Exploratory study on thyme leaf incorporation in durum wheat fresh pasta as a source of natural antioxidants: effects of cooking on quality attributes and rosmarinic acid stability

This study evaluated the effects of dried thyme leaf incorporation at two enrichment levels on the cooking behavior, antioxidant-related characteristics, and consumer acceptance of durum wheat pasta. Thyme addition influenced several cooking parameters, including prolonged cooking time, increased swelling, and higher cooking loss, while changes in pasta firmness were observed particularly at the higher enrichment level after cooking. From a compositional perspective, thyme supplementation enabled the introduction of rosmarinic acid (RA) into the pasta matrix, which was absent in the control samples. Thermal processing resulted in an overall reduction in total phenolic content; however, thyme-enriched pasta retained measurable levels of RA, with slight changes observed at the higher incorporation level. In addition, a tendency toward increased DPPH radical scavenging activity was observed after cooking. Sensory evaluation indicated that moderate thyme addition maintained overall consumer acceptability, whereas higher enrichment levels negatively affected flavor perception due to intensified herbal notes. Overall, the findings suggest that thyme may serve as a natural source of phenolic compounds in cereal-based pasta products, although the level of incorporation should be carefully balanced to preserve desirable quality attributes.