Chemistry Reference
In-Depth Information
9
Protein-Stabilised Emulsions and
Rheological Aspects of Structure
and Mouthfeel
Fotios Spyropoulos, Ernest Alexander K. Heuer,
Tom B. Mills and Serafim Bakalis
9.1
INTRODUCTION
Emulsions are an integral part of many food products. In the past, re-
search in emulsion-based systems focused mainly on understanding
the mechanisms of formation and stabilisation of these systems. More
recently, efforts have been devoted towards obtaining an understand-
ing of the behaviour of emulsion-based foods during oral processing
('eating'), aimed at designing novel functional products that deliver
advanced health benefits.
There is evidence that such health benefits can indeed be achieved
from food formulations, especially in order to tackle issues such as
the obesity crisis (Norton, Fryer,
et al
., 2006). As obesity has reached
epidemic levels in the Western world, it is clear that calorifically dense
foods, such as (high-fat) emulsions, have to be redesigned. In order to
achieve this, an understanding of the phenomena occurring in-mouth as
well as their link to consumer perception would have to be obtained. In
the past, research in this area was mainly driven by medical sciences
and focused on understanding some of the fundamental mechanisms
of transport within the body; for example, movement of the bolus and
identification of some relevant forces in the mouth. Work on physical
characterisation and
in vitro
measurements of the physical and structural
changes that food emulsions (and food in general) experience during
oral processing is now becoming more widespread. If perception and
sensory properties of a product can be related to these instrumental
measurements, improvements can be made much faster and without the
need for human subjects. Current work in the field of emulsions has
been promising, especially when relating important key attributes such
as creaminess or slipperiness to on-board friction measurements carried
out on instruments (tribology).
