Self-Assembly in Food – A New Way to Make Nutritious Products - Food Colloids: Self-Assembly and Material Science - page 21

Figure 1 Schematic phase diagram indicating the complexity of food structures based on
the three macronutrients: proteins, lipids (oils/fats) and polysaccharides
(carbohydrates). The centre triangle corresponds to the dry matter composition.
In the case of emulsifiers and proteins, addition of water produces a very
complex phase behaviour. On the same diagram, digestion behaviour can also be
represented if the water corner is replaced by an artificial digestion medium
(Copyright PhysChem Consulting (2006))
self-assembled aggregates, and developing an understanding as to how these
structures can be applied in form of colloids.
In this article we review important physico-chemical and colloidal aspects
regarding the digestion of lipids in relation to emulsion structure. Lipid diges-
tion is a rather complex process, resulting in different intermediate self-assem-
bled structures. We may consider emulsions as ideal systems for studying the
relationship between food structure formation and lipid digestion, because they
are easy to produce with different droplet sizes, and they can be created with
various internal self-assembled structures, resulting in cubosomes, hexosomes
and isasomes. 20-25 Moreover, emulsions can be loaded with lipophilic and
amphiphilic bioactives such as esterified and non-esterified plant sterols. Emul-
sions are also ideal model systems, as they can easily be exposed to artificial or
native digestion media such as saliva, gastric juices, lipolytic enzymes and bile.
2.2 Lipid Digestion - A Self-Assembly-Based Bioprocess
On average, the daily adult Western diet contains approximately 100 g of lipids,
of which 92-96% consist of long-chain triacylglycerols, also referred to as