## 1 Introduction
To increase shelf-life, essential oils can be added as a direct ingredient in the formulation of bakery products or can be added to the packaging material or the internal atmosphere of the package [10]. Bakery products with medium and high water activity are sensitive to microbiological spoilage. These products include filled bakery products, soft biscuits, and laminated bakery products. Almost all bacteria, yeasts, and molds can occur in bakery products with a water activity above 0.94. Breads, fruit pies, cakes, and pizzas fall into this category [23]. The antibacterial effects of essential oils are manifested by limiting bacterial growth or directly destroying bacterial cells [8]. In general, Gram-positive bacterial species are more sensitive to natural compounds than Gram-negative bacteria due to the absence of an outer membrane [24]. The antibacterial activity of different essential oils has been investigated against both Gram-positive bacteria (_Bacillus subtilis_, _Staphylococcus aureus_, and _Listeria monocytogenes_) and Gram-negative bacteria (_Escherichia coli_, _Salmonella typhimurium_, _Pseudomonas aeruginosa_, and _Campylobacter_ spp.) [8]. Both cinnamon and clove essential oils can inhibit both Gram-positive and Gram-negative bacteria [24]. Mustard, cinnamon, and clove essential oils slow down the spoilage process of baked goods. Lemon grass, cinnamon essential oil, clove essential oil, and thyme essential oil have fungicidal activity. Turmeric, lemongrass, and cloves when added to the recipe retarded the growth of mold in buttercakes [25]. Bakery products are prone to rancidity [25]. Antioxidant activity may also be associated with non-phenolic compounds such as limonene, linalool, and citral. Cinnamon and clove essential oils consist of various monoterenes and sesquiterpenes that show significant antioxidant activity; especially, cinnamaldehyde and eugenol are associated with antioxidant effects [8]. Rheological measurements can simulate and characterize the material properties during processing, thus allowing the quality control of products [26]. The rheological properties of dough are good indicators of behavior during kneading, fermentation, and baking [27]. Mixolab is a modern instrument for determining the quality control of cereals and flour. It is used to determine the thermomechanical properties of dough. The advantage of this method is that operating conditions such as kneader speed and temperature can be determined. This makes it possible to assess the effect of the addition of additives, kneading parameters, and the properties of the dough during heating [28]. For the analysis, 75 g of dough is used to determine the quality of protein and starch. The standard 'Chopin+' protocol analyzes dough kneading behavior, starch lubrication, amylase activity, and starch retrogradation in a single test [29]. Essential oils can influence the physicochemical and rheological properties of the dough. There are changes in the qualitative properties of baked goods such as volume, texture, and sensory characteristics [27]. The volume of the bread usually decreases, and the stiffness increases after the addition of essential oils. Essential oils are thought to bind to storage proteins or polysaccharides depending on their nature. This leads to a strengthening of the dough and a prolongation of the dough development time [30]. The use of thyme essential oil at concentrations equal to or greater than 0.15 mL/100 g of dough resulted in a significant reduction in bread volume [31]. The present study was aimed at the assessment of the effect of thyme and lemongrass essential oils on the bakery quality of common commercial wheat flour in several technological stages. Changes in behavior during kneading, i.e., in the viscoelastic properties of non-fermented dough were recorded on the Mixolab instrument. The course of fermentation was described by a row of the standard leavening microtests, and the final quality of bread in terms of laboratory baking trial was finalized by color evaluation.