albumin (BSA) and casein, as the main protein fraction in milk, offers more than a
simple functional agent in dairy technology. They possess a great potential in complex
formation and encapsulation of nature flavor as biocompatible polymers [7].
BSA are a group of acidic proteins, which occur plentifully in the body fluids and
tissues of mammals and in some plant seeds. Unlike globulins, albumins have
comparatively low molecular weights, are soluble in water, are easily crystallized, and
contain an excess of acidic amino acids. BSA binds water, Ca
2+
, Na
+
, and K
+
. Due to a
hydrophobic cleft, albumin binds fatty acids, bilirubin and other bioactive compounds.
Complexation of BSA and the natural anionic polysaccharide–furcellaran (FUR)
has been studied in the broad range of their concentration ratio and pH of the solutions.
The nanocapsule shells were formed by the layer-by-layer adsorption of
polyelectrolytes; polycation PDADMAC (polydiallyl dimethyl ammonium chloride)
and polyanion PSS poly(sodium-4-styrene sulfonate). Depending on the shell
thickness, the size of the nanocapsules was in the range of 60–80 nm [8].
Casein (derived from the Latin caseus for ‘cheese’) [9] is the collective term for
a family of secreted calcium (phosphate) binding phosphoproteins found in mammalian
milk [10]. Caseins, in contrast to the second milk protein fraction, i.e. whey proteins,
are insoluble and account for 80 % of total bovine milk proteins [11, 12] which
translates to 2.75 % of total milk components.
Caseins were found to interact with polysaccharides, forming coacervate-type
complexes [13, 14]. The coacervation method was reported to be suitable for
encapsulation of volatile compounds [15, 16]. After mixing sodium caseinate or whey
protein isolate with carboxymethyl cellulose, β-pinene was added and oil-in-water
emulsions were prepared. Coacervation has been conducted at pH 2.8. Higher protein-
to-polysaccharide ratio was more beneficial through the formation of a network in
which β-pinene could be entrapped, being more evident in the case of whey proteins,
supposedly due to partial unfolding at low pH [15].
Interaction of caseins with other polymers was another process used for
preparation of nanoparticles. Casein–pectin polyelectrolyte complexes have been
fabricated by slow acidification with glucono-d-lactone and heating. The obtained
nanoparticles have been used to encapsulate eugenol and thymol before spray-drying
[17].
Nanoemulsions from polymeric nanoparticles may possess a relatively high
kinetic stability even for several years, due to their very small size, essentially the
consequence of significant steric stabilization between droplets. They have droplet
covering the size range of 10 –500 nm and referred to as mini-emulsions, ultrafine
emulsions, emulsoids, unstable microemulsions and submicrometer emulsions [5]. The
association of EO with polymeric nanoparticles presents several advantages; controlled
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