleosome (Fresh and HT) preparations over a range of concentrations at the air-water interface was established by measuring their impact on surface tension using a force tensiometer. All oleosome preparations caused a reduction in the surface tension (ST); this reduction was more rapid and extensive with fresh RWOB. This observation, along the parallel measurements of the impact of the serum phase of these preparations, suggest that the presence of extraneous proteins cause a reduction in ST. Further studies using HT-RWOB (75 °C/5 min) revealed that there was a concentration dependent decrease in ST. The critical packing concentration was determined as 0.1% (w/v) based on fitting a model on oleosomes' ST behaviour. Particle size measurement and micrographs of emulsions before and after ST measurement indicate significant breakage and coalescence of oleosomes at higher concentration; while at lower concentrations, they acted mainly as pickering emulsions.