## 3 Results and Discussion
### Rheological Properties of the Doughs
Figure 4: Mixolab curves of the dough samples prepared with: (**a**) white wheat flour (WF); (**b**) WF supplemented with sunflower oil (SO); (**c**) WF supplemented with soy protein-based emulsion (SE); (**d**) WF supplemented with lupin protein-based emulsion (LE); (**e**) WF supplemented with yeast protein-based emulsion (YE). The thermo-mechanical behavior of the doughs prepared with emulsion instead of oil varied with the type of proteins used to prepare the emulsion. The maximum torque of the doughs prepared with soy and lupin proteins registered during mixing at a constant temperature of 30 \({}^{\circ}\)C were 0.15 Nm and 0.06 Nm, respectively. In the case of both samples, the gradual drop of the torque to zero was noticed during the initial mixing at 30 \({}^{\circ}\)C (Figure 4c,d). The more rapid decrease of the torque, compared with the dough sample prepared with sunflower oil, might be due to the fact that the lipids in the fine oil drops within the emulsion are more easily available for interacting with the macromolecular components of the wheat flour, resulting in faster termination of the adhesion between the mixing paddles and dough. A sharp increase of the torques was noticed when the temperature increased to 85-87 \({}^{\circ}\)C, the maximum C3 value of 0.46 Nm, registered for doughs with soy and lupin protein emulsions, being higher compared with the oil-based dough. These results suggest a better gelatinization of the starch as a consequence of a lower volume fraction of oil when emulsions are used to prepare the doughs. The lower C4 values registered for doughs prepared with soy and lupin proteins-based emulsions suggest the lower hot paste stability compared with the oil-based sample. Cooling the doughs to 50 \({}^{\circ}\)C in the final Mixolab stage resulted in the C5 values of 0.69-0.71 Nm, close to the one registered for the oil-based sample. These results indicate higher starch retrogradation in the case of the samples prepared with soy or lupin proteins emulsion (C5-C4 of 0.52-0.53 Nm) compared with the oil-based dough (C5-C4 of 0.47 Nm). In addition to oil, which exerts a major influence on the starch-related thermo-mechanical behavior of the doughs, the starch swelling and gelatinization are hampered by the interactions established by the proteins originating from the emulsion. [PERSON] et al. [31] explained this phenomenon by the perturbation occurring in the hydrogen bonding network. Furthermore, the non-covalent interactions established between the gelatinized starch and the proteins are prone to alter the retrogradation behavior of the starch [28]. A different trend was observed in the case of the sample containing yeast proteins emulsion (Figure 4e). Analyzing the results presented in Table 2, one can see that, except for C5, all torque values were higher compared with the wheat flour dough. This particular rheological behavior is a consequence of the higher amount of water needed to prepare the dough of a specific work input (corresponding in this case to C1 of 1.1 Nm), which is due to the particular composition of the yeast extract used to prepare the emulsion. In addition to the high protein content, the yeast extract is particularly rich in minerals and B-complex vitamins. [PERSON] et al. [14] obtained lyophilized yeast extract with a protein content of 64% and high levels of macrominerals, trace elements (1.76 mg Fe/100 g dw and 11.9 mg Zn/100 g dw), and vitamins like nicotinic acid (77.2 mg/100 mg dw) and folic acid (3.01 mg/100 g dw). Moreover, [PERSON] [15] indicated that yeast extract is a good source of minerals (such as Ca over 130 mg/100 g dw and Fe over 5 mg/100 g dw) and group B vitamins (such as thiamine 10-12 mg/100 g dw, riboflavine 8-12 mg/100 g dw, niacine 90-110 mg/100 g dw, and pantothenic acid 12-20 mg/100 g dw). The human body needs all these micronutrients, and their adequate intake and availability are particularly important for a healthy lifestyle.