Mastication of Carrots with Different Shapes Affects the Composition of the Salivary Proteome—A Pilot Study

Chewing is a sensorimotor activity that aims to prepare food for swallowing, in which saliva intervenes, moistening food particles, assisting in bolus formation, enzymatic digestion, and swallowing. This study investigated the effect of chewing carrots of different shapes on salivary secretion and protein profiles using 2-DE gel electrophoresis. Fifteen participants chewed sliced or grated carrots, or parafilm (non-food control), in a crossover design, with saliva samples collected before and after mastication. The results showed significant differences in salivation and saliva composition when chewing carrots vs. the control, with sliced carrots inducing greater changes: 37 protein spots, including amylase and immunoglobulin spots, 9 protein spots, and 1 protein spot were significantly altered after chewing sliced carrots, grated carrots, and parafilm, respectively. Mastication combined with the sensory properties of food had a greater effect on saliva secretion and salivary protein levels than mastication alone. Among carrot shapes, the results suggest that harder food textures, which require more chewing effort, lead to more pronounced changes in salivary protein profiles. These findings contribute to the understanding of how food shape and texture influence salivation and salivary proteome dynamics, with potential implications for oral digestion, food-related sensory experiences, and the personalisation of diets for individuals with a compromised chewing capacity.