Replacing solid fat in croissant dough using xanthan gum-based oleogels. Impact on rheological properties and final product quality

Healthier croissants prepared with xanthan gum-based oleogels have been evaluated by mechanical and sensory properties. Blends containing oleogel and conventional fat (shortening, SH) (50/50) were used as fat source in the croissant doughs. The shortening/oleogel (SH/OG) blends and doughs were rheologically characterized by Small and Large Amplitude Oscillatory Shear (SAOS-LAOS) tests, whereas both doughs and baked croissants were characterized by penetration and Texture Profile Analysis (TPA) tests. Acceptability and purchase intention tests of the selected croissants was also carried out, as well as discriminatory tests to confirm whether there were differences between the samples. Different oleogels were tried, combining four food structuring agents (whey protein (WP), polysorbate Tween (TW), soy lecithin (SL) and locust bean gum (LBG)) with xanthan gum (XG) in order to structure sunflower oil. Viscoelastic moduli presented differences depending on the structuring agent used in the oleogels. SH control was firmer than all blends. However, this pattern was not reproduced in the croissant doughs. The control dough, formulated only with the shortening had an intermediated behaviour in oscillatory shear. Indeed, in texture it presented the lowest values, with a hardness similar to that of the lecithin blend. However, doughs formulated with LBG or WP blends showed the highest values for both hardness and viscoelasticity. Baked croissants formulated with SL blend presented a crumb appearance and an airy structure similar to the control. Croissants formulated with the other blends were more compact and had higher hardness values. Therefore, formulation containing SL blend was selected for further analysis. Control and SL-based doughs followed the same pattern when large deformations were applied: shear stiffening and shear thinning behaviour. Regarding sensory analysis in final croissants, no differences in appearance, texture, flavour and overall liking were obtained. There was also no difference in purchase intention, so that the formulation with SL oleogels was optimal for the healthier croissants proposed.