The impact of seaweed life phase and postharvest storage duration on the chemical and rheological properties of hybrid carrageenans isolated from Portuguese Mastocarpus stellatus

► Seasonal variation in chemical composition and gel properties is found. ► No correlation between chemical and gel properties. ► Fructified gametophytes give best gelling hybrid carrageenans. ► Dried seaweeds stored during 39 months with preserved phycocolloid properties.