## 1 Introduction
In this context, essential oils are one of the important replacements for their antioxidant, antibacterial, antifungal, antiviral, antiparasitic, and insecticidal properties [11]. Moreover, the aroma of essential oils can positively enhance the sensory properties and increase the attractiveness of baked goods. Essential oils are complex mixtures of the volatile compounds produced by plants. They can be synthesized in all plant organs, flower, bud, seed, leaf, stem, fruit, and root [12]. They are the secondary metabolites of aromatic plants [13]. Essential oils provide them protection against bacteria, viruses, fungi, and insects, and also enhance plant protection against herbivores [14]. Essential oil consists of approximately 20-60 different components. Usually, two or three components are dominant from 20-70%, while the remaining are present in trace amounts only [15]. The major components are mainly responsible for the biological function of the essential oil, but the remaining components also play a partial role [8]. Differences in the chemical composition and biological activity of essential oils depend on the climatic conditions of the growing area, the cultivation strategy, the plant variety, fertilization, and sufficient water intake during the growing season of the plant [16]. Variations in composition may also be due to the part of the plant from which they are obtained [15]. Spices and essential oils are used in food processing to enhance the flavor and extend the shelf life of foods [17]. The antimicrobials of plant origin led to an increase in overall quality and to the removal or reduction in pathogenic microorganisms. For example,eugenol in clove, cinnamaldehyde in cinnamon, carvacrol and thymol in oregano, sulfur compounds mainly diallyl trisulfide and diallyl disulfide in garlic, linalool in coriander, 1,8-cineol and camphor in rosmary, pulegone and limonene in parsley, citral in lemongrass, camphor in sage, and vanillin in vanilla have shown great antimicrobial effects [18]. However, the application of essential oils has some limitations despite its great potential. Essential oils can cause an allergic reaction and, from a certain amount, cause acute and chronic toxicity. Their use is also limited by the lack of scientific documentation for correct exposure dosages [14]. Another problem is their chemical variability. As the secondary metabolites of plants, essential oils are affected by external factors. This makes them extremely variable qualitatively and quantitatively over time. They have significant technological limitations for their application. The challenges are quality and standardization and strong sensory impact. Essential oils are volatile, unstable in air, and prone to oxidation. The extremely lipophilic nature of essential oils makes them difficult to use in polar solvents [19]. Thyme (_Thymus vulgaris_ L) is an aromatic, culinary, and medicinal herb of the _Lamiaceae_ family. It is native to the Mediterranean region [11]. The main components of thyme essential oil are thymol and carvacrol, in levels of up to 70%, and p-Cymene in levels of up to 40%. The ratio of the components varies according to the species, chemotype, or geographical origin. The remainder consists of linalool, limonene, geraniol, borneol, terpinene, and camphene [20]. The high antioxidant activity is mainly due to flavonoids, but phenolic compounds such as rosmarinic and caffeic acids, thymol, and carvacrol also exhibit antioxidant activity [21]. Lemongrass (_Cymbopgon winterianus_) Jowitt or _Cymbopgon nardus_ (L) W. [PERSON]) is a grass of Southeast Asia. It contains a significant amount of essential oil consisting mainly of citronellal, geraniol, and citral, which is characterized by a lemony aroma due to the citral compound. The essential oil exhibits medicinal, antifungal, antimicrobial, and antioxidant effects [22]. The main reasons for using essential oils in bakery are their antimicrobial and antioxidant effects.