Improving texture perception in low-fat high-protein yogurts thanks to whey protein aggregates

Hanna Lesme (1) , Cecile Rannou (1) , Catherine Loisel (1) , Clémence Alleaume (1) , Marie-Hélène Famelart (2) , Said Bouhallab (2) , Carole Prost (1)

1 GEPEA - Laboratoire de génie des procédés - environnement - agroalimentaire
2 STLO - Science et Technologie du Lait et de l'Oeuf

The demand for low-fat high-protein yogurts has increased substantially over the past years. However, manufacturing protein rich yogurts often results in rubbery mouthfeel and firmer products. Whey proteins are denatured during heating of milk leading to the formation of whey protein aggregates (WPA) able to interact with caseins during acidification. The rise of whey protein concentration in yogurts comes along with a tighter and denser protein network which can be detrimental for texture perception. The objective of this study is to produce targeted WPA from native Whey Protein Isolate (WPI) through a controlled process to obtain protein-rich yogurts with satisfying texture properties. In the present study, low fat set style yogurts were prepared adding three concentrations of extra WPI or targeted WPA. Either monodisperse or polydisperse WPA populations were studied. Sensory characteristics of these nine yogurts were assessed by free sorting by naïve panelists (n=32). Texture perception was related to rheological properties and instrumental texture measurements of yogurts. Sensory results clearly showed that the addition of WPI and WPA increased yogurt firmness. Most interestingly, it appeared that for the same concentration, the type of whey protein added had a significant impact on texture perception. Yogurts enriched in WPA were described as creamy and unctuous whereas yogurts enriched in WPI were brittle and compact. The rheological results, and in particular the flow measurement parameters confirmed this trend. Moreover, using monodisperse small WPA instead of polydisperse WPA was a way to increase yogurts’ firmness while keeping unctuousness. Incorporating WPA in low-fat high-protein milks is a promising way to modulate texture perception of yogurts. This is interesting to develop fresh dairy products with special functional properties while maintaining a good sensory experience for the consumers. Further research could focus on high-protein yogurts with desirable texture properties for the elderly.

Mots clés: protéine de lait; matière grasse; sensorial perception; whey paste; yoghurt; casein

Mots clés: perception sensorielle; acidification; lactosérum; agrégat protéique; yaourt; caséine; texture

Domaines: Alimentation et Nutrition; Ingénierie des aliments

Hanna Lesme, Cecile Rannou, Catherine Loisel, Clémence Alleaume, Marie-Hélène Famelart, et al.. Improving texture perception in low-fat high-protein yogurts thanks to whey protein aggregates. 5. International Conference on Food Oral Processing, Jul 2018, Nottingham, United Kingdom. , 2018. ⟨hal-01887272⟩