The investigators want to understand how oral processing (chewing) of nuts affects particle size and the presence of lipid (fat) on the cut surfaces.

The main objective of the study is to:

Measure the size of nut particles that have been chewed sufficiently to be swallowed.

The secondary objective of this study is to:

Measure any changes in lipid content due to chewing and compare it to a prediction from a theoretical model.

The investigators have developed a theoretical model for determining the release of nutrients from plant foods, specifically lipid (fat) from almonds. The model has been used to calculate the amount of lipid released from chewed almonds. The model shows that only about 10% of the lipid is immediately released. The investigators require information on the particle size distribution (number of particles of each size) for other chewed nuts to calculate the amount of lipid released for other nuts. This will allow us to check the validity of our model for other foods.

Inclusion Criteria:

• Must be generally healthy
• Must have eaten nuts within the last month with no adverse effects

Exclusion Criteria:

• Must not be allergic to nuts of any kind
• Must not have any teeth missing (apart from unerupted wisdom teeth)
• Must not have bleeding gums
• Must not have had dental treatment (other than checkups) in the last 3 months
• Must not be currently suffering from any infectious disease that may be passed on via saliva e.g. Glandular fever, flu