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. 2023 Oct 9;12(19):3707.
doi: 10.3390/foods12193707.

On the Valorization of Arbutus unedo L. Pomace: Polyphenol Extraction and Development of Novel Functional Cookies

Hugo Duarte  1 , Ceferino Carrera  2 , María José Aliaño-González  1   2 , Rocío Gutiérrez-Escobar  3 , María Jesús Jiménez-Hierro  3 , Miguel Palma  2 , Ludovina Galego  1   4 , Anabela Romano  1 , Bruno Medronho  1   5
Affiliations

On the Valorization of Arbutus unedo L. Pomace: Polyphenol Extraction and Development of Novel Functional Cookies

Hugo Duarte et al. Foods. .

Abstract

The fruits of Arbutus unedo L. have a crimson colour and are enriched with remarkable concentrations of bioactive compounds such as anthocyanins and polyphenols. These fruits are commonly used in the production of a Portuguese Protected Geographical Indication distillate called "Aguardente de Medronho". During this process, a solid pomace is generated and presently discarded without valuable applications. In this work, two strategies have been developed for the valorisation of A. unedo pomace. The first approach considers the extraction of polyphenols from this by-product through the optimization of an ultrasound-assisted method using a Box-Behnken design coupled with response surface methodology. The results indicate that the temperature and the percentage of methanol, along with their interaction, significantly influence the total concentration of polyphenols and the antioxidant activity of the extracts obtained. The optimal conditions identified consider the extraction of 0.5 g of sample with 20 mL of a solvent containing 74% MeOH (aq), at a pH of 4.8, maintained at 70 °C for 15 min. On the other hand, the second valorisation strategy considered the use of A. unedo pomace in the development of functional cookies. The incorporation of 15-20% pomace in the cookie formulation was well-received by consumers. This incorporation results in an intake of ca. 6.55 mg of polyphenols per gram of cookie consumed, accompanied by an antioxidant activity of 4.54 mg Trolox equivalents per gram of cookie consumed. Overall, these results encourage the employment of A. unedo pomace either as a reliable source of extracts enriched in polyphenols or as a nutraceutical active ingredient in functional cookies, thereby positively impacting human health.

Keywords: Arbutus unedo L.; antioxidant activity; distillate pomace; functional cookies; ultrasound-assisted extraction.

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Conflict of interest statement

The authors declare no conflict of interest.

Figures

Figure 1
Figure 1
Pareto Chart of BBD-RSM analysis of (A) total polyphenols extracted from A. unedo pomace and (B) antioxidant activity of the extracts. The vertical line marks the 95% confidence level.
Figure 2
Figure 2
Effect of extraction time on the (A) total polyphenol concentration (mg/g dw) and (B) antioxidant activity (mg Trolox eq./g dw) of A. unedo pomace (n = 3). Different letters indicate significant differences at 95% confidence level.
Figure 3
Figure 3
Summary of the panelists’ evaluation of the cookies developed with the seedless A. unedo pomace powder (i.e., 0%, 15%, 20%, 40%, and 60%).
Figure 4
Figure 4
(A) Total polyphenol concentration (mg/d dw) and (B) antioxidant activity (mg TE/g dw) of the extracts obtained from cookies with and without seeds analyzed under optimal extraction conditions. Different letters indicate significant differences at 95% confidence level.
See this image and copyright information in PMC

References

    1. Molina M., Pardo-de-Santayana M., Tardío J. Natural production and cultivation of mediterranean wild edibles. In: Sánchez-Mata M.d.C., Tardío J., editors. Mediterranean Wild Edible Plants: Ethnobotany and Food Composition Tables. Springer; New York, NY, USA: 2016. pp. 81–107.
    1. Arnan X., Quevedo L., Rodrigo A. Forest Fire Occurrence Increases the Distribution of a Scarce Forest Type in the Mediterranean Basin. Acta Oecol.-Int. J. Ecol. 2013;46:39–47. doi: 10.1016/j.actao.2012.10.005. - DOI
    1. Pallauf K., Rivas-Gonzalo J.C., del Castillo M.D., Cano M.P., de Pascual-Teresa S. Characterization of the Antioxidant Composition of Strawberry Tree (Arbutus unedo L.) Fruits. J. Food Compos. Anal. 2008;21:273–281. doi: 10.1016/j.jfca.2007.11.006. - DOI
    1. Oliveira I., Baptista P., Malheiro R., Casal S., Bento A., Pereira J.A. Influence of Strawberry Tree (Arbutus unedo L.) Fruit Ripening Stage on Chemical Composition and Antioxidant Activity. Food Res. Int. 2011;44:1401–1407. doi: 10.1016/j.foodres.2011.02.009. - DOI
    1. Ruiz-Rodríguez B.-M., Morales P., Fernández-Ruiz V., Sánchez-Mata M.-C., Cámara M., Díez-Marqués C., Pardo-de-Santayana M., Molina M., Tardío J. Valorization of Wild Strawberry-Tree Fruits (Arbutus unedo L.) through Nutritional Assessment and Natural Production Data. Food Res. Int. 2011;44:1244–1253. doi: 10.1016/j.foodres.2010.11.015. - DOI

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