Effect of the amount of bites and orosensory exposure time on ad libitum intake

Sensory food properties are important for food intake regulation. For example,
solid foods were found to be more satiating than liquids. In literature, this
is mainly explained by the fact that liquids are consumed faster than solids.
First, liquids need less oral processing time and second, liquids are consumed
in larger sip sizes. Both effects result in less sensory exposure in the oral
cavity (orosensory) per gram food in liquids compared to solids. In addition,
studies that used controlled experimental designs showed us that the orosensory
exposure time is indeed important in satiation. However, the fact that solids
are consumed with smaller bites does not only lead to a larger exposure time
per gram food, but also means that more bites needs to be taken before an
actual amount of food is consumed. It is possible that also the amount of bites
contributes to satiation. Every time we take a new bite, means that we have a
new exposure in the mouth and that we have to swallow again. The effect of the
amounts of bites on satiation, apart from exposure time is not studied before
as far as we know.

The objective of this study to investigate the effect of the amount of bites
and orosensory exposure time, separately, on satiation (measured as ad libitum
intake).

A cross-over intervention study consisting of four treatments:
1.*short* condition: administration of 15g tomato soup in 3s (per 15s)
2.*long* condition: administration of 15g tomato soup in 9s (per 15s)
3.*shortbite* condition: administration of three times 5g in three times 1s
(per 15s)
4 *longbite* condition: administration of three times 5g in three times 3s (per
15s)

The total exposure time in the *short* and *shortbite* per 15 g will be equal:
3s in 15s
The total exposure time in the *long* and *longbite" per 15 g will be equal: 9s
in 15s

To investigate the effect of orosensory exposure time, the ad libitum intake of
the *short* conditions (index treatment) will be compared with the ad libitum
intake of the *long* conditions (reference treatment) (see Table 1 in protocol
for an overview).
In addition, to investigate the effect of bites, the ad libitum intakes of the
*shortbite* and *longbite* condition (index treatments) will be compared with
the ad libitum intake of the "short" and*long* condition (reference
treatment).

The study is non-therapeutic to the subjects. The risk associated with
participation is negligble and compared to other studies the burden can be
considered low.