## 4 Conclusions  
In this study, a dietary fiber was obtained from Gavina(r) watermelon pomace. This allows to deal with overproduction in the agri-food sector and contributes to minimize waste production.  
The study of WDF_t0 aroma profile allowed to obtain important information regarding its chemical composition. The carotenoids content, especially lycopene and \(\beta\)-carotene, also present in the fresh fruit, has been confirmed by the detection of their volatile byproducts. These VOCs, together with C9 aldehydes, impart a characteristic and pleasant aroma to the fiber. Therefore, this raw material can find application in the food industry as an antioxidant-rich dietary fiber, as it preserves the bioactive molecules typical of watermelon. It can be used as an enriching ingredient in healthy food formulations, such as snacks or smoothies. The antioxidant power can also be exploited in the formulation of natural food supplements, thus finding use also in the pharmaceutical sector.  
The study of the aroma profile during storage showed significant changes in the chemical composition of the Gavina(r) WDF over time. VOCs relating to carotenoids are already absent after 30 days of storage. This may mean that their precursors have completely oxidized. It follows that our sample loses part of its bioactive compounds over time. The aroma profile notes during storage become increasingly grassy, green, and pungent. Consequently, this aged WDF can find application as a simple dietary fiber. It lacks a peculiar aroma and antioxidant carotenoids such as lycopene and \(\beta\)-carotene.  
In this study, storage was performed at room temperature and in the dark. It will be interesting to evaluate whether it will be possible to better preserve the bioactive molecules detected in the WDF_t0 by varying the storage conditions.  
**Supplementary Materials:** The following supporting information can be downloaded at: [[https://www.mdpi.com/article/10.3390/appliedchem3010006/s1](https://www.mdpi.com/article/10.3390/appliedchem3010006/s1)]([https://www.mdpi.com/article/10.3390/appliedchem3010006/s1](https://www.mdpi.com/article/10.3390/appliedchem3010006/s1)), Figure S1: Proposed biosynthetic pathway for watermelon VOCs: linolenic acid degradation; Figure S2: Proposed biosynthetic pathway for watermelon VOCs: linoleic acid degradation; Figure S3: Epoxidation of linalool to linalool oxide; Figure S4: Structure of some cyclic monoterpenes identified in the WDF samples; Figure S5: Chemical structure of cynene (left) and borneol (right); Figure S6: Lycopene, a carotenoid biosynthesized starting from geranyl pyrophosphate.  
**Author Contributions:** Conceptualization, L.M. and V.D.; methodology, L.M. and V.D.; software, V.D. and L.M.; validation, V.D., L.M. and L.T.; formal analysis, A.M., F.R. and L.T.; investigation, L.M. and V.D.; resources, A.M. and L.T.; data curation, L.M. and F.R.; writing--original draft preparation, L.T.; writing--review and editing, V.D., F.R. and A.M.; visualization, L.T., L.M. and V.D.; supervision, L.T., F.R. and A.M.; project administration, L.T. and F.R.; funding acquisition, L.T. and L.M. All authors have read and agreed to the published version of the manuscript.  
**Funding:** This research program has been funded by MIUR, the Italian Ministry of Education, University and Research. L.M. gratefully acknowledges financial support from POR FSE 2014-20 of Emilia-Romagna region (Italy) for doctoral fellowship.