## 4 Conclusions  
This study indicated that the incorporation of post-distillation solid waste residues of the MAPs of oregano, rosmeary, lemon balm, and spearmint into wheat breads could affect some of their physicochemical properties and introduce the characteristic flavor notes of the respective plants into the bakery product. On the other hand, such fortification can enhance the content of antioxidants and result in sensorially acceptable products when the residues are used at relatively low levels of wheat flour substitution. Specifically, the addition of MAP wastes resulted in a darker crust and crumb color and a more greenish crumb color in breads fortified at both 1 and 2% levels. Instead, the incorporation of these by-products did not seem to affect the load specific volume, crust hardness, and crumb cohesiveness as well as crumb hardness after 4 days of storage at 25 \({}^{\circ}\)C, although the crumb chewiness increased, except in the case of rosmeary, for both fresh and stored fortified breads. Baking decreased the concentration of most of the phenolic compounds of the added residues, compared to the theoretically expected values; however, fortification of wheat bread with the plant residues seemed to be an effective means for enhancing the content of phenolic acids, terpenoid compounds and to a lesser extent flavonoids in breads, along with an increasing antioxidant capacity of the end-products. However, solid wastes had no considerable impact on mold growth on the crumb surfaces of the fortified breads during storage, most likely due to their low fortification levels or/and the fact that they led to higher crust and crumb moisture contents in the breads than those of control. The profile of volatile compounds, determined using gas chromatography, also showed an enrichment of the fortified breads with terpenoid compounds, which were detectable by trained sensory panelists, as well as providing to the baked products the characteristic aroma of the respective plant which was pleasant to the consumers (untrained panel) only at 1% fortification level. Overall, the inclusion of 1% of solid wastes in bread formulationswas sufficient to provide the aroma and taste of the respective MAPs, with the oregano waste bread obtaining the highest overall acceptability score, followed by bread with roscenary waste. This study confirms that post-distillation solid wastes of the studied MAPs are a sustainable alternative ingredient for the development of functional bakery products enriched in antioxidants that could provide beneficial effects on human health. Although the selected MAPs are native to the Mediterranean and Europe, they are common essential oil plants, while some of them have been naturalized and cultivated in several parts of the world. In conclusion, this study gives for the first time a detailed examination of both the phenolic and aromatic profile of a SWAP-enriched bread in combination with the quality and shelf-life attributes of the baked product. These results further demonstrate that the SWAP of the selected plants represents a promising source of sustainable phenolics with high antioxidant properties. Beyond that, the present study paves the way to the valorization of SWAP of similar chemical patterns' plants, commercialized for their essential oils all around the world. The following supporting information can be downloaded at: [[https://www.mdpi.com/article/10.3390/foods12214007/s1](https://www.mdpi.com/article/10.3390/foods12214007/s1)]([https://www.mdpi.com/article/10.3390/foods12214007/s1](https://www.mdpi.com/article/10.3390/foods12214007/s1)), Figure S1: Representative HPLC chromatograph showing the main phenolic components of the control (a) and fortified breads with 2% ORE (b), 2% ROS (c), 2% LEB (d) and 2% SPE (e) in the free extracts; inset graph shows the respective chromatogram at 320 nm of control bread in the bound extract (f). Sample symbols correspond to: ORE, oregano; ROS, roscenary; LEB, lemon balm; SPE, spearmint.