Core‐Shell Biopolymer Nanoparticles Produced by Electrostatic Deposition of Beet Pectin onto Heat‐Denatured β‐Lactoglobulin Aggregates

Abstract

The purpose of this study was to produce and characterize core-shell biopolymer particles based on electrostatic deposition of an anionic polysaccharide (beet pectin) onto amphoteric protein aggregates (heat-denatured beta-lactoglobulin [beta-lg]). Initially, the optimum conditions for forming stable protein particles were established by thermal treatment (80 degrees C for 15 min) of 0.5 wt% beta-lg solutions at different pH values (3 to 7). After heating, stable submicron-sized (d=100 to 300 nm) protein aggregates could be formed in the pH range from 5.6 to 6. Core-shell biopolymer particles were formed by mixing a suspension of protein aggregates (formed by heating at pH 5.8) with a beet pectin solution at pH 7 and then adjusting the pH to values where the beet pectin is adsorbed (< pH 6). The impact of pH (3 to 7) and salt concentration (0 to 250 mM NaCl) on the properties of the core-shell biopolymer particles formed was then established. The biopolymer particles were stable to aggregation from pH 4 to 6, but aggregated at lower pH values because they had a relatively small -potential. The biopolymer particles remained intact and stable to aggregation up to 250 mM NaCl at pH 4, indicating that they had good salt stability. The core-shell biopolymer particles prepared in this study may be useful for encapsulation and delivery of bioactive food components or as substitutes for lipid droplets.

Comparison of protein–polysaccharide nanoparticle fabrication methods: Impact of biopolymer complexation before or after particle formation

“…The particle size of the aggregates depends on the heating rate, heating duration [22], and protein concentration [23]. Complexation between these protein nanoparticles and anionic polysaccharides has been achieved with dextran sulfate [24] and sugar beet pectin [25] by reducing the pH towards the isoelectric point of the protein. We refer to the biopolymer particles created by addition of an oppositely charged polysaccharide to protein particles formed by heat treatment as ''Type 1 particles".…”

Beta-lactoglobulin–polysaccharide complexes as nanovehicles for hydrophobic nutraceuticals in non-fat foods and clear beverages

“…Another type of core-shell nanoparticles were recently proposed (Santipanichwong, Suphantharika, Weiss, & McClements, 2008) based on heat-denatured b-Lg aggregates (100e300 nm) coated by electrostatically deposited beet pectin. Other studies from that group investigated the effects of pectin type (high versus low methoxyl) (Jones, Decker, & McClements, 2010a, b), preparation conditions, like pH, ionic strength, protein concentration, heating time and temperature (Jones & McClements, 2010) and fabrication method, i.e., complex formation before or after heating (Jones et al, 2010a, b), on the properties of the particles formed.…”

Biopolymer nanoparticles designed for polyunsaturated fatty acid vehiculization: Protein–polysaccharide ratio study

“…As was mentioned above, in a BNP designed for PUFA vehiculization, the cover of polysaccharide on protein-ligand complexes could favour ligand protection against environmental factors (Jones et al, 2009(Jones et al, , 2010Santipanichwong et al, 2008;Zimet & Livney, 2009). In this last section, we have evaluated if HMP electrostatic deposition onto the surface of LA complexes could favour protection of the LA binding site.…”

“…As was mentioned previously, the strategy employed in this work for obtaining BNPs for LA vehiculization in acidic aqueous systems was: (1) BLG-LA complex formation, and (2) BNPs production via HMP electrostatic deposition onto the surface of the pre-formed BLG-LA complexes. The term 'polysaccharide electrostatic deposition' has been proposed by some researchers, suggesting the idea that the formation of a polysaccharide cover onto the surface of protein-ligand structure could promote the ligand protection against environment factors (Santipanichwong, Suphantharika, Weiss, & McClements, 2008). Additionally, this term could be interpreted as the formation of a protein-polysaccharide complex via attractive electrostatic interactions.…”