The aim of this study was to develop heat-induced gels of soy protein isolate(SPI)filled with Brazil nut oil emulsions encapsulating vitamin D3(VD3).Before gelation,dispersions produced with different SPI concentratio...The aim of this study was to develop heat-induced gels of soy protein isolate(SPI)filled with Brazil nut oil emulsions encapsulating vitamin D3(VD3).Before gelation,dispersions produced with different SPI concentrations(11-15%,w/w)were subjected to different pretreatments(manual mixing or mechanical stirring at 800 rpm for 10,20,and 30 min)and had their protein solubility quantified.The application of mechanical stirring increased the solubility of proteins and decreased the average particle size,affecting the microstructure(observed by confocal laser scanning microscopy)and rheological properties(evaluated by uniaxial compression and small strain oscillatory tests)of the heat-set gels.The incorporation of emulsions(produced with Brazilian nut oil)into gels formed emulsion filled gels(EFGs),which presented higher Young’s moduli andσH in comparison to non-filled gels(NFGs),indicating that the oil droplets were active within the matrices.The properties of EFGs subjected to small strain oscillatory tests,varied with the pretreatment conditions and SPI concentrations,highlighting the high influence of protein solubility,matrix inhomogeneities,and droplet clustering for determining the properties of such complex systems.Also,the heat-induced emulsion-filled gels of SPI produced were effective in protecting VD3,presenting good retention after 30 days of storage under refrigeration,and represent promising alternative for the production of future food gelled products.展开更多
We review how, starting from polymeric nanoparticles, to generate clusters of fractal morphology and to expand the entire space and interconnect to form gels, through either Brownian motion or intense shear-induced ag...We review how, starting from polymeric nanoparticles, to generate clusters of fractal morphology and to expand the entire space and interconnect to form gels, through either Brownian motion or intense shear-induced aggregation. In the case of Brownian motion-induced gelation, specific techniques developed to obtain uniform structure of gels under both reaction-limited and diffusion-limited cluster aggregation conditions have been described. In the case of intense shear-induced gelation as a newly developed technique, our focus is on its principle, theoretical development and advantages with respect to Brownian motion-induced gelation in practical applications. We consider gelation of both rigid and soft particles. As a physical process, the bonding between the particles within gels is owed to van der Waals attractions, thus being easily broken. However, in the case of soft particles that can coalesce upon contact, the coalescence can allow the particles to stick together forming permanent gels. In this case, the gel structure can be controlled by controlling the degree of coalescence. Techniques used to control the degree of coalescence have also been described.展开更多
基金CAPES(Conselho de Formacao de Pessoal de Nível Superior,Brazil,finance code 001)FAPESP(Sao Paulo State Research Foundation,grant 2017/06224-9)for the fellowships awarded to Letícia S.Ferreira and Thais C.Brito-Oliveira,respectively.
文摘The aim of this study was to develop heat-induced gels of soy protein isolate(SPI)filled with Brazil nut oil emulsions encapsulating vitamin D3(VD3).Before gelation,dispersions produced with different SPI concentrations(11-15%,w/w)were subjected to different pretreatments(manual mixing or mechanical stirring at 800 rpm for 10,20,and 30 min)and had their protein solubility quantified.The application of mechanical stirring increased the solubility of proteins and decreased the average particle size,affecting the microstructure(observed by confocal laser scanning microscopy)and rheological properties(evaluated by uniaxial compression and small strain oscillatory tests)of the heat-set gels.The incorporation of emulsions(produced with Brazilian nut oil)into gels formed emulsion filled gels(EFGs),which presented higher Young’s moduli andσH in comparison to non-filled gels(NFGs),indicating that the oil droplets were active within the matrices.The properties of EFGs subjected to small strain oscillatory tests,varied with the pretreatment conditions and SPI concentrations,highlighting the high influence of protein solubility,matrix inhomogeneities,and droplet clustering for determining the properties of such complex systems.Also,the heat-induced emulsion-filled gels of SPI produced were effective in protecting VD3,presenting good retention after 30 days of storage under refrigeration,and represent promising alternative for the production of future food gelled products.
基金Financial support from the Swiss National Science Foundation(Grant No.200020_147137/1)is gratefully appreciated
文摘We review how, starting from polymeric nanoparticles, to generate clusters of fractal morphology and to expand the entire space and interconnect to form gels, through either Brownian motion or intense shear-induced aggregation. In the case of Brownian motion-induced gelation, specific techniques developed to obtain uniform structure of gels under both reaction-limited and diffusion-limited cluster aggregation conditions have been described. In the case of intense shear-induced gelation as a newly developed technique, our focus is on its principle, theoretical development and advantages with respect to Brownian motion-induced gelation in practical applications. We consider gelation of both rigid and soft particles. As a physical process, the bonding between the particles within gels is owed to van der Waals attractions, thus being easily broken. However, in the case of soft particles that can coalesce upon contact, the coalescence can allow the particles to stick together forming permanent gels. In this case, the gel structure can be controlled by controlling the degree of coalescence. Techniques used to control the degree of coalescence have also been described.
