Insights into the volatile profile of a red macroalga (Gracilaria vermiculophylla) for future food applications

Gracilaria vermiculophylla has the potential to be used as a food ingredient due to its nutritional and bioactive values, however, the aroma is considered a restrictive factor for its large acceptance by consumers. In-depth knowledge about its volatile profile is crucial for the definition of mitigation strategies to overcome this drawback and to improve its acceptability. This work aims to characterize the volatile profile of G. vermiculophylla using an advanced multidimensional chromatographic technique. For the first time, G. vermiculophylla volatile profile was unveiled and a total of 136 volatile compounds were determined and grouped by 10 chemical families, including aldehydes, ketones, alcohols, mono and sesquiterpenic compounds, norisoprenoids, esters, lactones, carboxylic acids, and halogenated compounds. From these, monoterpenic compounds were present in higher number (31 out 136) and aldehydes exhibited the largest GC areas (17–27 % of the total). A G. vermiculophylla aroma wheel was developed by combining data from the list of the detected volatile components with the respective aroma descriptors available in the literature. This strategy allowed to identify the volatile compounds whose aroma descriptors may potentially explain ca. 70 % of the aroma notes present in the algal aroma wheel. This included undesired fishy and sulfuric notes from dimethyltrisulfide and herbaceous notes from fatty acid derivatives, as aldehydes, and positive citric notes linked to monoterpenic compounds. However, G. vermiculophylla volatile compounds related to sweet, almond, beany, fresh, and minty notes, not yet considered in the algal aroma wheel, were also determined. This information may be further used to define mitigation strategies of non-valued algae aromas through volatiles' insights, contributing to the future acceptance of algae food products. [Display omitted] •Unveiling G. vermiculophylla volatile profile by HS-SPME/GC × GC–ToFMS•136 volatiles were determined across 10 chemical families.•Aroma descriptors of 38 volatiles are related to 22 out 32 algal wheel aroma notes.•Volatiles with undesired fishy, sulfuric, and herbaceous notes were determined.