Project resumé: Lowfat dairy products – microstructure, sensory properties and consumer perceptionMichael Bom Frøst, Thomas Janhøj & Richard Ipsen
Copenhagen University, Department of Food Science
The goal of the project was to create a continuum of knowledge about lowfat dairy products spanning from the microstructural level and product composition, through human sensing of taste, aroma and texture, to consumers’ perception and appreciation.
Results from the project has led to an improved basic knowledge about which factors can be optimised to fully or partly replace the functionality of fat in different dairy products, while preserving good sensory properties. The project has been very successful in its exploration and description of relationships between the physical-chemical properties (incl. microstructure) and sensory properties. This has given a description of underlying physical properties necessary to preservation of creaminess in lowfat dairy products.
Studies with different types of lowfat dairy products have revealed that the relationship is system-dependent. In diluted (acidified milk drinks) and highly concentrated (cream cheese) systems a close and straightforward relationship between texture properties (viscosity, hardness, melt down) and creaminess was demonstrated. In weak gels (plain yoghurt), the relationship between structure and creaminess was more complex and also encompassed taste and flavour properties.
The project aimed at clarifying how individual senses contribute to the perception of complex products. In vanilla yoghurt we explored how vision and aroma (ortho- and retronasal) contributed to perception of creaminess. In contrast to the findings of others, our results with 40 untrained subjects showed that the creaminess ratings remained unchanged when both visual and olfactory inputs were excluded. This indicated that mouth feel and taste provided sufficient sensory input to allow reliable prediction of the absent input and thus more or less give the full percept of creaminess.
In consumer studies we have highlighted aspects of consumer experience. We investigated hedonic perception and its stability over exposures in vanilla yoghurts. Liking showed high stability at group level, while individuals may change their ratings dramatically.
1.Frøst, M.B. (2006) Liking and exposure: first, second and tenth time around, Physiology & Behavior, 89(1), 47-52 (doi:10.1016/j.physbeh.2006.01.036).
2.Frøst, M.B. & Janhøj, T. (2006) Understanding creaminess, submitted to International Dairy Journal.
3.Janhøj, T. & Ipsen, R. H. (2006). Effect of Pre-heat treatment on the functionality of microparticulated whey protein acid milk gels – Milchwissenschaft 61, 131-134
4.Janhøj, T.; Frøst, M.B. & Ipsen, R.H. (2006) Sensory and rheological characterization of acidified milk drinks, submitted to Food Hydrocolloids.
5.Janhøj, T.; Petersen, C.B.; Frøst, M.B. & Ipsen, R.H. (2006) Sensory and rheological characterization of low-fat stirred yoghurt, Journal of Texture Studies, 37(3), 276-299 (doi:10.1111/j.1745-4603.2006.00052.x)
6.Johansen, S.M.B.; Laugesen, J.L.; Ipsen, R.H.; Janhøj,T.; & Frøst, M.B (2006) Prediction of sensory properties of low-fat yoghurt and cream cheese from surface images, submitted to Food Quality and Preference.
7.Johansen, S.M.B.; Laugesen, J.L.; & Frøst, M.B (2006) Angle Measure Technique: Algorithms and Systematic Examination of Method Performances, submitted to Journal of Chemometrics.
8.Rasmussen, M.A.; Janhøj, T. & Ipsen, R.H. (2007) Graininess in lowfat yoghurts - Milchwissenschaft, in press |
