Figure 4 shows an example of how nanolaminates could encase
food objects. The object to be coated with a nanolaminate would be
dipped into a series of solutions containing substances that would
adsorbto the surface of the object(McClementsandothers 2005). Alternatively,
the solutions containing the adsorbing substances could
be sprayed onto the surface of the object. The composition, thickness,
structure, and properties of the multilayered laminate formed
around the object could be controlled in a number of ways, including
(i) changing the type of adsorbing substances in the dipping
solutions; (ii) changing the total number of dipping steps used;
(iii) changing the order that the object is introduced into the various
dipping solutions; or (iv) changing the solution and environmental
conditions used, such as pH, ionic strength, dielectric constant,
temperature, and so on. The driving force for adsorption of a substance
toasurfacewoulddependonthe natureof the surfaceandthe
nature of the adsorbing substance. The force itself could be electrostatic,
hydrogen-bonding, hydrophobic interactive, thermodynamically
incompatible, and so on, but it would usually be electrostatic
attraction of oppositely charged substances. The influence of the
properties of the substrate surface—such as topology and roughness
on the structure of the nanolaminates that are built on the
substrate surface—has not yet been established. It is possible that
nonuniform laminates could be formed that contain microscopic
and macroscopic pores that could negate the barrier function of
the laminate. Consequently, this would necessitate the formation
of a second base biopolymer layer on the food product to form a
more uniformsubstrate surface, followed by deposition of the layer
containing the functional ingredient