Properties of microparticles from a whey protein isolate/alginate emulsion gel

Abstract

Designing soft, palatable and nutritious texture-modified foods for the elderly is a challenge for food technologists. The aim of this work was to produce and characterize emulsion-gelled microparticles (EGM) made from whey protein isolate (WPI) and sodium alginate (NaAlg) that may be used to modify the rheology of liquid foods and as carriers of lipids and lipophilic nutrients and bioactives. Olive oil microdroplets became embedded in the WPI/NaAlg gel matrix in the form of an emulsion produced by ultrasound (US) or high-speed blending (HSB). Oil microdroplets were obtained by US and HSB, with an average equivalent diameter varying between 2.0-3.2 µm and 4.5-6.7 µm, respectively. Oil incorporation increased compression stress of bulk emulsion gels at small deformations compared to the no-oil microgel, but this effect was reversed at high strains. EGM were prepared by shear-induced size reduction. Rheological tests at 20 ℃ and 40 ℃ showed that US-EGM and HSB-EGM exhibited a predominant elastic behavior, with G' > G″ throughout the frequency range. However, when HSB-EGM were heated at 60 ℃ their rheological behavior changed to a more fluid-like condition, but not that of US-EGM. Consequently, EGM have the properties needed to improve food texture for people with masticatory/swallowing dysfunctions or needing special nutrition.

Preparation, structure-property relationships and applications of different emulsion gels: Bulk emulsion gels, emulsion gel particles, and fluid emulsion gels

“…Fluid emulsion gels can also be prepared by breaking down bulk emulsion gels (Leon, Medina, Park, & Aguilera, 2018). Soukoulis, Cambier, Hoffmann, & Bohn (2016) investigated so-called sheared oil-in-gel (o/g) emulsions prepared by stirring an alginatebased emulsion gel system at 1000 rpm for 6 h during the gelation process.…”

Structural and foaming properties of whey and soy protein isolates in mixed systems before and after heat treatment

“…Protein-rich ingredients are widely used by food industries in formulated food products due to their nutritional relevance and useful techno-functional properties (Kazmierski and Corredig, 2003). Ingredients containing high amounts of whey proteins (WP), such as the whey protein isolate (WPI), have been seen as key components for food formulation due to their high solubility, good interfacial activity and large scale of production (de Castro et al., 2017; Kilian et al., 2020; Leon et al., 2018; Nunes and Tavares, 2019). β-lactoglobulin (β-LG) and α-lactalbumin (α- LA) are the major WP, representing around 55% and 20% of the total protein content of whey, respectively (Nunes and Tavares, 2019).…”

Emulsion gels as delivery systems for phenolic compounds: Nutritional, technological and structural properties

“…Novel emulsion-based strategies, such as emulsion gels, could also be alternatives with great potential as delivery systems and to preserve the functional properties of phenolic compounds. Different emulsion gels have been developed as delivery systems for specific compounds with potentially beneficial health effects, such as oleic acid, alpha-linolenic acid, dietary fibre and minerals (Paradiso, Giarnetti, Summo, Pasqualone, Minervini, & Caponio, 2015;Pintado, Ruiz-Capillas, Jimenez-Colmenero, Carmona, & Herrero, 2015;Pintado, Herrero, Jimenez-Colmenero, & Ruiz-Capillas, 2016a;Leon, Medina, Park, & Aguilera, 2018;Herrero, Ruiz-Capillas, Pintado, Carmona, & Jimenez-Colmenero, 2018;Paglarini, Martini, & Pollonio, 2019). Those emulsion gels, in addition to their beneficial nutritional properties, have presented optimal technological properties due to their gel-like network structures and solid-like mechanical properties.…”