*3.4. Sensory Evaluation*

The results of sensory analysis obtained for control bread and breads enriched with Yg (A) and Cc (B) are given in Figure 6. Appearance, flavor, crust color, aroma, texture, and overall acceptability of breads with 30 g and 50 g of both dairy products significantly differ in respect to control bread (0 g/100 g).

**Figure 6.** Sensory profile analysis of breads enriched with yoghurt (**A**) and curd cheese (**B**), with 30 g and 50 g of addition, compared with control bread (0 g/100 g).

Considering the Yg breads (Figure 6A), higher levels of yoghurt addition (50 g) caused a pleasant lactic aroma, taste, and crust color, with a significant positive influence on bread acceptability. This bread scored 5 for all attributes. In terms of texture, this Yg bread was classified as more crunchy, softer, and had a good alveoli distribution compared to the other breads (0 g and 30 g).

The best preference of Cc breads (Figure 6B) was obtained to 30 g of Cc addition, with a good acceptability in overall sensory attributes, and classified as having a better taste, crust color, and aroma. This bread also scored 5 for all attributes. For higher concentration tested (50 g), the excessive amounts of Cc proteins negatively affected the texture of this bread and the alveoli distribution, which influenced their sensorial acceptability. Results of sensory characteristics indicated that a partial replacement of wheat flour by 50 g of Yg and 30 g of Cc gave satisfactory overall consumer acceptability, and with respect to purchase intention, these breads were the best classified as "would buy for sure."

#### **4. Conclusions**

From the results of this work, it can be stated that all incorporations of the Yg resulted in good bread quality properties, and no significant adverse effect on texture and aging bread kinetics was observed. However, for Cc additions, from 30 g of Cc on, a significant increase of the crumb firmness and the aging kinetics was registered. The microstructure analysis supported the results obtained for the dough rheology and bread texture.

Considering nutritional composition, a significant increase in mineral contents was observed, indicating that the Yg and curd Cc can be used as nutritional and functional ingredients in bread formulations, which can have a significant impact on well-being. In terms of lipid content and based on higher levels to be considered as bread quality, the increase on Yg bread (50 g) was not significant, on the order of 28%, compared to control bread. However, for Cc breads (30 g), the increase in fat was much higher, around 168%, and these lipids coming from milk are mainly saturated fatty acids.

The incorporation of both dairy products studied were demonstrated to be an interesting alternative on the design of new bakery goods, with both technology properties and sensory acceptability. In terms of nutritional profile, Yg and Cc additions presented a considerable contribution to balance the daily diet, especially for children and seniors, in terms of protein, as well as in major and trace minerals, which are important to human health. However, the curd cheese addition promoted a significant increase in lipid content, which can constitute a limitation.

**Author Contributions:** C.G., conceived and planned the experiments; performed all samples preparation and analysis, data analysis, and interpretation of the results: and wrote the manuscript. A.R. and I.S. supervised the research work, contributed to the discussion of the data, and revised the manuscript.

**Funding:** This work was funded by the University of Lisbon (Doctoral Grant reference to C10781w) and by the Portuguese Foundation for Science and Technology (FCT) through the research unit UID/AGR/04129/2013 (LEAF—Linking Landscape, Environment, Agriculture and Food).

**Conflicts of Interest:** The authors declare no conflicts of interest.

## **References**


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