**5. Conclusions**

Nowadays, olive mill waste products could be exploited as by-products to be used as fuels, fertilizers, or other intermediate products for the food, nutraceutical, cosmetic, and pharmaceutical industries. Olive leaf and olive oil mill wastewater have a good potential as sources of bioactive component and could be considered renewable source of high-added value. In this context, the aim of this study is to quantify the environmental impact of the extraction of phenolic compounds from olive oil mill waste. The phenolic extraction and encapsulation obtained from wastewater and olive leaves was characterized by low production yields, energy-intensive operations, and the partial use of chemical reagents. The addition of phenolic extract to food products (vegan mayonnaise, salad dressing, biscuits, and gluten-free breadsticks) leads to enhancing the environmental impact of production process but also implies an improvement of technological and nutritional performance. The potential shelf life of enriched food preparations induces an increase up to two times with respect to control due to the presence of TPC added. This is a crucial aspect to consider in the normalization of environmental impact based on technological

and nutritional parameters. This work should be the basis for future research focused on the environmental impact comparison between the use of phenolic extract deriving from olive oil mill waste and the packaging operations to improve shelf life performance in food chain. Moreover, this research can open further studies to identify the best combo choice between biocompounds and packaging design to reduce food waste, reduce packaging, and promote the circular economy business model.

**Supplementary Materials:** The following are available online at https://www.mdpi.com/article/10 .3390/foods10050980/s1, Figure S1: System boundary, Table S1: Environmental impact comparison of mayonnaise and enriched mayonnaise considering commercial unit, potential shelf-life and TPC parameters, Table S2: Environmental impact comparison of salad dressing and enriched salad dressing considering commercial unit and TPC parameters, Table S3: Environmental impact comparison of biscuits and enriched biscuits considering commercial unit, technological and nutritional parameters, Table S4: Environmental impact comparison of gluten free breadsticks and enriched GFB considering commercial unit, technological and nutritional parameters.

**Author Contributions:** Author Contributions: Conceptualization, A.P. (Alessia Pampuri), A.C., A.T., R.B., R.G., and V.G.; methodology, A.P. (Alessia Pampuri), A.C., A.T. and R.B.; formal analysis, A.P. (Alessia Pampuri), A.C., and V.G.; investigation, C.A, C.D.D.M., A.P. (Amalia Piscopo), G.D., P.C., and M.P.; resources, C.A, C.D.D.M., A.P. (Amalia Piscopo), G.D., P.C., and M.P.; data curation, A.P. (Alessia Pampuri), A.C., and V.G.; writing—original draft preparation, A.P. (Alessia Pampuri), A.C. and V.G.; writing—review and editing: A.T., R.B., C.A., C.D.D.M., A.P. (Amalia Piscopo), G.D., P.C., M.P., R.G. and E.C.; supervision, R.G., and V.G.; funding acquisition, E.C. All authors have read and agreed to the published version of the manuscript.

**Funding:** This research was funded by AGER 2 Project, grant no. 2016-0105.

**Institutional Review Board Statement:** Not applicable.

**Informed Consent Statement:** Not applicable.

**Data Availability Statement:** Data is contained within the article or supplementary material.

**Acknowledgments:** The authors wish to thank Francesco Caponio for the supervision of the whole research project.

**Conflicts of Interest:** The authors declare no conflict of interest. The funder had no role in the design of the study; in the collection, analyses, or interpretation of data; in the writing of the manuscript, or in the decision to publish the results.

#### **References**


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