2.1. Study Design
This study was a randomised, crossover design mastication study in healthy volunteers consisting of a single study visit with two mastication sessions. A mastication study is required as mastication has a key role in reducing PSD and reflects the presentation of almonds as they appear in the gut in vivo. It has been demonstrated that there is large inter-individual variability in masticatory parameters such as the number and duration of mastication cycles, and that PSDs are dependent on food type [Therefore, a within-subjects design was determined to be most appropriate to compare the PSDs and lipid bioaccessibility of whole and ground almonds. Randomisation was performed by an independent researcher, using the online randomisation website sealedenvelope.com (Sealed Envelope Ltd. 2020, London, UK). Participants were assigned to one of two sequences (whole almonds followed by ground almonds; ground almonds followed by whole almonds) in a 1:1 ratio. The sequence was concealed from researchers in sealed envelopes that were opened at the mastication study visit. Mastication sessions took place at the Metabolic Research Unit, King’s College London.