ISBN 978-3-8439-1901-2

978-3-8439-1901-2, Reihe Lebensmitteltechnologie

Alina Sonne
Micro- and macro-structural matrix properties as modulator for creamy perception in yogurt systems

178 Seiten, Dissertation Universität Hohenheim Stuttgart-Hohenheim (2014), Softcover, A5

Zusammenfassung / Abstract

In this thesis, a comprehensive research approach for understanding textural and physiological aspects of fat perception of semi-solid dairy products is provided. Therefore, the objective of this study was to assess yogurt texture instrumentally in order to deduce modulators for creamy perception and subsequently to adjust micro- and macro-structural properties of low-fat yogurt systems towards high creamy sensation. The structural and sensory properties of yogurt systems as affected by formulation (fat, protein, and casein to whey protein ratio) were examined. Physical methods, capturing the dynamic aspects during oral processing, were established and covered textural characteristics of yogurt systems to a high extent. Thus, the multi-sensory experience of creaminess can be mapped by combined assessments of rheology, particle size, and tribology characteristics. The link between instrumental to sensory data displayed texturizing elements for the development of fat-reduced yogurts and main factors that lead to the mouthfeel sensations grainy, viscous, and creamy. Based on these results, two texturally comparable creamy yogurt systems with 8% fat and without fat were developed and used as a test matrix for assessing the hedonic response of the human brain to milk fat by means of a satiety study. Different response of the fat content of yogurt on the blood flow in hypothalamus and insular cortex was obtained and hence indicated that fat might be a modulator of homeostatic and gustatory brain regions. And finally, identified textural modulators were integrated into a proof of concept, testing the performance of whey protein-pectin microparticles to replace parts of fat in terms of yogurt structuring and sensory qualities. Whey protein-pectin microparticles implemented into a low-fat yogurt matrix enhanced textural sensations to those of full-fat counterparts.

This comprehensive research approach provides insights in terms of designing food structures and thus modifying food texture towards high creamy sensation within the range of fat-reduced semi-solid dairy products with an efficient energy homeostasis.