The generally recognized as safe (GRAS) microalgae Haematococcus pluvialis (wet) as a multifunctional additive for coloring and improving the organoleptic and functional properties of foods

This work proposes the application of astaxanthin-rich H. pluvialis wet paste (HPW) as a partial substitute for wheat flour in the preparation of filloas, a dish that combines the basic ingredients of industrial bakery. The nutritional and color profile of HPW-enriched samples was evaluated by comparative analysis with a mixture of synthetic food dyes. The highest content of carotenoids (798 ± 12 µg g−1) and fatty acids (76 ± 2mgg−1) was obtained for a filloa fortified with H. pluvialis in contrast to a non-significant dye response. Subsequently, the color stability of the fortified filloa was evaluated over time (3, 6 and 9 days), as well as its physicochemical properties and microbiological profile. As a result, HPW provided filloas with a longer shelf life, brightness (*L), and texture, in comparison with a mixture of synthetic dyes. In addition, an inhibitory effect of HPW towards mesophilic aerobic microorganisms in the food was obtained.This research was funded by project ED431 2020/06 (Galician Competitive Research Groups Xunta de Galicia). All these pro- grammes are co-funded by FEDER (EU). The authors are also grateful to the Foundation for Science and Technology (FCT; Portugal) for financial support through national funds FCT/ MCTES (PIDDAC) to CIMO (UIDB/00690/2020 and UIDP/ 00690/2020) and SusTEC (LA/P/0007/2021). Castillo A. acknowl- edges the support of the European Grouping of Territorial Cooperation Galicia-Norte Portugal (GNP, EGTC) under the IACOBUS Program and the MCI of Spain for his contract part of the grant DIN2021-011976 funded by the MCIN/AEI/ 10.13039/501100011033. L. Barros and S. Heleno acknowledge the national funding by FCT, P. I., through the institutional scientific employment program-contract for their contracts, and Filipa A. Fernandes for the PhD grant (SFRH/BD/145467/ 2019).