Environmental conditions influence on the physicochemical properties of wild and cultivated Palmaria palmata in the Canadian Atlantic shore

Seaweeds are a promising biomass resource that contain proteins with high potential for sustainable exploration. Palmaria palmata, one of the main red seaweeds of the Canadian coast, has a high protein content and much interest as an ingredient. Understanding the associations between environmental conditions and P. palmata color and chemical composition is of paramount importance to predict optimum harvesting conditions and thus increase its value. This study investigated the influence of environmental conditions on the composition and color of wild and cultivated P. palmata. Important changes in these parameters were found for P. palmata harvested in the subarctic Canadian transition zone, depending on the harvesting site/month. A marked increase in carbohydrates and decrease in ashes content (up to 2-fold) were observed from June to October, while photosynthetically active radiation (PAR) values have decreased. These associations suggest that wild P. palmata is shade acclimated to the Gulf of Saint Lawrence region. Maximum protein content was found for samples in June and was especially higher for samples from Grande-Rivière. Samples were intensely colored in June, possibly related to the higher protein content found in this month. Although several intricate factors seem to influence color development in this species, data from this study assist harvesting sites and period to maximise dark red color and avoid pigmentation degradation and paleness. In sum, these results may help indicate the best site/period to take commercial advantage of this species and orient future research on the multifactored relationships between environmental factors and macroalgae chemical composition and color.

Mots clés

• Chemical compounds
• Environmental parameters
• Red algae
• Canadian boreal-subarctic transition zone