Relating creamy perception of whey protein enriched yogurt systems to instrumental data by means of multivariate data analysis.

UNLABELLED: Yogurts differing in fat content, protein content, and casein to whey protein ratio were produced, and structurally as well as sensorially examined. The objective of the current research was to evaluate the predictive value of rheological and particle size measurements concerning sensory appearance and texture attributes in 13 differently composed stirred yogurt systems, with a focus on graininess, viscosity, and creaminess. Structural and sensory analyses showed large differences in texture properties between the tested yogurt systems. Both data sets were correlated by means of multivariate statistical methods. Sensory graininess was highly correlated with particle size-related parameters, sensory viscosity was highly correlated with destructive rheological parameters, and creamy perception was highly correlated with particle size-related parameters and destructive rheological parameters but was not as well described by any oscillatory parameter. Best predictive ability (r(2) > 0.89) was found for creaminess combining particle size related- and destructive rheological parameters tested within this study. PRACTICAL APPLICATION: Knowing the instrumental parameters describing sensory textural attributes provides important information for having a better understanding of the underlying processes during consumer's perception. Knowledge about the sensory behavior of a product and its oral processing imparts an opportunity to fasten the product development process. By means of yogurt systems instrumental parameters derived from particle size analysis and rheological measurements were correlated with sensory attributes in order to determine the main factors leading to the mouthfeel sensations grainy, viscous, and creamy of semisolid milk products.