Solid cheese consumption: quantification of oral coating.

Mouth coating, defined as the residual food that sticks to the oral surface after food ingestion, plays an important role in both the delivery of food components and mouth feel and after-feel perceptions. The aim of this work was to adapt a rapid and simple instrumental method to the quantification of food remaining after the in vivo ingestion of a solid food. This method was investigated in 12 non-trained subjects who consumed four melted cheeses differing in terms of their fat and water contents. Mouth coating was determined by fluorescence measurements using curcumin, an oil-soluble dye that had been added to the cheeses during their preparation. The results obtained showed that this method was reproducible, reliable and discriminating and could be used for solid cheeses covering a broad range of textures.

Saliva electrophoretic protein profiles in infants: changes with age and impact of teeth eruption and diet transition.

OBJECTIVE: The objective of this study was to describe the changes in salivary protein profiles in infants between the ages of 3 and 6 months, and to evaluate the impact of teeth eruption and introduction of solid foods on such profiles. DESIGN: 73 infants were followed longitudinally at 3 and 6 months of age. Their whole saliva proteins were separated by SDS-PAGE electrophoresis and semi-quantified by image analysis. Amylase activity was also measured on a sub-sample of the population (n=42 infants). Bands which abundance was significantly different between the two ages according to paired comparisons were identified by mass spectrometry techniques. RESULTS: Out of 21 bands, 13 were significantly different between 3 and 6 months of age. Two short variants of amylase increased in abundance with age, as did amylase activity. Other changes possibly translated developmental physiological events, for example maturation of the adaptive immune system. The balance between S-type cystatins and cystatins A and B was modified, in favour of S-type cystatins at 6 months of age. Teeth eruption resulted in an increase in albumin abundance, whilst introduction of solid foods was associated with higher levels of ß-2 microglobulin and S-type cystatins. CONCLUSIONS: Salivary profiles were modified substantially between the ages of 3 and 6 months. Both teeth eruption and diet had an impact on abundance changes for some proteins, revealing dynamic interactions between saliva proteome, oral physiology and diet.