The research, published in Food Quality and Preference, suggests that the way we break foods down in our mouths (mastication) could be affected by complicated multi-ingredient (heterogeneous) foods - that contain more than one food component in a different matrix.
“This study shows that when heterogeneous test foods are chewed, the properties of one food component can influence the breakdown of another food component,” said the researchers, led byScott Hutchings, from the Institute of Food, Nutrition and Human Health, at Massey University, New Zealand.
The authors said that as such, the altered break down of foods could lead to altered consumer perceptions of textures and flavours.
“An understanding of the dynamics and particulate outcome of the oral processing of heterogeneous foods may allow food manufacturers to develop foods for sensory and nutritional benefits,” they added.
The researchers said that research into the mechanisms of chewing and mastication typically use foods of similar make up, to simplify the dynamics modelling process and the measurements of food bolus particle size distribution.
But, Hutchings and colleagues noted that mastication often involves the breakdown of more than one food type in the mouth; adding that many commercially available foods are heterogeneous (containing many different components) – for example muesli bars: which contain oats, raisins, and nuts that are chewed together.
“Currently, little is known about physiological responses or the mechanical outcome when heterogeneous foods are masticated and swallowed,” said the authors.
In particular, they said that different types of particle may be caught between opposing teeth surfaces at the same time during chewing, which may influence the mastication process by altering the duration or force applied during the chewing cycle.
Optimising chewing behaviour and the particle size distribution of the food bolus may benefit the glycaemic response, amino acid assimilation, texture perception, and the extent of flavour release, said Hutchings and his co workers.
“The aim of this study was therefore to investigate mastication and particle size outcome when a series of simple heterogeneous foods are chewed,” they said.
“We investigated chewing behaviour and particle size outcome in the oral processing of heterogeneous foods using peanuts embedded within two types of food matrices.”
Volunteers were served four model foods – each of which was comprised one of two matrices (chocolate or gelatine gel) embedded with one of two physically different particles (moist or dry peanuts).
The researchers reported that properties of the matrix caused differences in mastication (measured in terms of the number of chews, chewing duration, and frequency) and broadness of the peanut particle size distribution, but did not influence the final average size or distribution of the peanuts.
Hutchings and colleagues said that their results suggested that properties of the food matrix can influence the breakdown of food components in that matrix.
More specifically, they said that when heterogeneous foods are chewed, the properties of the matrix may influence the mastication of embedded solid particles.
“It is likely that properties of the matrix influenced the rate at which particles of various sizes were selected for chewing (known as the selection function), whereas the physical properties of the peanuts influenced extent of breakage when the teeth made contact with the particles (known as the breakage function),” said the authors.
Source: Food Quality and Preference
Published online ahead of print, doi: 10.1016/j.foodqual.2010.12.004
“Mastication of heterogeneous foods: peanuts inside two different food matrices”
Authors: S.C. Hutchings, K.D. Foster, J.E. Bronlund, R.G. Lentle, J.R. Jones, M.P. Morgenstern