A novel in vitro framework for understanding aroma interactions with the oronasal mucosa

An overview is presented of the olfactory mucosa, volumetric air flow through the geometry of the nasal and oral cavity and a review of the constituent parts of oro-nasal surfactants, saliva and nasal mucus. Discussed is the physical chemistry of dictating the behaviour of aroma in aqueous solutions...

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Bibliographic Details
Main Author: Ford, Clive
Format: Thesis (University of Nottingham only)
Language:English
Published: 2022
Subjects:
Online Access:https://eprints.nottingham.ac.uk/69550/
Description
Summary:An overview is presented of the olfactory mucosa, volumetric air flow through the geometry of the nasal and oral cavity and a review of the constituent parts of oro-nasal surfactants, saliva and nasal mucus. Discussed is the physical chemistry of dictating the behaviour of aroma in aqueous solutions. Previous investigations into the techniques deployed to describe aroma interactions with proteins, lipids, and biological system such as the oro-nasal mucosa. A review on the theory and use of APCI-MSMS, an analytical instrument used for real time detection of volatilised aroma through the MS NOSE interfaces. An overview is provided on the development of a novel volatile delivery system for the real time injection of volatilised aroma samples to air-solution interfaces housed within custom reaction vessels. A chapter discussing the sensitivity gains achievable in APCI analysis by adopting a dual mass filtering approach using MRM techniques, validation of isobaric resolution is also presented for in vitro and in vivo systems, including a novel method for persistence of inhaled volatiles, a previously unseen use of APCI. Gas phase aroma deposition techniques are compared with dynamic headspace techniques for model lipid emulsion systems to highlight the developed techniques applicability in the investigation into interfacial aroma interactions with a medium of interest. In vivo aroma deposition data is compared with in vivo solution persistence of aroma and parallels are drawn between the two systems through robust statistical analysis. Investigations consider the impact of mucin on aroma absorbance and release under shear stress and after modulation by salt. Absorption kinetics are a new topic for discussion not fully explored in the literature as is the identification of mucin induced Marangoni effects, that is the homogenisation of aroma absorption caused by surface tension gradients. Finally, mass transfer and surface permeability are used to explain some of the observed aroma-mucin interactions in vitro.