Use of the term 'umami' for the fifth basic taste and for describing the sensation of deliciousness is finding its way into Western cuisine. The unique molecular mechanism behind umami sensation is now partly understood as an allosteric action of glutamate and certain 5'-ribonucleotides on the umami receptors. Chefs have started using this understanding to create dishes with delicious taste by adding old and new ingredients that enhance umami. In this paper, we take as our starting point the traditional Japanese soup broth dashi as the 'mother' of umami and demonstrate how dashi can be prepared from local, Nordic seaweeds, in particular the large brown seaweed sugar kelp (Saccharina latissima) and the red seaweed dulse (Palmaria palmata), possibly combined with bacon, chicken meat or dried mushrooms to provide synergy in the umami taste. Optimal conditions are determined for dashi extraction from these seaweeds, and the corresponding glutamate, aspartate and alaninate contents are determined quantitatively and compared with Japanese dashi extracted from the brown seaweed konbu (Saccharina japonica). Dulse and dashi from dulse are proposed as promising novel ingredients in the New Nordic Cuisine to infuse a range of different dishes with umami taste, such as ice cream, fresh cheese and bread.Keywords: umami, seaweed, dashi, glutamate, kelp, dulse, New Nordic Cuisine Authors' summary for chefsHerein we review the concept of umami and deliciousness in a historical context and describe recent advances in the scientific understanding of the sensory perception of umami and the involved taste receptors. The primary stimulatory agent in umami is the chemical compound glutamate, which is found in large amounts in the Japanese seaweed konbu, which is used to prepare the soup broth dashi. We have explored the potential of local Nordic seaweeds, in particular sugar kelp and dulse, for dashi production and have discovered that dulse is high in free glutamate and hence a good candidate for umami flavouring. We describe methods by which to optimise the umami flavour using sous-vide techniques for extraction of the seaweeds, and we demonstrate how dulse dashi can be used in concrete recipes for ice cream, fresh cheese and sourdough bread.

Saccharina latissima is attractive for industrial cultivation for different usages, such as biofuels, feed supplements, and derivation of chemicals. A continuous supply of kelp sporelings throughout the year may ensure a yearround production of kelp juveniles on ropes. In this study, induction of sporangial areas (sorus portions) on the blade of S. latissima was performed throughout the year at three locations: Trondheim (Norway), Grenaa (Denmark), and Sylt island (Germany). The results indicate that a yearround sorus induction in S. latissima is possible and that this induction is controlled by applying short-day treatment of adult sporophytes throughout the year and by the removal of the basal blade meristem. The artificially induced and released zoospores formed viable sporelings at all seasons, but cultivation in the sea in Norway was successful only during autumn, winter, and spring, while the growth conditions were poor during the summer. The results are important for industrial scale-up and continuous production of kelp biomass.

Phosphorous removal 1,000,000 tons Assumes phosphorous content 0.2% of dry weight. Represents 61% of the phosphorous input as fertilizer. Carbon assimilation 135,000,000 tons Assumes carbon content 27% of dry weight. Equals 6% of the carbon added annually to oceans from greenhouse gas emissions. Bioenergy potential 1,250,000,000 MWH Assumes 50% carbohydrate content, converted to energy. Equals 1% of annual global energy use. Land sparing 1,000,000 km 2 Assumes 5 tons/ha average farm yield. Equals 6% of global cropland. Freshwater sparing 500 km 3 Assumes agricultural use averages 1 m 3 water/kg biomass. Equals 14% of annual global freshwater withdrawals.