## 4 Discussion
### Bread Yield and Color  
An important parameter indicating the quality of the baked product is its final volume, which is related to the entire technological process, but mainly to the amount and quality of protein, especially gluten [43]. The addition of THY and LMG essential oils to the recipe did not lead to a significant reduction in volume yield compared to the control. The concentrations tested ranged from 0 to 80 mg/100 g of flour. [PERSON] et al. [31] reported a negative effect of thyme essential oil on bread volume from a concentration of 137.55 mg/100 g flour (172% of own maximal dose). Lower concentrations had no damaging effect on the specific volume of the bakery product. According to [PERSON] et al. [44], dried thyme positively impacted bread quality when supplemented even up to 2% of flour. This was evident in the increased specific volume values at 1% and 2% supplementation levels. On the other side, spices and herbs such as cinnamon, clove, garlic, oregano, and thyme, added at 1 or 2%, significantly decreased the bread volume [45]. Lemongrass essential oil is well known for its strong antimicrobial activity against fungi, yeasts, and bacteria [46]. There is a presumption of yeast inhibition and as a result of the reduction in fermentation, the volume of bread may be reduced [31]. The observed \(L^{\star}\) values for the crust were measured from 59.0 to 69.8, which is a standard range determined by many other authors [47]. The values for \(a^{\star}\) ranged from 8.79 to 15.70 and \(b^{\star}\) from 32.98 to 38.33 indicating the crust color of elaborated breads fell within the red-yellow area, which is a favorable characteristic of baked goods for consumers. [PERSON] et al. [48] used white wheat all-purpose flour, produced in New Zealand, and tested wheat bread fortification by wholeemafba bean flour and protein isolate. Their control wheat bread had similar \(L^{\star}a^{\star}b^{\star}\) color coordinates ([59.9; 13.1; 31.3] for crust and [70.22; 2.07; 19.18] for crumb) as the own control (STD). The addition of 20 wt.% of both faba bean forms changed the color of wheat bread crust significantly on all three axes of the color space--the evaluated coordinates were [45.5; 16.5; 29.5] and [31.2; 15.0; 17.9], respectively. The authors explained bread browning, reddening, and yellowing as just a result of the Maillard reaction, speeded up by a higher content of legume proteins. The color of the crust and crumb are quality parameters, which are associated with the organoleptic properties of the bread [49], and these attributes hold significance from the perspective of the customers. Caramelization and Maillard reaction led to the development of non-enzymatic browning in baked goods surface (resulting in its attractive flavor and beige-brown color). Reducing sugars react with an amine, creating via glycosylamine a derivate of amino deoxy-Tructose. Our results indicate that the addition of EO to the recipe did not manifest itself in a large and consumer-unfriendly way. For example, the addition of protein-rich plant materials, e.g., chickpea powder, supports crust browning. Replacing 5.0, 17.5, and 30.0 wt.% of wheat flour, the \(\Delta E\) has risen from 24.9 and 30.2 up to 34.1, respectively [50]. The total color difference \(\Delta E\) can be classified analytically according to [PERSON] et al. [51] as not noticeable (0-0.5), slightly noticeable (0.5-1.5), noticeable (1.5-3.0), well visible (3.0-6.0) and great (>6.0). Thus, \(\Delta E\) of the crust is categorized as well visible and, only in the case of THY doses 10 and 80 mg/100 g flour, is considered as great. However, evaluating this total color difference of crumb is more variable and is categorized as noticeable (40 THY and 10 LMG), great (20 LMG), and well visible for the rest. [PERSON] et al. [31] reported the discoloration of bread after the incorporation of thyme essential oil into a recipe as a result of the oxidation process that the essential oil undergoes, causing changes in food color.